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Home My WebLink About04.b. Receive update on Central San solar energy opportunities Page 1 of 14 Item 4.b. CENTRAL SAN July 22, 2019 TO: REAL ESTATE, ENVIRONMENTAL AND PLANNING COMMITTEE FROM: MELODY LABELLA, RESOURCE RECOVERY PROGRAM MANAGER REVIEWED BY: JEAN-MARC PETIT, DIRECTOR OF ENGINEERING AND TECHNICAL SERVICES ROGER S. BAILEY, GENERAL MANAGER SUBJECT: RECEIVE UPDATE ON CENTRAL SAN SOLAR ENERGY OPPORTUNITIES Staff has hired the expert solar consulting firm, ARC Alternatives, to evaluate any remaining opportunities for solar energy use within Central San's overall operation. The attached presentation will be provided at the July 22, 2019, Real Estate, Environmental & Planning Committee meeting and includes an overview by staff on Central San's energy use and past efforts on solar energy, and concludes with a briefing by ARC Alternatives on the results of their analysis and a potential solar energy project for Central San to pursue. Strategic Plan re-In GOAL THREE: Be a Fiscally Sound and Effective Water Sector Utility Strategy 2- Manage costs GOAL SIX: Embrace Technology, Innovation and Environmental Sustainability Strategy 2- Reduce reliance on non-renewable energy ATTACHMENTS: 1. Presentation July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 16 of 46 Page 2 of 14 '{4 q + UPDATE ON POTENTIAL SOLAR ENERGY OPPORTUNITIES Melody LaBella, P.E. Resource Recovery Program Manager REEP Committee Meeting July 22, 2019 PRESENTATION OVERVIEW Background Central San's Power Usage Central San's Past Efforts on Solar Energy Solar Feasibility Briefing by ARC Alternatives July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 17 of 46 1 Page 3 of 14 WHERE IS POWER USED AT CENTRAL SAN? Treatment Plant Includes HOB, POB and the Lab Pumping Stations Household Hazardous Waste Collection Facility (HHW) CSO Building and Vehicle Maintenance Shop (VMS) Annex and Bays (4737 Imhoff Place) CENTRAL SAN HOW DOES CENTRAL SAN MEET THE POWER DEMANDS OF THE TREATMENT PLANT? Cogeneration System (Cogen) Meets -90% of plant's energy demand Grid power Used to meet peak demands Provides a reliable back-up SI 5 July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 18 of 46 2 Page 4 of 14 WHAT DOES COGEN DO? F- Naturalr Gas4a Electricity Produces —2.8 megawatts of power per day at a fully-loaded cost of $0.04 per kilowatt-hour CENTRAL SAN IS TYPICAL TREATMENT PLANT ENERGY USE PG&E Solids to 0.48% Incineration 34% Natural gas 53% Landfill gas 13% CENTRAL SAN I July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 19 of 46 3 Page 5 of 14 TREATMENT PLANT ENERGY USE IN 2018 20186reenhouse Gas Inventory Update(January 1-December31,2016) Estimated Anthropogenic GHG Emissions:23,789 Mt CO1e —Teta)Odle N64hdge +•Co QI3 NG WIN Usage —T-I MN L" I s, —v Llh[9rtlkw] —ural 9—fww lWhr 4APD W," 3,500 35,300 1,000 30,XD 3,i00 35700 C FN 1415 _ y M1t,Nztl Wa NIu1311 lex SSSS C Nma•a�w Logo" r�^awmsro�x ��M1A9Me�iG1a y MehttMnre CcSen E 2,000 20,]fID — AW Ee 3V LL Coaen QfF1'.IF' 9 ],i00 15,]00 9 1.300 Ig700 W 5.00 0 0 I 7 CENTRAL SAN CENTRAL SAN'S PAST EFFORTS ON SOLAR ENERGY Participated in the Regional Renewable Energy Procurement (R-REP) Led by Alameda County Process was initiated in 2012 Central San's Board approved entering into the R-REP memorandum of understanding in January 2013 Initial procurement was for consultants who could perform solar energy analysis Optony evaluated HHW, CSO and Pumping Stations g July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 20 of 46 4 Page 6 of 14 01%li,' R�REP RC -al RC.