Solar on Multifamily Affordable Housing (SOMAH)

Solar on Multifamily Affordable Housing (SOMAH) program provides incentives for solar energy photovoltaic systems for multifamily affordable housing. Those interested in learning more about the SOMAH Program should visit the program's website:

Key Components of the SOMAH Program:

  • A budget up to $100 Million annually, collected through June 2026, from the electric IOUs' Greenhouse Gas Auction Proceeds for this solar program
  • Incentive levels for customers go up to $3.50 per AC Watt for load serving tenants and $1.19 per AC Watt for load serving common areas (as of March 16, 2023) and are dependent on tax credit usage for the project
  • Encourages solar system installations in California's disadvantaged communities across the state
  • Emphasizing the explicit goal that incented solar systems lower tenant energy bills
  • Develop by December 31, 2032, at least 300 megawatts of installed solar generating capacity

Implementation of SOMAH

Assembly Bill (AB) 693 (Eggman, Chapter 582, 2015) provides financial incentives for the installation of solar energy photovoltaic systems on multifamily affordable housing properties throughout California.  The statute, among other things, prescribes criteria for participation in the incentive program; sets targets for installation of solar PV systems; identifies various required elements for the Program; and gives direction to the California Public Utilities Commission (CPUC) on the program administration.

In response to the legislation, the CPUC, in proceeding R.14-07-002, issued a Ruling to stakeholders seeking input on the design, implementation, eligibility and other programmatic issues for the new program.  Nearly 25 parties provided over a thousand pages of comments in response to the ruling.

In December 2017, the CPUC issued a decision, D.17-12-022, which outlines the program design for the SOMAH Program to incentivize solar systems. The Decision builds on many of the program successes and lessons learned from the California Solar Initiative Multifamily Affordable Solar Housing Program, which ends in 2021. Pursuant to this Decision, the utilities also created the SOMAH virtual net energy metering (VNEM) tariff. Virtual net energy metering allows the credit from an eligible renewable generator to be shared between multiple benefitting accounts. A property owner assigns benefits (from the renewable generator or generators) to a property's common area and tenant accounts. Solar credits show on customer bills as energy offsets (kWh) and receive export credit compensation ($/kWh) from the utility when there are net exports in a given time period. Learn more about net energy metering here

In March 2018, the CPUC's Energy Division selected via a competitive bidding process, a single, statewide program administrator team. The SOMAH Program Administrative team is comprised entirely of non-profit organizations: the Center for Sustainable Energy (CSE), GRID Alternatives (GRID), the Association for Energy Affordability (AEA), and the California Housing Partnership Corporation (CHPC). On July 1, 2019, SOMAH began accepting applications.

Incentive levels for program applicants range up to $3.50 per AC Watt for renewable capacity serving tenants and $1.19 per AC Watt for renewable capacity serving common areas. The incentive levels are dependent on tax credit usage for the project and expected performance of the eligible renewable generator(s). The program also has a mandate that incented renewable energy generation systems lower tenant energy bills through the SOMAH virtual net energy metering tariff. The SOMAH program encourages solar system installations in California's disadvantaged communities (DAC) as defined by CalEPA pursuant to Health and Safety Code Section 39711. For the SOMAH program, this is defined as DACs that score in the top 25 percent of census tracts statewide in the CalEnviroScreen tool from either the current or previous version. It also includes the 22 census tracts that are in the highest 5% of the CalEnviroScreen’s Pollution Burden.

In 2023, the Legislature passed Senate Bill 355 (Eggman, 2023) to adjust and expand the SOMAH eligibility criteria and extended the program through 2032. The new legislation also permits that if residential properties are new construction, then incentives can be used for the portion of a system that goes beyond building energy code requirements. It also permitted the Commission to consider authorizing advance payment loans as part of SOMAH, so long as the program can secure evidence that the project could not occur without an advance payment. The legislation went into effect on January 1, 2024.


