HomeMy WebLinkAbout2019-11-21 Executed_PGE_Implementation_Work_Order
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CITY OF SAN LUIS OBISPO WATER TREATMENT PLANT SUSTAINABLE SERVICES TURNKEY
IMPLEMENTATION PROJECT
WORK ORDER
This WORK ORDER (“Work Order”), effective as of the date of the latest signature executing this
agreement (“Work Order Effective Date”) is made and entered into by and between City of San Luis Obispo
(“Customer”) and Pacific Gas and Electric Company (“PG&E”). This Work Order is subject to the terms and
conditions of the PG&E Master Services Agreement, Contract # 21007 between Customer and PG&E dated
09/18/2018 (“Services Agreement”). Customer and PG&E are referred to collectively as the “Parties.”
In accordance with the provisions of the Services Agreement, the Customer wishes to engage PG&E to
provide the Implementation Work on the following Project:
PROJECT NAME: San Luis Obispo SST Water Treatment Plant Upgrades
CONTRACT No.: 21007
WORK ORDER AMOUNT $13,999,644
1. SCOPE OF WORK
1.1 PG&E will procure equipment for, construct, implement and deliver to Customer those
measures described in the Scope of Work (“SOW”) at Customer’s Water Treatment Plant, located at 1900
Stenner Creek Road, San Luis Obispo, CA 93405 facility described in the SOW (each facility a “Site” and
collectively the “Sites”). The SOW is attached hereto as Exhibit A and incorporated by reference herein.
The services to be performed under this Work Order shall be referred to hereinafter as the
“Implementation Work”.
PG&E shall have no obligations to perform any Implementation Work under this Work Order
unless and until PG&E and Customer have signed this Work Order. The issuance of this Work Order does
not commit PG&E to perform any future work for Customer.
1.2 Subcontractors. PG&E reserves the right to engage third party subcontractors
(“Subcontractors”) to perform some or a portion of the Implementation Work. PG&E agrees that, as
between PG&E and Customer, PG&E shall be solely responsible for the Subcontractors performance of
the Implementation Work under this Work Order. In addition, unless otherwise set forth in this Work
Order, the fees and costs billed to Customer shall be inclusive of any, and all, fees and compensation due
to any Subcontractors. PG&E shall be responsible for the payment of any compensation, monies, wages
or other payment due or allegedly due Subcontractors, including prevailing wages. For purposes of this
Agreement, PG&E and its Subcontractors shall be collectively referred to as “PG&E”.
1.3 Term of Work Order. This Work Order shall commence upon the Work Order Effective
Date and shall continue until all the Implementation Work is complete; unless sooner terminated or
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extended as permitted under the Services Agreement (the “Work Order Term”). PG&E shall complete the
Implementation Work in accordance with the milestone dates described in the project schedule attached
hereto as Exhibit B and incorporated by reference herein.
2. PERFORMANCE OF THE IMPLEMENTATION WORK
2.1 Project Construction
2.1.1 PG&E’s Responsibilities.
2.1.1.1. Upon execution of this Work Order by Customer and approval of project
financing, PG&E shall commence and complete construction and implementation of the Project in
accordance with the Services Agreement, this Work Order, the attached SOW and any applicable Work
Order modifications. PG&E will provide all professional and other services, labor, materials, equipment,
tools, transportation and other services necessary for the proper performance and completion of the
Implementation Work per the City stamped plans and specifications approved for construction, and in
accordance with Customer applicable codes, regulations, and the 2018 Standard Specifications and
Engineering Standards. PG&E will be responsible for the means, methods, techniques, sequences and
procedures to implement the Project, and shall oversee Project construction including construction
management, and inspection testing per the plans and specifications approved for construction.
2.1.1.2. PG&E will use commercially reasonable efforts to minimize disruption to
Customer’s use and operations at the Site. PG&E will provide at least ten (10) calendar days written notice
to Customer of any planned power or other utilities outages that will be necessary for the Implementation
Work. Customer will cooperate with PG&E in scheduling such outages, and Customer agrees to provide
its reasonable approval of any scheduled outage.
2.1.1.3. Customer has first rights to all equipment being removed during demolition.
PG&E will coordinate with Customer to identify all items to be turned over to Customer prior to start of
demolition. At least five (5) days prior to commencement of demolition, Customer shall provide to PG&E
a written list of all equipment to be returned to Customer prior to completion of demolition. PG&E will
provide legal offsite disposal for all items not returned to the Customer. Customer is responsible for all
labor, equipment, rigging and transportation necessary to remove demolished items from the jobsite and
transport them to their final location.
2.1.2 Customer's Responsibilities.
2.1.2.1. Customer will take reasonable measures to provide PG&E, its personnel and
Subcontractors with site access, suitable office space and other reasonable accommodations and facilities
necessary to permit PG&E personnel and its Subcontractors to perform the Implementation Work on this
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Project. While working on the Site, if requested by Customer, the PG&E Project team personnel will be in
an area adjacent to Customer's subject matter experts and technical personnel, and all necessary security
badges and clearance will be provided for access to this area, all in accordance with Customer’s vendor
policies. Additionally, upon request Customer will provide to PG&E and its Subcontractors relevant site
information or documents necessary to perform the Implementation Work, including but not limited to a
copy of this Work Order, all Work Order modifications, the Services Agreement, a copy of relevant
drawings, specifications, operation and maintenance manuals for equipment at the Site, and other
pertinent documents.
2.1.2.2. Customer will arrange for a temporary staging area for the storage and assembly
of equipment for completion of the Implementation Work, if needed.
2.1.2.3. Customer will coordinate the Implementation Work to be performed by PG&E
with the Customer’s operations and other activities and with any other construction project that is
ongoing at or around the Site.
2.2 Training and Commissioning Services. PG&E shall provide training to Customer on
equipment that PG&E installs in accordance with the terms of this Work Order, and as described in the
SOW. PG&E shall perform start up, testing, and commissioning services in accordance with the equipment
manufacturers’ startup and commissioning recommendations and the Project Schedule. Customer
reserves the right to contract a third-party inspection company to spot-check the work performed by
PG&E under this agreement at any time during the construction phase.
2.3 Certificate of Substantial Completion. Promptly upon substantial completion of each
Project measure, PG&E will submit a Certificate of Substantial Completion to Customer for such measure.
Upon receipt of such certificate, Customer may inspect the Implementation Work and meet with PG&E’s
Project Manager to determine if the Project measure has achieved substantial completion. Customer
shall, within ten (10) business days of receipt of the Certificate of Substantial Completion, inform PG&E if
Customer agrees that the Project measure has achieved substantial completion. If Customer disagrees
that the Project measure has achieved substantial completion, Customer will specify in detail and in
writing the deficiencies requiring correction in order to achieve substantial completion. When substantial
completion has been achieved, Customer will file a Notice of Completion (NOC) with the County
Recorder’s Office, and return the NOC with a Certificate of Substantial Completion to PG&E stating that:
(i) the Project measure has achieved substantial completion and the date on which it did so, and (ii) that
on and after that date Customer will assume responsibility for the Project measure’s operation,
maintenance and repair, for damage to or destruction of the Project measure, and for the Project
measure’s security and insurance coverage. Title to the Project measure materials and equipment
installed pursuant to this Work Order shall pass to Customer on the date of substantial completion
together with equipment warranties.
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2.4 Close-Out Documentation. Within thirty (30) days after each Certificate of Substantial
Completion has been executed by Customer and received by PG&E, PG&E shall provide Customer with
(a) any applicable governmental approvals, permits, and sign-offs, (b) all equipment specifications and
ratings, (c) any applicable test data and reports, (d) CAD drawings and PDFs of final as-built and shop
drawings, (e) operating instructions, operations and maintenance manuals and schedules, recommended
spare parts lists, and all other written information relating to the Project measure, and (f) equipment
warranties.
2.5 Final Completion. Promptly after PG&E reasonably believes that Final Completion has
occurred, PG&E shall issue to Customer a Notice of Final Completion (defined below in Section 2.5.1).
Thereafter, Customer shall, within fourteen (14) business days, deliver its acknowledgment that Final
Completion has been achieved. The date of Final Completion shall be the date of Customer’s written
acceptance of PG&E’s Notice of Final Completion. Customer’s failure to respond within the thirty (30) day
notice period shall be deemed acceptance that Final Completion has occurred.
2.5.1 For purposes of this Work Order, the term “Final Completion” means the date
when all of the following have been accomplished: (a) each Project measure has achieved Substantial
Completion, (b) all “punch list” items have been completed, (c) all Close-out documentation has been
delivered to Customer, (d) PG&E has delivered to Customer: (i) a release of all lien rights, (ii) certification
that all claims for payment for labor and equipment for which PG&E is responsible have been paid or
satisfied, (iii) copies of waivers/releases of lien rights by Subcontractors that have furnished more than
twenty-five thousand dollars ($25,000) of goods, services or both for the Project, (iv) notice of all
outstanding claims of PG&E, any Subcontractor or equipment or materials supplier or distributor that may
affect Customer, PG&E or the Project, (v) a letter of indemnification regarding claims not addressed by
waivers/releases, and (vi) removal of all of PG&E and Subcontractors’ personnel, supplies, equipment,
waste materials, rubbish, and temporary facilities from the Site.
2.6 PG&E shall not be liable for any claims, liabilities, or losses arising out of, resulting from,
or in any way connected with, Customer’s: (a) neglect, misuse or abuse of the equipment; (b) use of
unauthorized parts, or removal of any parts; (c) repair, modification or alteration of equipment by anyone
other than authorized representatives as described in the warranties covering the equipment;
(d) relocation of the equipment.
3. MODIFICATIONS
If a modification to this Work Order is necessary, the Parties agree to follow the modification
process set forth in Section 4.2. of the Services Agreement.
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4. PAYMENT
4.1 PG&E will submit invoices, certified payrolls (redacted and unredacted), and daily
inspection reports on a monthly basis to Customer based upon the agreed-upon Bid Schedule, which is
attached hereto as Exhibit C and incorporated by reference herein. Prior to the first application for
payment a baseline schedule, and schedule of values detailing labor, equipment, and materials shall be
approved by the City. A 5% retention will be applied to the monthly progress payment in accordance with
Public Contract Code Section 22300 and Customer’s 2018 Engineering Standards and Specifications. Final
release of the payment retention shall be conducted in accordance with the City requirements as specified
in the 2018 Engineering Standards and Specifications. Proof of insurance, performance bonds, and
payment bonds shall be executed and submitted to Customer within 10 working days after Notice of
Award (NOA). A Notice to Proceed (NTP) will be issued after all bonds and insurance documents have been
approved by Customer.
4.2 Each PG&E invoice will reference this Work Order and be submitted to Customer’s billing
address. Customer shall instruct its financial institution or Project financier to render all payments to
PG&E within thirty (30) days from the invoice date and when Customer has received a complete
application for payment per Section 4.1. Each payment made by Customer or its third-party designee
must reference this Work Order and invoice number and be mailed to:
PACIFIC GAS AND ELECTRIC COMPANY
Attn: Sales and Service Manager, Business Development
P.O. Box 770000, Mail code: N10D
San Francisco, CA 94177
5. ORDER OF PRECEDENCE
In the event of a conflict between the provisions of the Work Order, any modification to the Work
Order, and the Services Agreement, the following order of precedence shall apply (in descending order):
(a) the modification to this Work Order, (b) the Work Order, and (c) the Services Agreement.
6. NOTIFICATIONS AND INTERFACE
Both Parties shall contact and/or deliver written notices (email is allowed) to the business contacts below
in the normal course of business, and in the event of any problems which may significantly affect the
performance of the Implementation Work under this Work Order.
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BUSINESS CONTACTS
CUSTOMER REPRESENTATIVE PG&E REPRESENTATIVE
Name Name Brent Patera
Title Title Business Development Manager
Address Address 245 Market Street, Mail Code N10D
San Francisco, CA 94105
Telephone Telephone 415-973-5335
Email Email Brent.Patera@PGE.com
7. AUTHORITY
Each Party represents and warrants that the individual signing below, as well as any Work Order
Modifications and approvals hereunder, has and shall have all requisite power and legal authority to bind
the Party on whose behalf he/she is signing to that Party’s obligations hereunder.
IN WITNESS THEREOF, the parties agree to be bound by this Work Order as of the date first set forth
above.