-able F:nrr� procQrcmcai `r POWER THROUGH COLLABORATION The R-REP request for proposals (RFP) for solar array installation was issued in 2015 Options included direct purchase or power purchase agreement (PPA) Resulted in solar arrays being installed under PPAs at Central San's HHW Facility, CSO Building and CSO VMS CFNTRAI SAN1 SOLAR ARRAY AT HHW FACILITY Y iii.. h _ ti-• Miss - CFNTPAI SAN ii i I July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 21 of 46 5 Page 7 of 14 Via ' SOLAR ARRAYS AT - v . CSO w r� ' 11 WHY WERE CSO AND HHW SELECTED FOR SOLAR ENERGY USE AT CENTRAL SAN? They had good installation characteristics. Sun exposure, no shading issues, adequate space They were on grid power. They had power use patterns that made them attractive to solar investors. July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 22 of 46 6 Page 8 of 14 -- ✓JrJrfJJerJJius�i,� IIIIIrrrm' • �JJrf<J�/------------ Prepared y 01I11111d1 - SOLAR June 2019 Prepared For: Central Contra Costa Sanitary District a_ "_el 1P 11ill h. (arc 13 Outline of Presentation z • Review site considerations and potential solar locations o • Discuss solar interconnection methods • Recommended pathway for Central San b Review risks related to implementation • Discuss next steps July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 23 of 46 7 Page 9 of 14 Available Areas for Solar Systems U„ 0 • With Staff,ARC reviewed the available locations on or D around the main treatment plant facility to identify locations that would be appropriate for solar • Three areas were identified as potential sites .�;?" ,T 1. Lagiss Property on Blum Road K • Largest area identified > • Some concerns for neighbor sight-lines y • Will require new electric services for any systems `^ installed • Difficult topography • Identified as most promising site 2. Marsh area adjacent to PG&E transmission lines • Long narrow unused land area • Shading concerns from power lines • CEQA concerns with proximity to marsh • Ultimately eliminated from consideration 3. Roof-top of 4737 Imhoff Place • Flat roof area that would be good for a small easily-installed roof-top system • Eliminated as considered "last resort"option due to size 1s Primary Area of Focus—Lagiss Property on Blum Road 0 r • Provides the clearest opportunity for a large solar system to offset the most District costs D z • Can fit roughly 5.5MW of power, much more that the District will need M • Will need to go through CEQA K process � D • Does have potential N neighborhood concerns that will need outreach The layout shown attempts to screen the system behind the hill on the property 16 July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 24 of 46 8 Page 10 of 14 Net Energy Metering Aggregation vs Renewable Energy Bill Credit Transfer z M M Net Energy Metering Aggregation (NEM-A) r) • Allows for meters on the same property or adjacent properties to benefit from a single Z solar system utilizing full retail credit rates n • Accounting happens on a kilowatt-hour basis i • System sizing is limited to 100% of the energy use of the aggregated meters • Can utilize rate switching on benefitting accounts to maximize solar benefit E M 2 • Renewable Energy Bill Credit Transfer (RES-BCT) o • Program available to only public agencies V) • Has limited subscription capacity(-105 MW) o • Allows for a single solar system to offset costs of up to 50 other meters within the same o, county Z • Accounting happens on a dollar basis T • Benefits from the generating meter are limited to the generation component of the benefitting accounts • System sizing is limited to the generation component of a bill (-50% of total) 17 Renewable Energy Bill Credit Transfer Program Subscription Limit z • A Primary risk for the RES-BCT pathway is the customer subscription limit The program has a total subscription capacity of 105 MW o • As of May 31, 2019 the program had -20 MW of unallocated capacity and -43 MW of Z M pending capacity • Of the 43 MW of pending capacity, 2 MW are new applications and the remainder are z further along in the process. • Capacity becomes secured once a system has a signed interconnection agreement and a M approved building