Applying for SOMAH Program Incentives

For information on how to apply for incentives in your area, please go the SOMAH Program website and select your utility provider under “Ready To Apply”:

To be eligible, at a minimum, your property must:

  • Be deed-restricted, low-income residential rental housing (including mobile home parks),
  • Have at least five rental units,
  • All units must be individually metered,
  • Be an existing property, except new construction may be eligible if exceeding energy code requirements,
  • Be a utility or community choice aggregator (CCA) customer in the following utility territories: Pacific Gas & Electric, Southern California Edison, San Diego Gas & Electric, Liberty Utilities or PacifiCorp, and
  • Satisfy one of the following: 
    • 1) 66% of the property residents have incomes at or below 80% of the area median income or
    • 2) property is in a defined disadvantaged community (DAC) or
    • 3) property is owned by a California Native Tribe or
    • 4) property is owned by a Public Housing Authority or Public Housing Agency 

Solar on Multifamily Affordable Housing (SOMAH) - You Tube video

Recent News for SOMAH

  • Decision 23-11-068 continued the SOMAH virtual net energy metering (VNEM) tariff for program participants along with some essential modifications.
  • Senate Bill 355 (2023, Eggman) enacted changes to the SOMAH program, primarily extending its term and expanding eligibility criteria.
  • SOMAH incentive levels have been raised up to $3.50/watt for tenant areas and $1.19/watt for common areas and the incentive step-down has been ended (D.23-03-007 Amending D.17-12-022).

Upcoming Events for SOMAH Proceedings and Reports 

  • On May 5, 2023, the Commission issued a ruling as part of Rulemaking (R.) 14-07-002 asking for input on the SOMAH program. Opening comments are due on June 2, 2023, and reply comments due on June 16, 2023.
  • The SOMAH virtual net energy metering tariff is part of Rulemaking (R.) 20-08-020. Visit NEM Revisit ( to learn more about this ongoing proceeding.
  • SOMAH program event information can be found here:


SOMAH Information & Reports

Click on the link to go to the relevant page or section below.

 SOMAH Regulatory Proceeding Information

 SOMAH Program Information
 SOMAH Decisions, Rulings, and Advice Letters   SOMAH Program Website
 Net Energy Metering (NEM) Information  SOMAH Program Handbook
   SOMAH Program Semi-Annual Reports 
  SOMAH Joint-IOU Semi-Annual Reports
  SOMAH Evaluation Reports 
SOMAH Decisions, Rulings, and Advice Letters

The CPUC Rulemaking R.14-07-002 currently handles all issues related to the SOMAH Program.  Decisions and regulatory matters include:

  • Decision D.17-12-022 (December 2017) establishes the SOMAH program
  • Resolution E-4987 (April 2019) approves with modifications the SOMAH Program Handbook Program Implementation Plan in Compliance with Decision (D.)17-12-022. Adopted Program Implementation Plan (CSE 92-E-A/GRID 12-E-A) and Program Handbook (GRID 11-E-B). The Program Handbook has been updated since this initial filing.
  • Advice Letter 3285-E Disposition (April 2019). Disposes of San Diego Gas and Electric's advice letter that provides information regarding establishment of a Solar on Multifamily Affordable Housing Balancing Account (SOMAHBA) pursuant to D.17-12-022.
  • Decision D.19-03-015 (April 2019) modifies D.17-12-022 providing flexibility in IOU administrative expenditures. It also outlines options regarding auditing or review of the SOMAH program and establishes co-funding and incentive agreement deadlines.
  • Decision D.20-04-012 (April 2020). The decision determines revenues are available and that there is adequate participation and interest in SOMAH program, continuing authorization of allocation of funds to the SOMAH program through June 30, 2026.
  • Resolution E-5054 (June 2020) The Resolution approves revisions to the SOMAH Program Handbook to limit participation of a photovoltaic (PV) project to either the SOMAH Program or the MASH Program.
  • Disposition of CSE Advice Letter 133-E/133-E-A (April 2022) which approves SOMAH Program Handbook 5th Addition.
  • Decision (D.) 22-09-009 amended D.17-12-022 SOMAH forecast budgeting process the IOUs can propose to set aside their proportionate share of $100 million for SOMAH, if they adequately show that the IOUs' collective revenue will exceed $1 billion. 
  • CSE AL 138-E-A was approved on March 6, 2023 (Energy Division Disposition Letter). CSE Advice Letter 138-E to update the SOMAH Handbook was submitted on September 29, 2022, with substitute sheets provided on November 9, 2022, and December 14, 2022. A supplement 138-E-A was submitted on February 10, 2023. 
  • Decision (D.) 23-03-007 amended D.17-12-022 incentive levels to raise the highest incentive level possible to $3.50/watt for tenant areas and $1.19/watt for common areas and ends the annual incentive step-down.
  • CSE AL 141-E (with substitute sheets from 5/15 and 5/31) was approved on June 12, 2023 (Energy Division Disposition Letter). It amends the Program Implementation Plan and Handbook in compliance with D.23-03-007.
  • Decision (D.) 23-11-068 continued the SOMAH virtual net energy metering (VNEM) tariff for program participants along with some essential modifications.
  • CSE AL 147-E was submitted on 1/5/24 requesting to revise the Program Implementation Plan and Program Handbook to implement Senate Bill 355 (Eggman, 2023).