CITY OF SAN LUIS OBISPO PACIFIC GAS AND ELECTRIC COMPANY
Signature: Signature:
Print Name: Print
Name:
Title: Title:
Date: Date:
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EXHIBIT A
SCOPE OF WORK
Scope of Work Overview
PG&E will implement energy conservation measures (“ECMs”) at the Customer’s Water Treatment Plant
(“WTP”). The ECMs are described generally below, and more specifically in the Investment Grade Audit
Report, dated 10/18/19 (“IGA Report”). The IGA Report is attached hereto as Attachment 1 and is
incorporated herein. The Scope of Work (“SOW”) to be included in the Work order as outlined in the IGA
includes:
ECM # ECM Name
2 Ozone System Upgrade
4 Transfer Pump Station Upgrades
9 Plant Service Water System Upgrades
11 SCADA /Controls Upgrades
ECM # 2 –Ozone System Upgrade
The focus of this measure is the removal and replacement of the existing ozone water treatment system
with a new system that offers improved reliability, functionality and uses less energy to operate when
compared to the existing system.
The SOW includes the removal and proper disposal of the existing ozone system in its entirety with a new
turnkey system which will include all components necessary for a complete functioning system. The new
ozone generators will be a modular design system by Primozone, a Pureflow Ozone Division. The new
generators will be fed by new LOx storage and delivery systems. As this is a replacement of a critical
system in an operating plant, careful consideration was given to the planned approach. It is understood
that the WTP must always remain in operation during construction. The construction shall be
accomplished in four phases: Phase 1 Demolition; Phase 2 Construction, Phase 3 Demolition; and Phase 4
Construction. Ozone generators #1 and #2 and destruct Unit #2 shall remain fully operable during Phase
1 until the new system is online and accepted by the owner.
For the construction phase, a written schedule outlining the proposed phasing and sequence of the work
will be developed by PG&E and the Customer to ensure that the WTP remains in operation during the
duration of the construction.
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ECM # 4 – Transfer Pump Station Upgrades
This measure includes the addition of Variable Frequency Drives (“VFDs”) to each of the four existing
transfer pumps. The VFDs will improve overall system efficiency and controllability by providing Customer
with the ability to slowly ramp up each pump when the transfer pumps are brought online. Consequently,
Customer will more easily be able to eliminate pressure spikes, and will have the ability to continually
modulate the pump speed to meet varied demands of the high-pressure system.
This ECM will include the following SOW:
• Install a wall-mounted Allen Bradley VFDs for each of the four existing transfer pumps and
integrate the VFDs into the Supervisory Control and Data Acquisition (“SCADA”) system. Each VFD
will be configured with a bypass, disconnect switch, line reactor and communication interface
compatible with Allen Bradley CompactLogix controllers.
• Modify the existing hardwired controls for the transfer pumps and their discharge valves to
function with the new VFDs.
• Integrate the existing tank level sensor at the Bishop Storage tank to monitor the high-pressure
system.
• Add sequence of operation in the SCADA system to allow for automatic operation of the Transfer
pumps to directly serve the high-pressure system when Reservoir-2 is out-of-service or
disconnected from the system.
• Add programming to the Throttle Position Sensor (“TPS”) control system with logic to optimize
the operation of the pumps when serving Reservoir-2 based on Clearwell Levels, Reservoir-2 levels
and Time-of-Use (“TOU”) electric rates.
ECM # 9 – Plant Service Water System Upgrades
This ECM will include the following SOW:
This measure includes the replacement of the existing booster pump system (“BPS”) with a new packaged
system that is sized for the flow rates that will occur after PG&E completes ECM 2 by replacing the ozone
system. The new BPS will utilize variable speed pumps to efficiently maintain the required system
discharge pressure. The BPS system will include a pressurized diaphragm tank that discharges water to
the plant service water system when the pumps shut off during low-demand conditions. The proposed
BPS is manufactured by Grundfos. The factory-assembled system includes three variable speed,
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multistage vertical inline pumps with integrated motor/VFD rated for 80 GPM each, suction and discharge
piping, and a control panel.
The SOW includes:
• Removal and disposal of the existing BPS and control panel.
• Furnishing, installing, start-up and commissioning the new BPS and diaphragm tank.
• Provision of temporary BPS for the PSWS during demolition of the existing system and
installation of the new system.
ECM # 11 – SCADA/Controls Upgrades
The objective of this measure is to improve the existing WTP SCADA system by upgrading the existing
controllers to a platform that is compatible with the recently-installed system on the water distribution
system.
This measure includes the replacement of the existing Bristol Babcock controllers with CompactLogix
and/or ControlLogix Programmable Logic Controllers (“PLCs”) by Allen-Bradley. Compact Logix and
Control Logix represent small and large PLCs from the same family of controllers. Compact Logix and
Control Logix PLCs are fully compatible with each other and use the same programming software. The
system replacements/upgrades are described below.
• At the Ozone building CSP-1 and CSP-7:
o PG&E will remove the existing controllers and infrastructure. One new integrated Ozone
controller will be provided and installed in conjunction with the Ozone system upgrade
described in ECM 2. This new controller will be provided with the following:
▪ Provide a new cabinet and custom back panel
▪ The new integrated Ozone controller will be an Allen Bradley PLC
▪ Add a new power supply and uninterruptable power supply
▪ Provide new Ethernet switch
▪ Provide new terminal blocks, Relays, Fuses as required
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• At the Ozone contact basin CSP-2:
o PG&E will remove this existing controller and associated wiring as it will no longer be
needed for the new Ozone system upgrade installed as part of ECM 2
• At the Filter Building CSP–3 and CSP-4:
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
• At the Chemical Building CSP-5:
o Replace with new PLC in the existing cabinet and location
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
• At the Plant Water Service Pump Station CSP-6:
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
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• At the TPS CSP-8:
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, relays, and fuses as required
• Reprogramming Services. PG&E will reprogram the upgraded PLCs listed above with existing
sequences, alarms and trending
• Portable computer tablets. PG&E will provide two (2) portable computer tablets (Apple iPad or
equal) with Graphic interface software to optimize operator interface
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EXHIBIT B
ESTIMATED PROJECT SCHEDULE
Below is the estimated project schedule. PG&E will submit a detailed schedule following the kick-off
meeting.
Duration Assumed Start Assumed Finish
Preconstruction 241 days 12/02/19 11/02/20
Receive NTP 1 day 12/02/19 12/02/19
Bond and Insurance 5 days 12/01/19 12/16/19
Write Subcontracts 5 days 12/17/19 12/23/19
Cushman Precon 190 days 12/24/19 09/14/20
Design Drawings 4 months 12/24/19 04/13/20
Submittal Review Process Ozone
Equipment
8 weeks 12/24/19 02/17/20
Submittal Review Process Concrete
Rebar Pip
8 weeks 12/24/19 02/17/20
Submittal Review Process Electrical and
Pumps
8 weeks 04/14/20 06/08/20
Release electrical 1 day 06/09/20 06/09/20
Release ozone equipment 1 day 02/18/20 02/18/20
Ozone equipment lead time 14 weeks 02/18/20 05/25/20
Procure miscellaneous material 4 weeks 02/19/20 03/17/20
Procure electrical and pumps 14 weeks 06/09/20 09/14/20
SCADA Precon 225 days 12/24/19 11/02/20
Engineering and Submittals 180 days 12/24/19 08/31/20
Materials Procurement 45 days 09/01/20 11/02/20
Hazmat layout and testing 6 days 04/14/20 04/21/20
Permits 5 days 04/14/20 04/20/20
Construction 305 days 03/18/20 05/18/21
Ozone 275 days 03/18/20 04/06/21
Mobilize CCC 5 days Wed 3/18/20 Tue 3/24/20
LOX Excavate for Tank pad and LOX
receiving 4 weeks Wed 3/25/20 Tue 4/21/20
LOX Form pour Strip LOX tank pad
and LOX receiving 6 weeks Wed 4/22/20 Tue 6/2/20
LOX excavate Lay Backfill LOX Yard
Pipe 4 weeks Wed 6/3/20 Tue 6/30/20
LOX set and connect LOX tank and
Evaporators 1 weeks. Wed 7/1/20 Tue 7/7/20
Phase 1 Ozone Demo 7 weeks Wed 4/22/20 Tue 6/9/20
Phase 1 Concrete 3 weeks Wed 6/10/20 Tue 6/30/20
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Phase 1 Equipment 4 weeks Wed 7/1/20 Tue 7/28/20
Phase 1 Mechanical 6 weeks Wed 7/29/20 Tue 9/8/20
Phase 1 Electrical 8 weeks Wed 8/26/20 Tue 10/20/20
Ozone Phase 1 Training 5 days Wed 10/21/20 Tue 10/27/20
Phase 1 Startup and Test 5 weeks Wed 10/21/20 Tue 11/24/20
Phase 2 Demo 4 weeks Wed 11/25/20 Tue 12/22/20
Phase 2 Concrete/Tile 2 weeks Wed 12/23/20 Tue 1/5/21
Phase 2 Mechanical 4 weeks Wed 1/6/21 Tue 2/2/21
Phase 2 Electrical 6 weeks Wed 1/20/21 Tue 3/2/21
Ozone Phase 2 Training 5 days Wed 3/3/21 Tue 3/9/21
Phase 2 Startup and Test 5 weeks Wed 3/3/21 Tue 4/6/21
Plant Service Water Upgrade 41 days Tue 9/15/20 Tue 11/10/20
Mobilize CCC 1 day Tue 9/15/20 Tue 9/15/20
Demo and set up bypass 2 weeks Wed 9/16/20 Tue 9/29/20
Install new pumps and mechanical 3 weeks Wed 9/30/20 Tue 10/20/20
Install new Electrical 1 week Wed 10/21/20 Tue 10/27/20
Training 5 days Wed 10/28/20 Tue 11/3/20
Startup and Test 1 week Wed 11/4/20 Tue 11/10/20
Transfer Pump Station Upgrades 26 days Wed 11/11/20 Wed 12/16/20
Mobilize CCC 1 day Wed 11/11/20 Wed 11/11/20
Install TPS VFD's 3 weeks Thu 11/12/20 Wed 12/2/20
Training 5 days Thu 12/3/20 Wed 12/9/20
Startup and Test 1 week Thu 12/10/20 Wed 12/16/20
SCADA Upgrades 218 days Mon 7/6/20 Wed 5/5/21
Mobilize TESCO 2 days Mon 7/6/20 Tue 7/7/20
Site Installation Work 150 days Wed 7/8/20 Tue 2/2/21
Training 5 days Wed 2/3/21 Tue 2/9/21
System Implementation and startup 61 days Wed 2/10/21 Wed 5/5/21
Closeout 30 days Wed 4/7/21 Tue 5/18/21
TOTALS 382 days 12/2/19 05/18/21
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EXHIBIT C
BID SCHEDULE
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ATTACHMENT 1
INVESTMENT GRADE AUDIT REPORT
Investment Grade Audit Report for:
WATER ENERGY EFFICIENCY PROJECT
CITY OF SAN LUIS OBISPO
UTILITIES DEPARTMENT
October 17, 2019
Prepared by:
Southland Energy
a Division of Southland Industries
12131 Western Ave
Garden Grove, CA 92841
1.800.613.6240
P +714.657.1500
southlandindenergy.com
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 2
Table of Contents
1 EXECUTIVE SUMMARY ...................................................................................................................... 4
1.1 Key Objectives and Goals ......................................................................................................... 4
1.2 Summary of Findings and Benefits ........................................................................................... 5
1.3 Financial Summary .................................................................................................................... 7
2 APPROACH TO INVESTMENT GRADE AUDIT ................................................................................. 8
2.1 Methodology .............................................................................................................................. 8
2.2 Facility Data Analysis ................................................................................................................ 8
2.3 Achieving Climate Action and Zero Net Energy Goals .............................................................. 8
2.4 Acknowledgements ................................................................................................................. 10
3 UTILITY DATA ANALYSIS ................................................................................................................ 11
4 ENERGY CONSERVATION MEASURES ......................................................................................... 17
4.1 Introduction .............................................................................................................................. 17
4.2 Phase 1 (Efficiency) ECMs ...................................................................................................... 17
4.3 Phase 2 (Resiliency) ECMs ..................................................................................................... 32
4.4 Other ECMs ............................................................................................................................. 32
5 APPENDICES .................................................................................................................................... 38
List of Figures
Figure 1.1: GHG Forecast & Target for Government Operations (from Climate Action Plan, Aug. 2012) ... 6
Figure 1.2: Zero Net Energy - SST Project’s Impact on Water Utility’s Energy ............................................ 6
Figure 2.1: Phase 1 (Efficiency) GHG Forecast &Target for Government Operations (from Climate Action
Plan, Aug. 2012) ........................................................................................................................................... 9
Figure 2.2: Zero Net Energy – Phase 1 (Efficiency) Impact on Water Utility’s Energy ............................... 10
Figure 3.1: Annual Electric Use for Water Utility Facilities .......................................................................... 12
Figure 3.2: WTP Top Five Energy Consuming Systems (Initial version from PEA) ................................... 14
Figure 3.3 WTP Top Five Energy Consuming Systems (IGA Version) ...................................................... 14
Figure 4.4: Ozone Generator and Power Supply Unit ................................................................................ 17
Figure 4.5: TPS Controller (CSP) ............................................................................................................... 25
