Multifamily Affordable Solar Housing (MASH)

Program Overview

The Multifamily Affordable Solar Housing (MASH) program provides incentives to offset the costs of installing new solar energy systems on multifamily, affordable housing buildings in California. The program began on November 16, 2007, when the California Public Utilities Commission set aside $108 million for a multifamily, low-income incentive program within the larger California Solar Initiative Program.

The goals of the MASH program are to improve the quality of affordable housing, decrease energy use and costs for occupants and encourage the use of high-performance solar systems that are beneficial to California’s environment.

Who Benefits from the Program?

The MASH program applies to multifamily, affordable housing buildings with new solar-panel energy systems. Typically, it is the owner of the multifamily complex that applies for the incentive in order to offset the cost of installing a new solar energy system for common areas, as well as to reduce the monthly energy costs for low-income tenants.


The MASH program provides post-installation, fixed rebates, which are calculated based on the size and expected performance of the solar system installed. Your contractor can help you determine the size of the system you need and how to allocate percentages of the power generated by the system between common areas and tenant areas in order to maximize the benefits for both the building owner and low-income tenants.

Two incentive types
Common area load offset
$1.90 per/watt
Tenant area load offset
$2.80 per/watt

Your contractor will explain that the percentage allocated to the common area takes into account historic electricity usage, whereas the tenant percentages must be based on the square footage of the residential units. The higher tenant-incentive level encourages owners to allocate greater percentages to tenant areas in order to offset the tenants’ electricity bills.

Tenants are also eligible for PG&E’s Virtual Net Energy Metering (NEMVMASH) tariff. This program allows all tenants in an affordable housing complex to benefit from energy generation credits derived from the building’s solar system. If the building meter configuration qualifies, tenants in buildings participating in the MASH program will automatically be enrolled in this tariff, which does not change their existing rate schedule.

How to Apply

Your contractor will help with the entire application process from materials to applications to interconnection.

Applications must be submitted through PowerClerk, an online database.

Important Note: Current funding for MASH is exhausted. New funding has been allotted to the MASH program by Assembly Bill 217. Funds are expected to be available in the first half of 2015. The wait list for the MASH program is currently closed and is not accepting new applications at this time.

Apply now

Add your application to the MASH wait list.


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