If you wish to receive notice of proceeding information the public can join the proceeding as “information only,” follow the instructions here.


IOU SOMAH Semi-Annual Administrative Expense Reports

Pursuant to D.19-03-015, the electric IOUs must jointly file and serve semi-annual reports detailing their administrative expenses incurred in support of the SOMAH Program for the preceding six full months and show cumulative totals. The revised Excel template (as of December 2021) for the IOUs is here.

  • January 21, 204 Joint IOU Report (PDF, Excel)
  • July 21, 2023 Joint IOU Report (PDFExcel)
  • January 21, 2023 Joint IOU Report (PDF, Excel)
  • July 21, 2022 Joint IOU Report  (PDF, Excel)
  • January 21, 2022 AMENDED Joint IOU Report (PDF, Excel)
  • July 21, 2021 Joint IOU Report (PDF, Excel)
  • January 21, 2021 AMENDED Joint IOU Report (PDF, Excel)
  • July 21, 2020 Joint IOU Report (PDF, Excel)
  • January 21, 2020 Joint IOU Report (PDF, Excel)
  • July 21, 2019 Joint IOU Report (PDF, Excel
SOMAH Program Semi-Annual Progress and Expense Reports

Pursuant to Appendix B of D.17-12-022 the Program Administrator submits semi-annual reports to the Director of the Energy Division on progress of the SOMAH program. These reports are also available on California Distributed Generation Statistics.

  • January 1, 2024 Program Administrator Report (PDF, Excel)
  • July 30, 2023 Program Administrator Report (PDF, Excel)
  • January 1, 2023 Program Administrator Report (PDF, Excel)
  • July 30, 2022 Program Administrator Report (PDF, Excel)
  • January 31, 2022 Program Administrator Report (PDF, Excel)
  • July 30, 2021 Program Administrator Report (PDF, Excel)
  • January 1, 2021 Program Administrator Report (PDF, Excel)
  • July 30, 2020 Program Administrator Report (PDF)
  • January 1, 2020 Program Administrator Report (PDF)

The most recent SOMAH Program Semi-Annual Expense Reports can also be downloaded on DG Stats here.


SOMAH Evaluation Reports

Pursuant to AB 693, D.17-12-022 and PU Code 2870(j)(1) and PU Code 913.8, Energy Division is directed to provide regular evaluations to the legislature of the SOMAH Program.

Evaluation reports:

Evaluation webinar slides:


Beyond SOMAH, and other utility programs, these agencies also provide support to affordable multifamily properties:

California Tax Credit Allocation Committee (TCAC) CTCAC

California Housing Tax Credit Financing Agency Multifamily Programs | CalHFA

California Department of Housing and Community Development Multifamily Housing Program (MHP) | California Department of Housing and Community Development