Figure 4.8: Plant Service Water System Booster Pumps ........................................................................... 27
Figure 4.9 Measured PSWS and CW Flow Rates ...................................................................................... 28
Figure 4.10: Reservoir-1 PV Site Plan ........................................................................................................ 35
List of Tables
Table 1.1: Energy Conservation Measures and Key Benefits ...................................................................... 5
Table 1.2: ECM Financial Summary ............................................................................................................. 7
Table 3.1: Annual Electric Consumption and Costs ................................................................................... 11
Table 3.2: WTP - System and Equipment List and Energy Use ................................................................. 15
Table 4.1: Ozone System Major Equipment List......................................................................................... 23
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 3
List of Acronyms
Acronym Definition Acronym Definition
AFY Acre-feet Per Year PV Photovoltaic
ATS Automatic Transfer Switch Res-1 Reservoir No. 1
BPS Booster pump system Res-2 Reservoir No. 2
CAP Climate Action Plan SA Salinas Reservoir
CMC California Men’s Colony SST Sustainable Solutions Turnkey
CW Cooling water TOU Time-of-Use
DPC Distributed Process Controller TPS Transfer Pump Station
ECM Energy Conservation Measure VFD Variable Frequency Drive
ESCO Energy Services Company WDS Water Distribution System
FA Feasibility Assessment WR Whale Rock Reservoir
FERC Federal Energy Regulatory Commission WSP Welded Steel Pipe
FPA Federal Power Act WTP Water Treatment Plant
GHG Greenhouse gas ZNE Zero Net Energy
GOx Gaseous oxygen
GPM Gallons per minute
HPS High pressure sodium
HVAC Heating, Ventilation, and Air Conditioning
IGA Investment Grade Audit
kW Kilowatt
kWh Kilowatt Hour
LOx Liquid oxygen
M&V Measurement and Verification
MCC Motor Control Center
MG Million gallons
mg/l Milligrams per liter
MGD Million gallons per day
MH Metal halide
MSL Mean Sea Level
MW Megawatt
NWP Nacimiento Water Project
NREL National Renewable Energy Laboratory
O&M Operation and Maintenance
PG&E Pacific Gas and Electric
PLC Programmable Logic Controller
PRV Pressure reducing valve
PSWS Plant Service Water System
PSI Pounds per Square Inch
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 4
1 EXECUTIVE SUMMARY
In response to the global climate crisis, Pacific Gas & Electric (PG&E) is committed to supporting the City of
San Luis Obispo (City) in meeting its social, fiscal and environmental obligations to its citizens. This Investment
Grade Audit (IGA) provides practical solutions that ensure that the City remains a dynamic and high-quality
place to live and work. PG&E is proud to partner with the City as it goes forward with its strategy to Act, Adapt,
and Thrive by creating community assets that provide economic, social, and environmental value to the
community, which includes the following key goals:
• Environmental
o Develop and implement a holistic strategy to maximize sustainable resource recovery
o Prioritize responsible use of water resources
o Incorporate sustainability practices in planning, design, construction, and operation
o Maintain compliance and minimize impacts to operations and the community during
construction
o Sustain reliable compliance during post-construction operation and maintenance
• Social
o Create and sustain diverse partnerships that add value to the community
o Provide opportunities to engage and educate the community
o Be a good neighbor
o Engender the trust of project stakeholders
o Support the development and empowerment of City employees
• Economic
o Optimize capital investment and life cycle cost
o Maximize value for ratepayers’ investment
o Incorporate flexibility and scalability to adapt to future conditions
o Simplify process flow and make treatment more robust
The project proposed lays the foundation for achieving carbon neutrality by 2035, through the audit and
planning of measures that enhance the community’s resilience to the impacts of climate change. The work
will be coordinated with key City objectives and goals to ensure successful implementation.
As funding for the Water Energy Efficiency Project is limited, implementation is proposed by the City to
proceed in two phases. Phase 1 (Efficiency) includes Energy Conservation Measures for critical components
of the City’s Water Treatment Plant (Upgrades to the Ozone System, Transfer Pump Station, Plant Service
Water System, and the SCADA System). Four other Energy Conservation Measures that provide the City
resiliency through renewable energy would take place in a subsequent phase of the project. These are
identified as Phase 2 (Resiliency) in this IGA (Hydro Power Generation, WTP Backup Power, Photovoltaic
Energy Generation (Solar), and Lighting Improvements).
1.1 Key Objectives and Goals
To develop a comprehensive plan to achieve the aforementioned goals, the City engaged PG&E to develop
this IGA report for the Water Treatment Plant (WTP). The key objectives and goals for this IGA were jointly
developed by the City, PG&E and Southland and are outlined below.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 5
1. Align with the City’s vision to create community assets that provide economic, social, and
environmental value for the community
2. Identify opportunities that reduce energy consumption, improve infrastructure, and enhance
operational resiliency
3. Leverage renewable energy generation by maximizing the use of on-site solar generation and by
capitalizing on hydro generation from the Nacimiento Reservoir
4. Reduce operations and maintenance costs while improving operational efficiency
5. Identify project funding sources that maximize economic benefits to the City
1.2 Summary of Findings and Benefits
The Phase 1 Energy Conservation Measures (ECM) and the corresponding key benefits and financial
summary, are outlined in Tables 1.1 and 1.2. The Phase 1 ECMs provide progress towards the City’s efforts
to achieve its Climate Action Major City Goal of reducing greenhouse gas (GHG) emissions to the 1990
level by 2020, and being a Zero Net Energy (ZNE) utility consumer. Implementation of the Phase 1 ECMs
will reduce GHG emissions by City operations by as much as 118 MTCO2e (Metric Tons CO2 equivalent).
This is 15 percent of the reduction target of 770 MTCO2e identified for Government Operations in the 2012
Climate Action Plan (CAP) (see Figure 1.1 below), 0.30 percent of the Community Wide GHG reduction
target (15 percent of the 2005 baseline of 264,230 MTCO2e), and 29 percent of the water treatment plant’s
GHG emissions from electricity use. Additionally, the reduced energy use created by the proposed
efficiency ECMs will reduce the City’s water utility’s current annual electricity consumption by 19 percent.
Table 1.1: Energy Conservation Measures and Key Benefits
Benefit Impact
Legend:
Significant Moderate Minor None
KEY BENEFITS
Social Environment Economic
ECM ECM Description Facility Water Quality Human Health Supply & Resiliency Operations Renewable Energy Zero Net Energy Energy Savings Infra- structure Cost Reduction Phase 1 (Efficiency)
2 Ozone System Upgrade WTP
4 Transfer Pump Station
Upgrades WTP
9 Plant Service Water System
Upgrades WTP
11 SCADA/
Controls Upgrades WTP
Phase 2 (Resiliency)
1 Hydro Power Generation WTP
3 WTP Backup Power WTP
5 Photovoltaic Energy Generation
(Solar) WTP
7 Lighting Improvements WTP
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 6
Figure 1.1: GHG Forecast & Target for Government Operations (from Climate Action Plan, Aug. 2012)
Figure 1.2: Zero Net Energy - SST Project’s Impact on Water Utility’s Energy
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 7
1.3 Financial Summary
By implementing the Phase 1 (Efficiency) measures shown in Table 1-2, the City will realize annual energy
cost savings of $115,830 and net annual operational and maintenance savings of $11,230. In addition, the
City will avoid future capital costs planned for the WTP .
Estimated savings for Phase 2 (Resiliency) will be completed in the future when preliminary design work is
available to inform these estimates.
Table 1.2: ECM Financial Summary
ECM
ID ECM Description Facility
ID
Annual
Savings
(kWh)
ECM Cost Annual Utility
Cost Savings (1)
Additional
Annual O&M
Costs (LOx)
Annual
O&M
Cost
Reduction
Total
Annual Cost
Reduction
2 Ozone System
Upgrade WTP 541,009 $12,133,235 $104,506 $38,770 $50,000 $115,736
4 Transfer Pump
Station Upgrades WTP - $456,060 $ - $ - $ - $ -
9 Plant Service Water
System Upgrades WTP 70,224 $366,795 $11,324 $ - $ - $11,324
11 SCADA/
Controls Upgrades WTP - $1,043,554 $ - $ - $ - $ -
611,233 $13,999,644 $115,830 $38,770 $50,000 $127,060
Note: (1) Utility cost savings are based on the PG&E E-19 Tariff effective 7/1/2019.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 8
2 APPROACH TO INVESTMENT GRADE AUDIT
2.1 Methodology
The approach taken in the development of this IGA is a collaborative one in which PG&E/Southland
gathered City stakeholders (WTP management and operations staff), City and County sustainability
experts, as well as subject matter experts to explore each proposed ECMs. During this process these
stakeholders were interviewed and asked for input on desired outcomes that would streamline processes
at the WTP, improve efficiency, solve current systematic problems, as well as align with the City’s
sustainability goals. This information was used throughout the process and revisited during the multiple
workshop help to guide and align outcome to the goals. This team approach allows the City to have a voice
in the process and ultimate outcome of the proposed measures.
2.2 Facility Data Analysis
To properly evaluate the potential of each ECM the PG&E/Southland team performed a thorough
investigation process of the existing facility. During this process an examination of the design documents
and system operational data was performed, comprehensive analysis of utility data and bills, performed on-
site audits, analyzed data for key systems, and utilized existing data to gain a thorough understanding of
the energy consumption and load profiles. This information was used to further evaluate the ECMs identified
in the Preliminary Energy Assessment.
The following City facilities were analyzed in this IGA:
• Water Treatment Plant
• Ferrini Pump Station
• Whale Rock Pump Stations A and B
• Reservoir No. 1
2.3 Achieving Climate Action and Zero Net Energy Goals
The City identified Climate Action as one of its four Major City Goals in its 2019-2021 Financial Plan. Major
City Goals are defined as the most important, highest priority goals for the City to accomplish over the next
two years. Key elements of this goal include assessing the requirements to achieve a “net-zero carbon City”
target, and implementing cost-effective measures. This PG&E Sustainable Solutions Turnkey (SST) project
contributes to achieving this Major City Goal by:
• Performing energy assessments/audits at the City’s water utility facilities.
• Implementing energy and cost saving measures identified in the energy assessments that are
aligned with the goals and strategies in the CAP including:
o Government Operations Strategy GO-1 – City Energy Conservation
o Government Operations Strategy GO-2 – City Renewable Energy
o Government Operations Strategy GO-5 – Water and Wastewater Infrastructure
• Implementing renewable energy systems that reduce the City’s utility costs and consumption of
fossil fuel-based energy.
• Reducing greenhouse gas (GHG) emissions from City operations toward the goals of being 15
percent below the City’s GHG baseline by 2020 and being a “net-zero carbon City.”
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 9
The recommended measures in Phase 1 (Efficiency) and Phase 2 (Resiliency) would provide significant
progress towards the City’s efforts to achieve its Climate Action goal of reducing GHG emissions to the
1990 level by 2020 and being a Zero Net Energy (ZNE) utility consumer.
Implementation of the identified Phase 1 (Efficiency) measures will reduce GHG emissions from City
operations by as much as 118 MTCO2e (Metric Tons CO2 equivalent). This is 15 percent of the reduction
target of 770 MTCO2e identified for Government Operations in the CAP, 0.30 percent of the Community
Wide GHG reduction target (15 percent of the 2005 baseline of 264,230 MTCO2e), and 29% of the water
treatment plant’s GHG emissions from electricity use. Additionally, the reduced energy use created by the
proposed efficiency ECMs will reduce the City’s water utility’s current annual electricity consumption by
nearly 19 percent. This is illustrated in Figure 2.2 below.
The estimated reduction in GHG emissions for Phase 2 (Resiliency) will be completed in the future when
preliminary design work is available to inform these estimates.
Figure 2.1: Phase 1 (Efficiency) GHG Forecast &Target for Government Operations (from Climate Action
Plan, Aug. 2012)
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 10
Figure 2.2: Zero Net Energy – Phase 1 (Efficiency) Impact on Water Utility’s Energy
2.4 Acknowledgements
The PG&E/Southland team would like to express our gratitude to the City for committing its valuable team
members to the IGA process, and for the opportunity to present our findings to the City Council. A special
thank you goes out to Aaron Floyd, Mychal Boerman, Jason Meeks, Miguel Barcenas, Marcus Henderson,
Jennifer Metz, and Chris Read of the City of San Luis Obispo, and John Griesser of the County of San Luis
Obispo Energy Watch for their significant contributions to this IGA.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 11
3 UTILITY DATA ANALYSIS
The utility analysis is a key, fundamental element of the IGA that is used to gain a deeper understanding of
utility consumption and costs for each of the City’s facilities. The results of the analysis provide the
foundation for all subsequent steps in the IGA, including comparison and benchmarking of facilities,
allocation of energy and cost to systems within individual facilities, and savings calculations.