plans. o Ln0 RES-BCT Program Summary,Effective as of May 31,2019(Total cap of 105.25) Z 0 W M Z T_ Number of MW 41.43MW(39.36%of cap) 43.46MW(41.29%of cap) 2 .36MW(19.35%of ca ) ■Total Counted Towards Cap[6] []Total Pending Projects[5] ❑Total Unallocated Program Space(Estimated) 1s July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 25 of 46 9 Page 11 of 14 Interconnection Scenarios Considered z M • Scenario 1: Large NEM-A System • Install a 1.4 MW system the benefits all of the meters adjacent to the Lagiss Property o • Utilizes NEM-A interconnection method z • Limits the benefit of the solar system to offsetting the main plant facility and the other r) relatively small adjacent utility meters o • Will required a new service to be installed at the property for the solar generating Z account M • Scenario 2: Large RES-BCT System o • Install a 3 MW system that benefits all of the major pump stations in addition to the o main plant z • Utilizes RES-BCT interconnection method • Expands the benefits of the solar system District wide z • Will required a new service to be installed at the property for the solar generating T account • Scenario 3: Combination of Scenarios 1 and 2 • Install a 1.4 MW NEM-A system and a 1.7 MW RES-BCT system • Utilizes both interconnection methods • Will require two new services, potentially cost-prohibitive 19 Scenario Implementation Risks — Z M ComponentProject n O Z Z Implementation Complexity0 n 0 0 0 Z Interconnection Method O • m 2 O Neighborhood View O • Ln D Z • O Z Future Flexibility CO Z T_ CEQA Project Cost O O Higher Risk O Lower Risk 20 July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 26 of 46 10 Page 12 of 14 Scenario Financial Benefits z M M Total 25 Year First Year System Size Benefit n per Scenario GenerationGeneration Z InstalledCredit(25 years) PPA Rate Credit Rate Z M Scenario 1 1.4 $5,295,956 $3.78 $0.0992 $0.0648 0 Scenario 2 3.0 $14,983,222 $4.99 $0.1259 $0.0814 Z Scenario 3 3.1 $13,555,204 $4.37 $0.1139 $0.0739 M • Recommend Pursuing Scenario 2 as it provides the most benefit per watt installed o • Contrary to initial expectations,the RES-BCT approach is more beneficial than NEM-A z • The main plant's rate structure limits its benefit under NEM-A benefit structure o • RES-BCT allows more flexibility around which rate is used to generate benefit while m° continuing site operations on an independent rate structures m • The breakeven PPA rate indicates the rate at which the project has a positive life-cycle net benefit • The first year generation credit rate indicates the rate at which the project is projected to be cash positive starting from year 1 21 Recommended Approach and Net Benefit — Z • Pursue Scenario 2 for 3 MW ground-mount system with Scenario 1 as an alternative if the RES-BCT program becomes oversubscribed o Z • Targeted PPA cost for the system would be below $0.09 per kilowatt-hour for 25 year Z M agreement • The forecasted cumulative benefit is shown below. °z • 3% utility escalation is used in the financial model. M 2 Scenario 2 Cumulative Savings O $4,500,000 a, N $4,040,974 $4,000,000 D v ' Z $3,S0o,000 v W $3,000,000 ? m .o T $2,500,000 o T_ L $2,000.000 $1,500,000 N $1,000,000 $500,000 V $0 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 ($500,000) . 22 July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 27 of 46 11 Page 13 of 14 Scenario 2 3 MW Solar System Size for Reference on Lagiss property z T M m Z n m x ■ ■■- NEXT STEPS FOR SOLAR ENERGY Confirm implementation approach Begin community outreach Begin environmental review (CEQA) ; Develop RFP 8 : As,' ;■ Receive and evaluate proposals Determine whether or not to proceed with a project --° fi I. CENTRALSAN July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 28 of 46 12 Page 14 of 14 QUESTIONS CFNTRAI SAN July 22, 2019 Special REEP Committee Meeting Agenda Packet- Page 29 of 46 13