The City of San Luis Obispo receives electric utility service (21 meters) for its water facilities from PG&E.
PG&E provided 36 months of electrical use and cost data (Sept ember 2014 – September 2017) and 12
months of 15-minute interval data to the Sustainable Solutions Turnkey (SST) team for the Utilities
Department’s water utility facilities and the Whale Rock raw water system facilities1. A summary of the
annual electric consumption and costs for each facility in the potable water system is captured in Table 3.1
and Figure 3.1 below. Total annual energy use is over 3.1 million kWh at a total cost of over $628,000. The
City’s WTP and the two Whale Rock pump stations account for 96 percent of the total annual energy use
and 94 percent of the cost. This insight helps to focus the SST team’s efforts during the IGA to areas where
the greatest impact on energy use, demand, and related costs can be made.
Table 3.1: Annual Electric Consumption and Costs
1 Whale Rock facilities are jointly owned by the City of San Luis Obispo, the California Men's Colony, and the California
Polytechnic State University at San Luis Obispo. These three agencies form the Whale Rock Commission which is
responsible for operational policy and administration of the reservoir. Day-to-day operation is provided by the City.
Facility Name
PG&E Meter
#
Total
Annual Use
(kWh)
Annual
Electricity
Cost ($)
Max
Billing
Demand
(kW)
Total
Annual
Cost ($)
% of Total
Electric
Use
% of
Total
Cost
Water Treatment Plant 1010078556 2,100,124 345,695 499 346,304 66.1%55.1%
Whale Rock Pump Station #2 1010002034 487,690 126,038 390 126,183 15.4%20.1%
Whale Rock Pump Station #1 1010027122 467,245 118,397 406 118,533 14.7%18.9%
Bressi Pump Station 1006909621 31,679 6,992 48 7,001 1.0%1.1%
Reservoir No.2 1010116728 23,782 5,616 4 5,623 0.7%0.9%
Ferrini Pump Station 1009500372 21,325 11,962 79 11,968 0.7%1.9%
McCollum Pump Station 1006472096 14,408 3,268 37 3,272 0.5%0.5%
Reservoir No.1 1009921396 10,834 2,604 0 2,608 0.3%0.4%
Whale Rock Shop 1008718720 10,585 2,628 9 2,632 0.3%0.4%
Rosemont Pump Station 1005529721 1,558 439 11 440 0.0%0.1%
Whale Rock Streetlights 1006875451 1,382 442 0 442 0.0%0.1%
Corp Yard Well 1009608623 1,287 534 0 534 0.0%0.1%
Bishop Tank 1009657691 1,060 331 0 331 0.0%0.1%
Bishop Pump Station 1006909452 1,037 443 47 443 0.0%0.1%
Alrita Pump Station 1006708574 734 377 1 377 0.0%0.1%
Pacific Beach Well 1004497758 415 328 8 328 0.0%0.1%
Madonna PRV 1008780550 410 204 0 204 0.0%0.0%
Edna Saddle 1010262147 344 315 0 315 0.0%0.1%
Terrace Hill PRV 1009488291 249 171 0 171 0.0%0.0%
Fire Station #4 Well 1009568491 77 256 0 256 0.0%0.0%
Whale Rock SCADA Repeater 1008718721 75 139 3 139 0.0%0.0%
Totals =>3,176,300 627,178 628,104
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 12
Figure 3.1: Annual Electric Use for Water Utility Facilities
3.1 Water Treatment Plant Baseline Energy Analysis and Allocation
During the previous Preliminary Energy Assessment (PEA) we performed an initial allocation (breakdown)
of the WTP’s annual energy use to the equipment and systems in the WTP to gain an understanding of
where the energy is used. Based on that analysis, the top five energy consuming systems in the WTP were
identified (accounting for more than 96 percent of the annual energy) and that initial breakdown of the
WTP’s energy by system is shown in Figure 3.2. To characterize the baseline energy use within the WTP
in the IGA in more detail, we took power measurements and installed temporary instrumentation (data
loggers) to record energy use and hours of operation for key WTP equipment and systems. The data
loggers recorded data for one-year starting in May 2018 which provides a clear picture of the equipment’s
annual energy use and operating hours. The following list shows the equipment in the measurement
program. Additional information about the field measurements and data logger implementation are
contained in the “Field Measurement Record” and “Data Logger Field Installation Plan & Record”
documents located in Appendix C.
• Power supply units (PSU) for the ozone generators PSU-1, PSU-2, and PSU-3
• Air compressors for ozone air preparation AC-1, AC-2, and AC-3
• Ozone destruction units ODU-1 and ODU-2
• Transfer pumps TP-1, TP-2, TP-3, and TP-4
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 13
• Plant service water pumps PSWP-1, PSWP-2, and PSWP-3
The measured data was used to determine the annual energy use for the equipment above and used those
results to update the energy allocation analysis from the PEA. The IGA version of the chart for the energy
breakdown for the top five energy consuming systems is in Figure 3.3.
The detailed list of significant systems and equipment evaluated in the allocation analysis, and the
estimated energy use for each is shown in Table 3.2. Note that the air compressors shown within the
disinfection process in Table 3.2 are the prime components in the air-preparation system for the ozone
generators and are integral to the ozone system. The process of determining the breakdown of the annual
electrical energy use for the WTP included:
• Confirm the primary energy consuming systems and equipment and their ratings.
• Measure energy use and operating hours for key equipment included in IGA ECMs.
• Determine the annual operating hours for equipment without measurements.
• Estimate the average power draw for the equipment without measurements over the course of a
year of operation.
• Calculate the annual energy use for the equipment.
• Calculate the total annual energy use for all the equipment in the allocation analysis and
compare the total to the annual use in the utility bills.
The inventory of the primary energy consuming systems and equipment and their ratings were confirmed
through site visits, review of WTP drawings and documentation, and discussions with WTP personnel. The
equipment inventory is entered in the analysis spreadsheet including the associated WTP system/process,
equipment type, and electrical rating for each piece of equipment (typically motor horsepower). This
information is the foundation for the analysis and summarizing the results.
The next step involved estimating the average annual power draw in kilowatts (kW) for the equipment
without energy measurements. The estimated power draw (or load) was determined by using the
equipment’s electrical rating as the maximum possible power draw and then applying a load factor (0 to
100 percent) to the rating to arrive at the value for the analysis. The load factors used in the WTP analysis
were influenced by one or more factors including method of motor control (constant speed or variable
speed), typical operating speed if variable, observed operating conditions (including actual operating power
draw from a submeter or equipment controller, flowrate, pressure, etc.), input from WTP operating staf f,
and professional experience.
The last element of determining the energy use for the equipment without energy measurements was to
determine the annual operating hours and apply that to the average power draw. The process of
determining the operating hours was similar to determining power draw and primarily utilized observed
operating conditions, input from WTP operating staff, and professional experience. It is important to note
that many processes/systems in the WTP have redundant equipment that do not operate simultaneously
with the lead equipment. In most of these cases, operation of the lead and backup e quipment will be
switched to distribute the annual run time across the equipment. To simplify the calculations for redundant
equipment, all of the annual operating hours are attributed to the lead machine(s) and the backup will have
zero hours.
The equipment inventory with the associated electrical ratings, load factors, power draw, operating hours
and calculated energy use is included in Appendix C.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 14
Figure 3.2: WTP Top Five Energy Consuming Systems (Initial version from PEA)
Figure 3.3 WTP Top Five Energy Consuming Systems (IGA Version)
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 15
Table 3.2: WTP - System and Equipment List and Energy Use
Major Process/Top Energy Use Systems
Electric
Energy Use
(%)
Electric Energy
Use (kWh/year)
Electric Energy
Cost ($/year)
Energy
Measured or
Estimated
Disinfection
Blower - Ozone Destruction Unit #1 1.72% 36,129 $5,890 Measured
Blower - Ozone Destruction Unit #2 0.38% 7,931 $1,293 Measured
Compressor - Air Compressor-1 6.79% 142,532 $23,237 Measured
Compressor - Air Compressor-2 9.90% 207,881 $33,891 Measured
Compressor - Air Compressor-3 6.77% 142,239 $23,189 Measured
Other kW Load - Ozone Gen-1/PSU 6.99% 146,898 $23,949 Measured
Other kW Load - Ozone Gen-2/PSU 5.45% 114,504 $18,668 Measured
Other kW Load - Ozone Gen-3/PSU 5.31% 111,529 $18,183 Measured
Distribution Pumping
Pump - Transfer Pump 1 7.94% 166,652 $27,169 Measured
Pump - Transfer Pump 2 7.63% 160,271 $26,129 Measured
Pump - Transfer Pump 3 8.29% 174,019 $28,370 Measured
Pump - Transfer Pump 4 8.09% 169,962 $27,709 Measured
Flocculation / Sedimentation
Mixer - Coagulation Basin Mixer CMX-1 1.55% 32,448 $5,290 Estimated
Mixer - Coagulation Basin Mixer CMX-2 0.00% 0 $0 Estimated
Mixer - Flash Mixer #1 1.55% 32,448 $5,290 Estimated
Mixer - Flash Mixer #2 0.00% 0 $0 Estimated
Mixer - Injection Basin Mixer IMX-1 1.55% 32,448 $5,290 Estimated
Mixer - Injection Basin Mixer IMX-2 0.00% 0 $0 Estimated
Mixer - Maturation Basin Mixer MMX-1 1.16% 24,336 $3,967 Estimated
Mixer - Maturation Basin Mixer MMX-2 0.00% 0 $0 Estimated
Pump - Sand Pump SP-1A 2.50% 52,416 $8,545 Estimated
Pump - Sand Pump SP-1B 2.50% 52,416 $8,545 Estimated
Pump - Sand Pump SP-1C 0.00% 0 $0 Estimated
Pump - Sand Pump SP-2A 0.00% 0 $0 Estimated
Pump - Sand Pump SP-2B 0.00% 0 $0 Estimated
Pump - Sand Pump SP-2C 0.00% 0 $0 Estimated
Internal Plant Pumping
Pump - Plant Service Water Skid Pump #1 2.14% 44,972 $7,332 Measured
Pump - Plant Service Water Skid Pump #2 2.13% 44,813 $7,306 Measured
Pump - Plant Service Water Skid Pump #3 0.33% 6,916 $1,128 Measured
Lighting
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 16
Major Process/Top Energy Use Systems
Electric
Energy Use
(%)
Electric Energy
Use (kWh/year)
Electric Energy
Cost ($/year)
Energy
Measured or
Estimated
Other kW Load - All Outdoor Lighting 2.75% 57,816 $9,426 Estimated
Other kW Load - Control/Ozone Bldg Lighting 1.35% 28,382 $4,627 Estimated
Other kW Load - Lab/Filter Bldg Lighting 0.58% 12,096 $1,972 Estimated
Non Process HVAC
Other kW Load - Control/Ozone Bldg HVAC 1.06% 22,192 $3,618 Estimated
Other kW Load - Lab/Filter Bldg HVAC 0.80% 16,819 $2,742 Estimated
Sludge Handling
Pump - Wash Water Reclaim Pump PMP-3 2.32% 48,672 $7,935 Estimated
Pump - Wash Water Reclaim Pump PMP-4 0.00% 0 $0 Estimated
Estimated Annual Electric Use & Cost 2,089,737 $340,690
Actual Annual Electric Use & Cost 2,100,124 $330,008
Difference Between Billed and Identified 10,387 $10,682
Percent of Site Electrical Energy Identified 99.51%
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 17
4 ENERGY CONSERVATION MEASURES
4.1 Introduction
The Investment Grade Audit evaluated 12 Energy Conservation Measures (ECMs) identified in the
preliminary energy audit. The evaluation process was carried out through a combination of meetings and
interviews with on-site staff, field visits of facilities, analysis of utility and benchmark data, and energy and
economic analysis of potential ECM opportunities. During this process critical information was evaluated to
guide the team’s decision process toward which measures to include or not include in the recommend ECM
list. The sections below describe Phase 1 (Efficiency) ECMs recommended for priority implementation,
Phase 2 ECMs that will be considered as future resiliency measures, and those ECMs that are
recommended for further evaluation/implementation. Each ECM includes a discussion of the existing
conditions, identified solutions, and estimated benefits for each ECM.
4.2 Phase 1 (Efficiency) ECMs
ECMs included in Phase 1 (Efficiency) are those measures recommended for priority implementation.
4.2.1 ECM-2 Water Treatment Plant (WTP) Ozone System Upgrade
Existing Conditions
The WTP treats raw water from the Whale Rock Reservoir, the Salinas Reservoir (Santa Margarita Lake),
and the NWP. The existing treatment process includes pre -ozonation, coagulation, ballasted flocculation,
and filtration, followed by disinfection with hyp ochlorite for inactivation of 3 log for Giardia and 4 log for
virus. For 2016 through August 2017, the average daily production was 4.53 MGD. The original hydraulic
design capacity of the plant is 16 MGD. However, the plant is currently limited to a maximum of 12.0 MGD
by the ballasted flocculation basins. The permitted capacity of the plant is 10.5 MGD.
Previous pilot testing and operational experience has shown tha t ozonation is a very effective disinfectant
and oxidant for the City. The ozonation process has allowed the City to meet primary disinfection and
minimize formation of regulated disinfection byproducts, while providing taste and odor control, color
reduction, and enhanced filtration performance. Other disinfectants such as chlorine, chloramines, and
chlorine dioxide were considered in the past; however, ozonation was deemed the best alternative. UV
disinfection has been considered as a viable alternative because of its effectiveness for inactivation of
Giardia and Cryptosporidium, but it does not provide the other process and water quality benefits that
ozonation provides.
The existing ozonation system, which consists of air -preparation,
generation, addition, and destruction, was installed in 1994. The air-
preparation system consists of air-fed compressors, aftercoolers, and
dryers. The ozonation, air-preparation and ozone destruction
equipment is approximately 25 years old, which is causing increased
need for investment in service and repair. This was reflected in the
City’s 2019-2021 Financial Plan where at least $149,000 per year was
budgeted for maintenance of the ozone and air-preparation systems in
fiscal years 2019-20 through 2021-22. The most challenging and costly
maintenance is for the ozone generators since the supplier (Emery -
Trailigaz) is no longer in the municipal drinking water market, the ozone
generators are obsolete products, replacement parts are scarce, and the pool of qualified and experienced
service providers is very limited.
Figure 4.1: Ozone Generator and
Power Supply Unit
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 18
Variability of Ozone Demand
In 1994, ozone was incorporated as the primary disinfectant at the WTP to minimize the formation of
disinfection byproducts during the water treatment process. At the time, the WTP treated water from two
sources: Whale Rock Reservoir and the Salinas Reservoir. In 2007, prior to the introduction of water from
the NWP, the City performed an evaluation of ozone demand as a function of various blend ratios of the
two water sources.
With three, blend-able surface water sources, the ozone demand can be quite varied.
To identify the range of ozone demand across a variety of flows and source water blend s, an ozone pilot
study was performed prior to selection of the preferred treatment equipment. The pilot study is described
in further detail below and the final report is provided as Appendix D.
Baseline Energy Analysis
As part of the IGA, temporary instrumentation was installed to measure and record the energy use and
hours of operation for the primary energy consuming equipment in the ozone system including three air-
preparation air compressors (AC-1, AC-2 and AC-3), three ozone generators/power supply units
(OG-1/PSU-1, OG-2/PSU-2 and OG-3/PSU-3) and two ozone destruction units (ODU-1 and ODU-2). The
measurements were recorded for one year starting in May 2018. The annual energy use for the ozone
system equipment determined from the measurements is summarized in the following table.
In addition, the results of the plant service water system (PSWS) flow and energy analysis, show that 86,989
kWh per year of the PSWS pump energy use is attributable to the ozone system due to the service water
that is used in the cooling water system. The pump energy for the cooling water system combined with the
ozone system equipment accounts for nearly half of the WTP’s annual energy cons umption of roughly
2,100,000 kWh. A chart of the daily energy use for each set of equipment, and the energy calculations are
located in Appendix C.
Ozone Pilot Study
The primary objective of the pilot study was to assist in proper equipment sizing by identifying maximum
ozone demand for various blend ratios of the three primary water sources supplying the WTP. WTP staff
also desired to investigate the possibility of increasing the ozonation system capacity to match the
maximum capacity of the ballasted flocculation system, or 12 MGD per train.
The project team developed an Ozone Piloting Protocol defining the testing requirements necessary to
provide sufficient information for the design and selection of the new equipment.
The Protocol included the following requirements:
1. Design of the pilot facilities, including contact chamber(s), residence chamber, and ozone destruct
system to simulate the existing WTP facilities with similar baffling and ozone diffusion. The facilities
were required to also allow operation with residence time that would simulate 12 MGD through a
single ozone contact basin.
2. Provide five mg/L ozone dose into the maximum flow. Ozone dose shall be variable to allow testing
at various flowrates and ozone doses.
Equipment
Baseline
Energy Use
(kWh/year)
Ozone Generators/PSUs 372,930
Ozone Air Compressors 492,653
Ozone Destruct Units 44,060
Total 909,643
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 19
3. Water supply to the pilot system was provided from the ozone contact chamber feed channel via a
variable speed pump to provide proper flow to the test equipment. Filter backwash water was
returned to the contact basin during the testing to simulate worst-case conditions.
4. Pilot feedwater blends established by the City via adjusting the feed to the WTP.
5. Perform online ozone analysis after the contact chamber required to allow automated data
collection during the pilot test.
6. Install and perform pilot testing at the varying blend rates. 15 blends were identified for testing in
the pilot study. These are summarized below, expressed in the number of pumps running at booster
pump stations for Salinas and Whale Rock Reservoir, and in delivery flowrate (MGD) for
Nacimiento Water Project:
a. Single-source test for each of the water sources:
i. Whale Rock Reservoir (WR)
ii. Salinas Reservoir (Sal)
iii. Nacimiento Water Project (NWP)
b. Binary blends for all three combinations:
i. WR/Sal
1. 1 WR/1 Sal
2. 2 WR/1 Sal
3. 1 WR/2 Sal
ii. WR/NWP
1. 2 WR/ 2.0 MGD NWP
2. 1 WR/3.5 MGD NWP
3. 1 WR/5.3 MGD NWP
iii. Sal/NWP
1. 2 Sal/2.0 MGD NWP
2. 1 Sal/3.5 MGD NWP
3. 1 Sal/5.3 MGD NWP
c. Trinary blends at prescribed increments (WR/SAL/NWPi)
i. 1 WR/1 Sal/2.0 MGD NWP
ii. 1 WR/ 1Sal/5.3 MGD NWP
iii. 1 WR/2 Sal/3.5 MGD NWP
7. Each blend rate was maintained for a duration sufficient for determining the ozone residual.
8. Determine the optimal ozonation rates to achieve 0.5 log inactivation of Giardia for each of the
blending rates, and verify sufficient data is available to predict ozone concentrations.
9. Provide pilot report, with recommendations for ozone system configuration and operation.
The pilot testing was performed on-site at the WTP from September 17, 2018 through September 21, 2018.
The testing was conducted utilizing the two (2) individual ozone contactors and a mass transfer skid to
simulate the pre-ozonation process of the raw surface water ahead of the ozone contact chamber.
All objectives were met through the ozone pilot study. Over 750 dissolved ozone residual data points were
recorded throughout the study with hundreds of other associated set points recorded for each piece of
equipment. Residence times between 11.32 minutes and 6.50 minutes were recorded and applied doses
ranged from 3 mg / L to 9 mg / L. 12 MGD simulations were completed on four different blends while
successfully achieving a CT value of 0.12 mg-min / L on each of the said blends.
All three water resources were studied on both an individual and blended basis. The ozone production
required to achieve CT requirements for any blend of water as treated during the pilot study was determined
to be as follows:
• 606 lb/day (8 MGD)
• 910 lb/day (12 MGD)
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 20
Preliminary Equipment Basis of Design
Based on the results of the pilot study and prior to design, the project team prepared a preliminary
evaluation of candidate equipment capable of meeting the requirements identified in the pilot. T he purpose
of the evaluation was to focus the equipment selection and design on equipment that best meets the needs
of the City. The three primary categories that were evaluated were: 1) Ozone generator type (conventional
vs. modular); 2) Delivery method (fine bubble diffusion vs. direct or side-stream injection); and 3) Oxygen
source (onsite air prep. Vs. liquid oxygen (Lox).
Each category was evaluated on the following eleven criteria:
1. Construction Cost
2. Constructability (ability to maintain operation during construction)
3. Manufacturer Support/Parts Availability
4. Proven Performance
5. Ability for the system to adapt to varied ozone demands
6. Safety
7. Ease of Operation
8. Resiliency/Redundancy
9. Maintenance
10. Energy Efficiency
11. Expandability
Measure Description
The focus of this measure is to replace the existing ozone system with a new system that offers improved
reliability, functionality and uses less energy to operate when compared to the existing system. As part of this
ECM, a variety of replacement alternatives were evaluated to identify the preferred approach. From this
evaluation PG&E/Southland recommends replacing the existing ozone generators with modular Primozone
ozone generators by Pureflow Ozone Division. The new generators will be fed by new LOx storage and
delivery systems. The Scope of Work for the recommended improvements are summarized below:
Scope of Work
The existing ozone system would be replaced in its entirety with a new turnkey system which will include all
components necessary for a complete functioning system. Refer to Appendix F for plans and specifications.
As this is a replacement of a critical system in an operating plant, careful consideration was given to the
planned approach. It is understood that the WTP must remain in operation at all times during construction.
The construction shall be accomplished in four phases: Phase 1 Demolition; Phase 1 Construction, Phase 2
Demolition; and Phase 2 Construction. Ozone generators #1 and #2 and destruct Unit #2 shall remain fully
operable during Phase 1 until the new system is online and accepted by the owner.
For the construction phase, a written schedule outlining the proposed phasing and sequence of the work
will be developed to ensure that the WTP remains in operation during the duration of the construction, with
the exception of approved nighttime shutdowns. An example phasing sequence is shown below as an
example and will be refined prior to construction.
Phase 1 Demolition
1. Existing Ozone Generator #3 and PSU #3. Disconnect and temporarily plug cooling water supply
and return lines to extents shown on the drawings. Remove cooling water supply and cooling water
return lines to extents shown on the drawings (and as amended in the drawings with Addendum
#7. See Appendix F.). Disconnect and remove conduit and conductors in generation room to
extents shown on the drawings. Remove unused overhead conduit and conductors to source.
2. Cooling water pump and appurtenances, Gen #3.
3. Compressed air piping in generator room, Gen #3. Disconnect and remove condui t and conductors
in generation room to extents shown on the drawings. Remove unused overhead conduit and
conductors to source.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 21
4. Feed gas ozone analyzer #1, compressor room.
5. Ambient ozone analyzer #1, ozone generators room.
6. Vent piping in generator room, Gen #3. Repair roof as necessary .
7. DRY-2. Protect equipment slab.
8. Equipment pads – Gen #3, PSU #3. Plug all floor penetrations. Repair tile floor after construction
of new generator equipment pads.
9. Four-inch SS ozone piping to Basin #1. Protect in place existing pipe hangers and supports. Re-
use as available. Four-inch SS piping to Basin #2 shall remain in operation During Phase 1.
Demolish two-inch ball valves and flow meters to Basin #1 at Contact Basin.
10. Ozone diffusers and manifold, Basin #1. Demolish blind flange and piping entering Basin #1, protect
wall sleeves in place.
11. Dissolved ozone sampling system, Basin #1. Demolish piping and meters, Basin #1.
12. Ozone Destruct Unit #1. Demolish to extents shown on the plans.
13. Remove three (3) air compressors from the existing foundations to facilitate installation of the new
chillers. The existing air compressor foundations will remain for use with the new chillers. Safe off
and disconnect compressed air piping, cooling water supply and return piping, power and controls.
See drawings for Addendum #7 in Appendix F.
14. Provide temporary compressed air to maintain operation of the existing ozone system during
installation of the new chillers. The temporary compressed air system will remain in place and
operational until the new ozone system is operating reliably . See drawings for Addendum #7 in
Appendix F.
Phase 1 Construction
1. Ozone Generators 1-6, place on housekeeping slab.
2. 45 kVA Ozone transformers 1-6, place on housekeeping slab.
3. Ozone Master Control Panel.
4. Two-inch welded 316 SS piping from ozone generators 1-6 to Basin #1.
5. LOx receiving station, storage tank, and evaporator systems (includes buried piping and indoor piping.
6. Gaseous oxygen (GOx) piping and conditioning manifold.
7. Feed gas ozone analyzer #1, compressor room.
8. Ambient ozone analyzer #1, ozone generators room.
9. LOx boost equipment pad.
10. LOx boost system consisting of single air compressor and associated piping.
11. LOx boost system piping to GOx piping.
12. Dilution air compressor #1 .
13. Dilution air prefilter board (Temporary installation).
14. Dilution airflow controller board (Temporary installation).
15. Dilution air piping to ozone piping.
16. DM-100 Ozone Destruct unit (Basin #1).
17. Contactor header piping and diffusers (Basin #1).
18. Dissolved ozone sampling system (Basin #1).
19. Ozone distribution module (Basin #1).
20. Chillers 1, 2, and 3 on existing air compressor foundations in compressor room.
21. Chilled water supply and return piping system for the ozone generators and chillers consisting of
4-inch insulated 304 SS main piping per the plans and specification section 402076 and 404210
(Grooved-end fittings. Re-use existing pipe hangers where appropriate), and as amended in the
drawings in Addendum #7. See drawings for Addendum #7 in Appendix F.
22. 300 gallon chilled water buffer tank on housekeeping slab (Wessels 300 gal CBT-300).
23. Remove unused equipment pads, compressor room.
24. Install new cooling water supply and return piping to chillers 1, 2 and 3 per the drawings in
Addendum #7. See drawings for Addendum #7 in Appendix F. Flush the cooling water system
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 22
piping to prevent debris from reaching the WTP’s media filters. Disinfect new cooling water piping
per AWWA C651.
25. Install new power and controls for chillers 1, 2 and 3 per the drawings in Addendum #7. Note: Each
of the water-cooled chillers included in this ECM includes a chilled water circulating pump within
the chiller package and is equipped with a single-point power connection (the pump is powered
within the chiller’s electrical system). As a result, the separate electrical circuit and starter for each
pump is not required as shown in the drawings in Addendum #7. The price of the ECM reflects the
chiller integrated pump and single-point power connection.
Phase 2 Demolition
1. Ozone Generator2 #2 and #3, and PSU #2 and #3.
2. Demolish cooling water supply and return piping in the air compressor room as indicated in the
plans and amended in the drawings in Addendum #7.
3. Four-inch SS ozone piping to Basin #2 (Protect in place existing pipe hangers and supports. Re -
use as available. Demolish 2 inch ball valves and flow meters to Basin #2 at Contact Basin).
4. DRY-1, protect equipment slab.
5. Feed gas ozone analyzer #2 (compressor room).
6. Ambient ozone analyzer #2 (compressor room).
7. Air receiver #1 and #2.
8. Compressed air aftercoolers #1 and #2.
9. High Pressure Air piping.
10. Ozone diffusers and manifold, Basin #2. Demolish blind flange and piping entering Basin #2, protect
wall sleeves in place.
11. Dissolved ozone sampling system, Basin #2.
12. Ozone Destruct Unit #2. Demolish to extents shown on the plans.
Phase 2 Construction
1. Repair tile floor, ozone generators room.
2. Two-inch welded 316 SS piping from ozone generators 1-6 to Basin #2.
3. Feed gas ozone analyzer #2 (compressor room).
4. Ambient ozone analyzer #2 (compressor room).
5. Dilution air compressor #2.
6. Dilution air prefilter board (final installation).
7. Dilution airflow controller board (final installation).
8. DM-100 Ozone Destruct unit (Basin #2).
9. Contactor header piping and diffusers (Basin #2).
10. Dissolved ozone sampling system (Basin #2).
11. Ozone distribution module (Basin #2).
12. Repair floor (compressor room).
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 23
Table 4.1: Ozone System Major Equipment List
Item Quantity Furnished by Manufacturer Model Number
LOx Tank 1 Southland Praxair
Vaporizers 2 Southland Praxair
GOx Regulating Manifold 1 Southland
Water Cooled Chillers 3 Contractor ArctiChill PWCCPV0250D4-DS1
Chilled Water Buffer Tank 2 Contractor Wessels
Dilution Air Compressor 2 Southland
LOx Boost Compressor 1 Southland
Ambient Ozone Meters 2 Southland Teledyne 456
Ozone Feed Meters 2 Southland Teledyne 456
Ozone Destruct Meter 1 Southland Teledyne 456
Dissolved Ozone Meters 2 Southland Rosemont 1056
Dewpoint Analyzer 2 Southland Kahn
45 kVA Transformers 6 Contractor
Ozone Generators 6 Southland Pureflow GM-48
Ozone Destructors 2 Southland Pureflow DM-100
Ozone Distribution Module 1 Southland Pureflow ODM
Three-inch all-Ceramic Diffusers 200 Southland Filtros FA030
Three-inch all-Ceramic Diffusers 12 Southland Filtros FA050
Energy and Lox Usage Analysis of Proposed Ozone System
PG&E/Southland performed an analysis of the new ozone system to determine its annual energy use, LOx
use and resulting operating costs. The analysis involved characterizing the WTP’s ozone production for a
year of operation, and then applying the energy, cooling and LOx consumption characteristics of the new
ozone equipment to the profile to determine the energy and LOx use. The ozone production profile was
established by estimating the ozone output rate from the existing ozone generators (OG) based on their
rated ozone output rate (pounds per day, PPD), rated electrical input power (kW) at the rated ozone output,
and the actual power (kW) applied to the ozone generators. We measured and recorded the power input
to each generator in 15-minute intervals for a year which provides the foundation for an annual profile. The
formula used for estimating the instantaneous ozone generator output rate is:
Ozone Output Rate = OG Rated Output (PPD) × Actual OG Power Input (kW) ÷ OG Rated Power (kW)
The OG rated output used in the analysis is 250 PPD and the rated power input is 80 kW.The resulting
ozone production profile indicated an average OG production rate of 192.9 PPD when the OGs are
operating, and a total weight of ozone produced for the year of 46,529 pounds (which is an average of
127.5 pounds each day).
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 24
The energy, cooling and LOx consumption characteristics of the new ozone equipment were applied to the
profile to determine the required energy and LOx for the new system while satisfying the same ozone
production requirements as the existing system. The results are summarized in the following tables.
Charts of the calculated daily average OG output rate and the daily total ozone production rate and the
ozone production calculations are located in Appendix C.
Benefits
The expected benefits of this ECM include:
• Reduced energy consumption.
• Replacement of aging, obsolete ozone equipment and components.
• Improved ability to perform maintenance.
• Improvement in reliability of achieving permit compliance.
• Increased reliability and redundancy.
• Reduction of GHG emissions resulting from the City’s operations.
• Contribution to the City’s sustainability goals and advancement toward ZNE.
Equipment
Baseline
Energy Use
(kWh/year)
Post Retrofit
Energy Use
(kWh/year)
Energy
Reduction/
Savings
(kWh/year)
Ozone Generators/PSUs 372,930 246,429 126,501
Ozone Air Compressors 492,653 2,739 489,914
Ozone Destruct Units 44,060 44,060 0
Ozone System Chillers & Pumps 0 75,405 -75,405
Total 909,643 368,633 541,009
LOx Use
(SCF/Year)
LOx Cost per
100 SCF
(HSCF)
Cost of LOx
Commodity
per Year ($)
Delivery
Cost,
Each ($)
Quantity
of
Deliveries
per Year
Total
Delivery
Cost per
Year ($)
Total LOx &
Delivery
Costs per
Year ($)
3,891,531 0.95 36,970 150 12 1,800 38,770
LOx Use and Cost Summary
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 25
4.2.2 ECM-4 WTP Transfer Pump Station Upgrades
Existing Conditions
As discussed above, the TPS houses four (4) transfer pumps that ultimately
provide treated water to the City’s high-pressure distribution system. This is
accomplished by pumping water from Clearwell #1 to Reservoir-2 which in
turn gravity feeds the high-pressure system. The high-pressure system can
be directly served from the transfer pumps in the event Reservoir-2 is taken
offline. The only event in which the high-pressure system would be directly
pumped is if Reservoir-2 would be taken offline for maintenance or to be
rebuilt as recommended in the City’s 2015 Potable Water Distribution System
Operations Master Plan. If the high-pressure system is directly fed and
demand is fluctuating, there is no way to regulate the system flow other than
manually turning system pumps on and off.
For system control, the TPS building is currently equipped with a Bristol Babcock 3300 Distributed Process
Controller (DPC) that is integrated into the facility wide SCADA system. For operation and monitoring of the
four transfer pumps, each is currently set up for remote starting, and alarm monitoring via the SCADA
system. In addition to pump control and monitoring, the system supply pressure and flow is monitored by
the SCADA system. Because Reservoir-2 has a storage capacity to serve the City’s high-pressure system
for two to three days (depending on demand) there is currently not an automated process utilized through
the SCADA system to operate the Transfer pumps. On average three pumps are operated manually by the
plant operators based on when the WTP is in operation which averages 16 hours per day.
Measure Description
As the City’s primary mission in the operation of the WTP is providing reliable safe water service, careful
consideration should be given to determine the most effective approach to modifying and controlling the
TPS. PG&E/Southland recommends the addition of Variable Frequency Drives (VFDs) to each of the four
existing transfer pumps and improved pump sequencing – the combination of which is expected to improve
overall system efficiency.
The two primary benefits include the ability to slowly ramp up each pump when they are brought online to
eliminate pressure spikes and the ability to continually modulate the pump speed to meet varied demands
of the high-pressure system.
Another recommendation to manage the operational costs of the TPS is to integrate level sensing at
Clearwell #1 and pump sequencing to minimize the energy consumption relate d to serving Reservoir-2.
This would include the strategic operation of pumps based on energy usage, energy rates, and tank levels.
Scope of Work
• Install a wall-mounted Allen Bradley or ABB VFD for each of the four existing transfer pumps and
integrate the VFDs into the SCADA system. Each VFD will be configured with a bypass, disconnect
switch, line reactor and communication interface compatible with Allen Bradley CompactLogix
controllers. The City will select the preferred VFD during final design.
• Modify the existing hardwired controls for the transfer pumps and their discharge valves to function
with the new VFDs.
• Integrate the existing tank level sensor at the Bishop Storage tank to monitor the high-pressure
system.
• Add sequence of operation in the SCADA system to allow for automatic operation of the Transfer
pumps to directly serve the high-pressure system when Reservoir-2 is out-of-service or
disconnected from the system.
Figure 4.2: TPS Controller
(CSP)
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 26
• Add programming to the TPS control system with logic to optimize the operation of the pumps when
serving Reservoir-2 based on Clearwell Levels, Reservoir-2 levels and Time-of-Use (TOU) electric
rates.
Benefits
The expected benefits of this ECM include:
• Optimized system sequencing and function with or without Reservoir-2 online.
• Reduced staff requirements for manual operation.
• Provide the ability to reduce disinfection by-products related to water age issues in the Water
Distribution System (WDS).
4.2.3 ECM-9 WTP Plant Service Water System Upgrades
Existing Conditions
The Plant Service Water System (PSWS) provides treated water to a number of processes and uses in the
WTP including cooling water for equipment, plant water, domestic water, and irrigation. The PSWS consists
of a Flowtronex packaged booster pump system (BPS) located in the Pump Station building near Clearwell
#1, a network of distribution piping in the WTP downstream of the BPS, and an 8” pipe connection to the
High-Pressure Zone that is the source of treated water to the system. The Flowtronex BPS is designed to
deliver 550 GPM at a discharge pressure of 90 psig and includes a skid with two constant speed 30 HP
end-suction centrifugal pumps, a constant speed 3HP vertical turbine pump (“jockey” pump) rated for 60
GPM, suction and discharge piping, pump discharge pressure control valves, electric power control
components, and instrumentation and controls. One-30 HP pump operates during normal WTP operation
and the “jockey” pump operates when service water demands are low (usually when the water treatment
process is off).
The predominant service water use appears to be the cooling water (CW) system that provides cooling for
the ozone generators, ozone power supply units (PSUs), air compressors for the ozone system , and
compressed air aftercoolers. When equipment connected to the CW system is operating, its CW valve is
opened allowing CW to flow from the CW supply piping through operating equipment, removing heat. The
equipment’s CW valve is closed when the equipment is off. The CW leaving the equipment flows into the
CW return piping and is ultimately sent to the plant for re-treatment via connection to the filter inlet channel.
Flow Evaluation
The operator’s logs for January 2017 through October 2017 show the service water flow rate averages
roughly 280 GPM during plant operation and the average suction pressure at the pump skid is
approximately 65 psig. As part of the IGA, two temporary ultrasonic flowmeters were installed
simultaneously to confirm the total service water flow rate in the operator’s logs and to determine the flow
rate used by the CW system. The flowmeter for the total system flow was installed on the main PSWS pipe
leaving the pump house.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 27
The flowmeter for the CW system was installed on the common CW return pipe between the air compressor
room and the pipe gallery. Each flowmeter was configured to record the flow rate at one-minute intervals.
The data for the total service water flow rate showed an average flow rate of 269.3 GPM during water
treatment operations, confirming the values in the operator’s logs. The data for the CW system showed an
average CW system flow rate of 241.9 GPM during treatment operations. The average service water flow
rate after water treatment operations was 49.0 GPM and the average CW flow rate during those periods
was 44.9 GPM. See Figure 4.4 for a chart of measured flow data. The outcome is that 89.8 percent of the
service water flow is used by the CW system during treatment operations, resulting in only 27.4 GPM going
to other water demands in the WTP. Similarly, 91.6 percent of the service water
flow goes to the CW system after treatment operations, indicating only 4.1 GPM
serves other water demands in the WTP. These findings also indicate that most
of the energy used by the PSWS is related to the generation of ozone
(disinfection process) and that energy use will be reduced with installation of
the new ozone system that utilizes a closed loop cooling system with water-
cooled chillers.
In addition, after installation of the new ozone system, the existing BPS will be
ill-configured for the revised cooling water system demands and remaining
after-treatment service water demands, and the PSWS is not expected to
operate properly as a result. The expected typical PSWS flowrate during
treatment operations after the ozone upgrade is 154.4 GPM which includes
cooling water for two chillers at their rated flow of 63.5 GPM each and 27.4
GPM for other WTP service water demands. This flow rate does not leave much
margin to the minimum flow rating for the existing main BPS pumps of 100
GPM. It is likely that the PSWS flow rate will fall below the 100 GPM minimum
when the chiller cooling water control valves reduce flow during periods of low
cooling water supply temperatures (which is expected in winter). The jockey
pump is rated for 60 GPM and has a minimum flow rating of 10 GPM. It does
not have the capacity to provide cooling water for the new chillers, and will not
be able to turndown to the 4.1 GPM flow rate at night.
Figure 4.3: Plant Service
Water System Booster
Pumps
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 28
Figure 4.4 Measured PSWS and CW Flow Rates
Baseline Energy Analysis
As part of the IGA, temporary instrumentation was installed to measure and record the energy use and
hours of operation for each of the three existing BPS pumps. The measurements were recorded for one
year. The result of the data analysis shows that the BPS operates continuously, and the pumps consume
96,703 kWh per year. Additionally, pumps P1 and P2 operate for 6,134 hours and consume 89,7787 kWh
per year, and the jockey pump operates for 2,626 hours and consumes 6,916 kWh per year. Utilizing the
results of the PSWS flow analysis, 86,989 kWh per year of the BPS use is attributable to the CW system
and will be eliminated when the new ozone system is installed. A chart of the daily energy use, and the
energy calculations are located in Appendix C.
Evaluation of the BPS pressure control system and pumps reveals that a significant portion of the energy
used by the main pumps is wasted through each pump’s discharge pressure control valve. The pump curve
for the main pumps shows the pump produces 152 feet of head (65.8 psi) at 280 GPM which results in a
pump discharge pressure of 130.8 psig (when the suction pressure is 65 psig). This is significantly more
than the 90 psig PSWS pressure set-point that the booster pump package is attempting to satisfy. As a
result, the excess 40.8 psi of pressure is throttled (wasted) down to the set -point by the pump’s discharge
pressure control valve. The generation of excess pressure wastes of 62 percent of the energy used by the
pump. Variable speed control of the pumps in-lieu of the pressure control valve would eliminate the energy
loss caused by throttling.
BPS Phase Fault and Power Quality Study
An ongoing problem with the BPS is an electric “phase fault” that causes the BPS to shut down
approximately ten to twelve times per year. This failure causes the loss of cooling water to key ozone
system equipment that usually results in shut down of the ozone system, and ultimately the water treatment
process. The phase fault is internal to the BPS controls a nd utilizes a 3-phase voltage sensor to monitor
overvoltage, voltage imbalance, phase loss and phase reversal. If conditions are outside the set-points in
the monitor, the monitor provides a single contact output to the BPS controller that in turn generates the
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 29
fault and shuts down the system. The specific electrical condition(s) that have triggered previous phase
faults are not known since the monitor does not indicate the cause of the fault.
As part of the IGA, the SST team engaged PG&E’s Power Quality team (PQT) to commission a power
quality study to see if the cause of the faults could be determined. The PQT agreed to perform a study and
installed power quality meters in four locations: On the main electric service to the WTP at the meter; On
the 480V power supply to the main switchboard; On the 480V power supply to MCC-5 that serves the BPS;
and on the 480V power supply in the BPS control panel. BPS phase faults occurred during the study period,
but potential triggers/events were not identified in the data from the meters. The report from the PQT is
located in Appendix H.
Measure Description
The proposed solution is to replace the existing BPS with a new packaged BPS that is sized for the lower
flow rates that will occur after the replacement of the ozone system. The new BPS will utilize variable speed
pumps to efficiently maintain the required system discharge pressure and the system will include a
pressurized diaphragm tank that will discharge water to the PSWS when the pumps shut off during low
demand conditions. The proposed BPS is manufactured by Grundfos, model Hydro MPC-E 3CRE. The
factory assembled system includes three variable speed, multistage vertical inline pumps with integrated
motor/VFD rated for 228 GPM each, suction and discharge piping, and a control panel.
The scope of work includes :
• Removal and disposal of the existing booster pump system and control panel.
• Furnishing, installing, start-up and commissioning the new booster pump system and diaphragm
tank.
• Provision of temporary booster pump service for the PSWS during demolition of the exist ing system
and installation of the new system.
See Appendix H for the drawing showing the proposed work and the submittal for the proposed booster
pump system and diaphragm tank.
Benefits
The expected benefits of this ECM include:
• An appropriately sized and configured booster pump system for the PSWS after the CW system
demands are modified with the new ozone system.
• Renewal of the aging existing BPS.
• A small reduction in electrical use, demand, and related costs versus a booster pump system
utilizing pressure control valves for pressure control.
• Reduced maintenance efforts resulting from use of variable speed pumps instead of pump
discharge pressure control valves (Cla-Val valves) for pressure control.
• Contribution to the City’s sustainability goals and advancement toward ZNE.
• Reduction of GHG emissions resulting from the City’s operations.
4.2.4 ECM-11 WTP SCADA/Controls Upgrades
Existing Conditions
The WTP is equipped with an existing SCADA system which is utilized by the City’s staff to monitor and
control key equipment and processes at the WTP. This system is equipped with 10 Control System
Processors which are Bristol Babcock DPC RTU controllers of varying vintage (1994–2008). These
controllers located at multiple locations around the plant are networked back to operator workstations in the
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 30
WTP’s control room via Cat-5 or Fiber optic cabling. The main operator workstation is equipped w ith iFIX
interface software as well as IFIX historian for trending and archiving key parameters need ed for system
operation and regulatory compliance.
The existing system as described above is confined to the WTP at Stenner Creek Road and currently has
no capability for remote access or interface with systems outside of the plant. In addition , the existing Bristol
Babcock system controllers are an aging obsolete platform with limited availability of spare parts and
service providers which results in continually rising maintenance costs.
The City has recently completed a SCADA upgrade project on the components and systems associated
with the Water Distribution System (WDS), which is fed from the WTP. This upgrade project included a
systemwide migration to the Allen Bradley family of controllers. Migrating the entire WDS to a common
platform provided the City with the ability to monitor and control the system as a whole on a unified platform.
The WTP was not part of this migration and will not have the ability to send or receive information from the
WDS.
Measure Description
The objective of this measure is to improve the existing SCADA system at the WTP by upgrading the
existing controllers to a platform that is compatible with the system recently installed on the WDS. This
would provide the ability to monitor the connected systems that make up the WDS, which will provide the
ability to monitor and optimize the control of the WTP and WDS as a system.
Scope of Work
PG&E/Southland recommends the replacement of the existing Bristol Babcock controllers with
CompactLogix and/or ControlLogix Programmable Logic Controllers (PLCs) by Allen-Bradley. Compact
Logix and Control Logix represent small and large PLCs from the same family. They are fully c ompatible
with each other and use the same programming software. The description of the system
replacements/upgrades is described below.
• At the Ozone building CSP-1 and CSP-7:
o These existing controllers and associated infrastructure will be removed. One new
integrated Ozone controller will be provided and installed in conjunction with the Ozone
system upgrade described in ECM-2. This new controller will be provided with the
following:
▪ Provide a new cabinet and custom back panel
▪ The new integrated Ozone controller will be an Allen Bradley PLC
▪ Add a new power supply and uninterruptable power supply
▪ Provide new Ethernet switch
▪ Provide new terminal blocks, Relays, Fuses as required
• At the Ozone contact basin CSP-2:
o This existing controller and associated wiring will be removed as it will no longer be
needed for the new Ozone system upgrade installed as part of ECM-2
• At the Filter Building CSP–3 and CSP-4:
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
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• At the Chemical Building CSP-5: replace with new PLC in the existing cabinet and location.
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
• At the Plant Water Service Pump Station CSP-6:
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
• At the TPS CSP-8:
o Provide a new custom back panel for installation in the existing PLC cabinet
o Replace existing controllers with a new Allen Bradley PLC
o Add a new power supply and uninterruptable power supply
o Provide new Ethernet switch
o Provide new terminal blocks, Relays, Fuses as required
• All of the upgraded PLCs listed above will be reprogrammed with existing sequences, alarms and
trending.
• To optimize operator interface, two (2) Portable computer tablets (Apple Ipad or equal) will be
provided with Graphic interface software.
As the existing Actiflo System controllers CSP 9 and CSP10 are the newest and were provided and
programmed by the manufacturer as a proprietary system package, it is recommended that these remain in
place. A small number of interface points from this system were integrated into the SCADA system at CSP-3
from the Actiflo system. These interface points would be re-established as part of the CSP-3 upgrade.
Benefits
The expected benefits of this ECM include:
• Providing a robust SCADA system that utilizes a centralize d communication and control protocol
will provide the City the ability to monitor the potable water system (treatment and distribution) and
optimize operation as a connected system.
• Providing critical process information of connected systems to evaluate and improve process
operations and efficiency.
• Providing a PLC and associated communication specification for future upgrades or expansion
which will avoid the costs associated with integrating mismatched systems.
• Allowing the City to consider PLC related services from multiple vendors as the Allan Bradley
product is one of the most common in the industry.
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4.3 Phase 2 (Resiliency) ECMs
Four ECMs are recommended for further evaluation/implementation as Phase 2 (Resiliency) of the City’s
Water Energy Efficiency Project. To assist the City with moving toward an energy neutral WTP, as well as
contribute to the City’s sustainability goals and advancement toward Zero Net Energy, the Water Energy
Efficiency project looked for opportunities to generate energy on-site from renewable sources including
hydrogeneration and solar. Due to infrastructure priorities, such as the need to provide broader ba ck up
power capability in the event of a Public Safety Power Shutdown event by the utility, and budgetary
constraints, staff is not proposing to move forward with the resiliency phase measures at this time.
Description of potential solutions for Phase 2 ECMs that were developed prior to formation of the current
resiliency strategy are located in Appendix L.
4.4 Other ECMs
Four ECMs are not recommended for further evaluation/implementation. This recommendation is based on
the cost to implement versus the benefit provided to the City which makes these ECMs unattractive. In the
case of the Reservoir #1 photovoltaic measure, this was considered under a different program.
4.4.1 ECM-6 WTP Photovoltaic Shade Canopy for Actiflo and Filter Basins
Existing Conditions
The WTP currently does not utilize renewable energy resources to displace grid supplied energy and reduce
the WTP’s utility costs. Additionally, the Actiflo and filter basins are exposed to the sun for most daylight
hours which can promote algae growth in these systems.
Measure Description
The focus of this energy conservation measure is to reduce the City’s consumption of energy from the utility
and the related costs by installing photovoltaic (PV) generation systems at the WTP. An additional goal of
this measure is to reduce exposure of the Actiflo basins and filters to the sun to reduce conditions for algae
growth and algae related disinfection byproducts in these areas of the process.
The initial envisioned solution is the installation of two canopy mounted PV arrays, one 30 kW DC array over
the Actiflo basins and a second 35 kWDC array over the Filters. This system will be able to produce
approximately 100,000 kWh annually which will offset approximately 4.7% of the WTP’s current
consumption.
Additional Considerations
• Energy generated by PV systems directly connected to the WTP has the best economic value
($/kWh) versus utilizing bill credit transfers (BCT) from excess generation at another of the City’s
sites.
• The WTP experiences periodic power quality type issues that affect systems in the WTP and could
affect the electronics in PV system inverters. Further investigation to understand and characterize
the issues will be required.
Benefits
The expected benefits of this ECM include:
• Reduced electric utility costs.
• Renewable generation of 4.7% of the WTP’s current consumption.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 33
• Improved water quality and human health due to reducing the potential for algae growth.
• Contribution to the City’s sustainability goals and advancement toward ZNE.
• Reduction of GHG emissions resulting from the City’s operations.
4.4.2 ECM-13 Install VFDs for Ferrini Pumps and Eliminate Fel Mar Pump Station
Existing Conditions
In 2013, the City removed the Highland Tank and improved the Rosemont Pump Station. In order to
facilitate the removal of the Highland Tank, the following additional projects were recommended to improve
fire protection, system pressures, reliability, and redundancy:
• Raise operating level in Ferrini Tank to one foot from the overflow elevation
• Abandon the Fel Mar Pump Station
• Combine the Highland and Ferrini Pressure Zones by adjusting the settings of the Skyline and
Patricia PRVs
The City also planned to modify the Ferrini Pump Station to allow the pump station to provide service to the
combined Highland/Ferrini Zone when the Ferrini Tank is out of service. These modifications were
anticipated to include a pressure relief valve and bypass piping located within the Ferrini Pump Station.
The Fel Mar pump station was scheduled for removal once the Highland tank was removed. Dur ing hydrant
tests performed by City staff on September 19, 2008, it was found that the Fel Mar pump station (rated at
600 GPM at 170’ TDH) contributes only slightly to the fire flows at the upper elevations of the Highland
Zone. It was estimated that the Fel Mar pump station contributes approximately an additional 100 GPM
near the Rosemont pump station. However, since the Fel Mar pump station pumps directly into the Highland
zone, it was found that the pressure provided by the Fel Mar pump station causes the PRVs at Patricia and
Skyline to close, thereby eliminating the benefit of the Ferrini tank and pump station in an emergency (Fel
Mar pumps from the Patricia zone which is supplied by the small Serrano tank). Several strategies involving
the Fel Mar pump station were considered such as leaving it in service as backup to the Ferrini tank to
supply the Highland zone, or as a future dedicated booster pump station to provide fire flow to the Rosemont
pump station. Ultimately, it was determined that the Fel Mar pump station should be taken out of service,
as planned.
Subsequently, the 2015 Water Master Plan recommended that the recently-constructed Rosemont Pump
Station be eliminated, and a new Fel Mar Pump Station be constructed, and fitted with a fire pump a nd
backup generator. The recommendation was based on a stated requirement to fill a future Rosemont Tank
in eight hours, and “low suction pressures at Rosemont Pump Station that impact the ability to meet fire
flow requirements in the Highland Zone.” Addit ional pipeline upgrades were also recommended.
Measure Description
The focus of this measure was to evaluate potential modifications to the distribution system to improve
operations and reduce planned CIPs. Specifically, th is ECM evaluated the potential to install VFDs at the
Ferrini Pump Station, and an altitude valve at the Ferrini Tank. These improvements, combined with VFDs
integrated into the new SCADA system, were evaluated to determine if the Ferrini Pump Station could
potentially be used to increase suction pressure at the Rosemont BPS, and to provide a mechanism to
supply the Highland zone when the Ferrini Tank is out of service.
Based on our review of the system configuration, it is not recommended to raise the hydraulic grade in t he
highland zone by installing an altitude valve on the Ferrini Tank and using the Ferrini pump station to deliver
water to the Highland zone. Although this configuration may increase the suction pressure at the Rosemont
pump station, the Ferrini tank would be effectively isolated (altitude valve held closed) by the Ferrini pumps.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 34
This would result in high water age and lack of turnover in the Ferrini tank. This approach could be
considered as a mechanism to taking the Ferrini tank out of service fo r repairs or for future removal of the
tank, but it is not recommended as a method to raise the grade in the highland zone. It is our understanding
that staff has addressed the accumulation of air at the Rosemont pumps due to low suction pressure by
installing air release features on the piping.
Additionally, based on utility records from 2015-2017, the electrical costs associated with the Ferrini Pump
Station have increased 140 percent, though the energy use (kWh) has remained nearly identical. This
increase appears to be due to the change in rate tariff from A1 to A10 (Effective November 1, 2012,
Schedule A-1 is closed to customers with a maximum demand of 75 kW or greater for three consecutive
months in the most recent twelve months). The peak demand a t Ferrini was at 79-81 kW for a number of
months, which initiated the A-10 Tariff. For the period of late 2016 through most of 2017, the peak demand
has been 48-49 kW. For this ECM, VFDs and other instrumentation/controls will be evaluated to control the
pumps in a way to keep the demand below the 75-kW threshold and maintain the A-1 tariff.
Benefits
The expected benefits of this ECM include:
• Elimination of new Pump Station and Pipeline CIPs.
• Reduced pumping costs through VFD control and reduced “double pumping.”
• Reduced pumping costs through maintaining a lower tariff.
• Retaining full life-expectancy of existing Rosemont Pump Station (built in 2010) resulting in avoided
capital costs of $745,000.
• Improving fire protection.
• Reduced operations and maintenance (O&M) by consolidating existing facilities, resulting in
reduced O&M costs of $8,000 per year.
4.4.3 ECM-15 Reservoir No.1 Photovoltaic Energy Generation
Existing Conditions
The City’s Water Distribution System (WDS) facilities currently do not utilize renewable energy resources to
displace grid supplied energy and reduce the Utilities Department’s utility costs. The Reservoir No.1 site has
a large amount of open area surrounding the reservoir that could be utilized for a solar photovoltaic system.
Measure Description
The focus of this energy conservation measure is to reduce the City’s consumption of energy from the utility
and the related costs by installing a PV generation system at Res ervoir-1.
The initial solution explored for this site is the installation of a large, 1,200 kWDC, ground-mount PV array in
the open area to the north and east of the reservoir (see Figure 4.10, below). This system will be able to
produce approximately 1,860,000 kWh annually which is significantly more than the 10,800 kWh that is
consumed at Reservoir-1. The excess (exported) energy generation will be used to reduce electric utility
costs at other Utilities Department and City facilities through PG&E’s Renewable Energy Self-Generation
Bill Credit Transfer (RES-BCT) rate schedule for local government. The output from this PV system will
offset approximately 58.5% of the total electric consumption for all of the Water Utility’s facilities (water
supply, treatment and distribution).
Additional Considerations
PG&E has proposed changes to its TOU structure and rates, including A-1 that applies to Res-1, that will
ultimately reduce utility cost savings for PV systems relative to the existing rates. On October 26, 2017 the
CPUC approved Decision 17-01-006 that provides “grandfathering” of the current TOU rate periods for
public agencies who submit a solar PV interconnection application (IA) prior to December 31, 2017. The
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 35
grandfathering extends the current TOU periods to July 31, 2027. In order to secure TOU grandfathering
for PV at Reservoir No. 1, Southland submitted an IA to PG&E on behalf of the City on December 22, 2017
for PV systems with a total capacity of 960 kWAC (1,200 kWDC).
Benefits
The expected benefits of this ECM include:
• Significant reduction in electric utility costs.
• Renewable generation that replaces approximately 58.5% of the total electric consumption for all
of the Water Utility’s sites.
• Significant contribution to the City’s sustainability goals and significant advancement toward ZNE.
• Reduction of GHG emissions resulting from the City’s operations.
Figure 4.5: Reservoir-1 PV Site Plan
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4.4.4 ECM-16 Whale Rock Pump Station Upgrades
Existing Conditions
One of the raw water sources for the WTP is Whale Rock Reservoir. Whale Rock Reservoir is located on Old
Creek Road approximately one-half mile east of the community of Cayucos. The project was planned,
designed, and constructed under the supervision of the State Department of Water Resources. Construction
took place between October 1958 and April 1961. The reservoir is jointly owned by the City, the California
Men’s Colony (CMC), and the California Polytechnic State University at San Luis Obispo (Cal Poly). These
three agencies form the Whale Rock Commission which is responsible for operational policy and
administration of the reservoir. Day-to-day operation is provided by the City of San Luis Obispo.
The conveyance system delivers water from the reservoir to the Whale Rock Commission member
agencies located between the reservoir and the WTP. Outlets from the pipeline exist for water deliveries to
Chorro Reservoir and WTP (operated by the California Men's Colony), Cal Poly State University, the
Cayucos water treatment facility and the City's WTP. Currently, deliveries are regularly made to Cayucos,
the CMC, Cal Poly, and the City’s WTP.
The Whale Rock pipeline is approximately 17 miles long, connecting the reservoir to the member agencies,
and terminates at the City's WTP. The design capacity of the pipeline is 18.94 cubic feet per second
(approximately 8,500 gallons per minute). The line consists of mo dified prestressed concrete cylinder pipe
at most locations. Cement mortar lined steel pipe is used at creek crossings and junctions. The pipeline
has surge protection consisting of eight-inch, globe type, diaphragm-actuated pressure relief valves which
protect the line from excessive pressures.
Two pump stations, arranged in series, move the water through the pipeline to the delivery points. The first
pump station (Pump Station A) is located in Cayucos at Chaney Avenue. The second (Pump Station B) is
located near Camp San Luis Obispo, approximately six miles southeast of Morro Bay. Each station has
five, parallel, constant speed 200 horsepower pumps. Upgrades to both pump stations, including the
addition of two pumps at each station, were completed in August 1993. Six pumps and motors were
replaced in 2004.2 (Note – the two pumps installed at each station in 1993 are equipped with VFDs, but the
VFDs are not used, and is not yet clear if they are operable). The SCADA system for the pump stations has
recently been upgraded, including new networked communications, as part of broader City SCADA upgrade
project.
When deliveries are made to member agencies, both pump stations operate simultaneously utilizing the
same quantity of pumps in each pump station. A single pump, or multiple pumps at each station may be
operated depending on the flow required to satisfy the requested deliveries.
The CMC typically requests deliveries daily and requires a flowrate of approximately 2,200 GPM for four to
six hours. This flowrate can be satisfied by operating one pump at each station (a pump set). However, the
capacity of one pump set exceeds the flow taken by the CMC during CMC only deliveries, and since the
WTP cannot control or limit the flow from the Whale Rock pipeline, the excess flow is delivered to the WTP.
Recent measurements at the WTP have determined that approximately 650 GPM is delivered to the WTP
during CMC deliveries. When Whale Rock water is not desired at the WTP during CMC deliveries, the pump
energy associated with the extra flow is wasted and the City is forced to receive water from its storage in
Whale Rock Reservoir.
2 City of San Luis Obispo 2010 Urban Water Management Plan
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Measure Description
The focus of this measure is to reduce energy use and improve the operation of the WTP by minimizing or
eliminating unneeded Whale Rock water deliveries to the WTP during CMC deliveries, and provide the
control of the flow to the WTP during specified WTP deliveries. The envisioned solution includes:
• Replacement of the two pump VFDs at each pump station, integration of the VFDs to the new
SCADA system at the pump stations, and implementation of new control logic/programming for
control of the pumps.
• Installation of a control valve in the 30” Whale Rock pipeline at the WTP, upstream of the connection
to the forebay. The new control valve will give the WTP the ability to prevent deliveries from the
Whale Rock pipeline when desired and control the Whale Rock delivery flowrate when deliveries
are desired.
• Integration of the new control valve with the WTP’s SCADA system and implementation of new
control logic/programming for control of the valve. Ideally, key status points for the valve would be
visible to the Whale Rock SCADA system for coordination of pump operation with the valve.
Benefits
The expected benefits of this ECM include:
• Reduces or eliminates unneeded Whale Rock deliveries at the WTP during CMC operation.
• Allows the WTP to specify a desired Whale Rock delivery flowrate that is less than the capacity of
a whole pump set.
• Reduced electrical use, demand, and related costs resulting from eliminating unneeded flow and
controlling the pumps to only produce the head needed for a given flowrate .
• Contribution to the City’s sustainability goals and advancement toward ZNE.
• Reduction of GHG emissions resulting from the City’s operations.
INVESTMENT GRADE AUDIT REPORT • CITY OF SAN LUIS OBISPO 38
5 APPENDICES
APPENDIX A: SST PROGRAM OVERVIEW
APPENDIX B: UTILITY ANALYSIS DETAILS
APPENDIX C: WTP ENERGY ALLOCATION AND ENERGY ANALYSIS DETAILS
APPENDIX D: WTP OZONE PILOT TEST REPORT
APPENDIX E: WTP TOPOGRAPHIC SURVEY & GEOTECH REPORT
APPENDIX F: ECM-2 WTP OZONE SYSTEM UPGRADE
APPENDIX G: ECM-4 TRANSFER PUMP STATION UPGRADE (VFDS FOR
TRANSFER PUMPS)
APPENDIX H: ECM-9 PLANT SERVICE WATER SYSTEM UPGRADE
APPENDIX I: ECM-11 WTP SCADA SYSTEM UPGRADE
APPENDIX J: IGA AND DESIGN COMMENTS
APPENDIX K: PROJECT CONSTRUCTION SCHEDULE
APPENDIX L: PHASE 2 (RESILIENCY) ECM DESCRIPTIONS