Albert Lopez
Planning Director

Large Commercial Solar in Rural Alameda County

This page documents the 2021-2022 effort by the Planning Department to finalize a policy/ordinance related to Large Commercial Solar projects. Although this work began nearly a decade ago, the need to formalize the County's regulations for this land use type is timely given the continued interest in developing Large Commercial Solar in the rural portions of Alameda County, specifically the East County. The County has been largely receptive to developing renewables in East County with a long history of wind energy in the Altamont Pass Wind Resource Area (APWRA), and more recently has received interest from the renewable sector with projects in solar and battery storage. The County has to date not had policy or ordinances that govern solar or battery storage, and this page serves to provide general information to the public in the form of staff reports, staff analysis, least conflict mapping and background material that has been generated to assist the public as well as County decisionmakers as they consider a policy/ordinance direction.

Draft Solar Policies

The development of draft policies for Large Commercial Solar goes back a number of years and the archival information can be found here. Pertinent to the process currently underway, in 2017 Staff prepared a comprehensive draft policy matrix to address Large Commercial Solar in the rural East County; the draft policies are comprehensive and address multiple issues related to solar development, including where projects may be permitted, conservation of agricultural land and soils, Williamson Act land conservation contracts, mitigation of biological impacts, and reclamation/restoration of solar sites upon abandonment or termination of operations. These policies have been slightly modified since 2017, but substantially remain Staff's original recommendation.

The Board of Supervisors Transportation and Planning Committee has reviewed these policies on several occasions at public hearings in 2019, 2020 and 2021, but has heard much controversy regarding siting and size of solar projects. Consequently, the Board directed Staff to engage the public, through the Agricultural Advisory Committee (AAC), to craft an alternative set of solar policies that would reflect their values, concerns, and expectations. In 2021 staff presented draft policies to the County's Agricultural Advisory Committee (AAC) for their input. The AAC created a Solar Subcommittee which met several times in 2021, resulting in an AAC version of the policies that looked at several ways to regulate solar development, including limits or prohibitions on location, size and overall maximum allowable acres, underlying land use, preservation of agricultural and biological land functions, blending of solar to benefit agriculture (agrivoltaics) or biology / ecology.

The different versions of the policies can be found below, as well as a compare/contrast document that shows where more discussion and consensus is needed. The Planning Department is tasked with convening all the various stakeholders on this issue (beginning in late 2021 through 2022) to develop a final set of policies (and potential ordinances) that can be approved by the Board of Supervisors.

Compare and Contrast Policies

Compare and Contrast Policies with annotations

Ag Advisory Cmte definitions and solar policy matrix

2018 Solar Energy Policy Matrix

March 2022 Statement of Policy

Board of Supervisors Meeting April 14, 2022

Least Conflict Mapping

There has been general community consensus that in order to finalize any policies or ordinances related to Large Commercial Solar, that a mapping exercise is needed to show conflict areas such as environmentally sensitive areas, scenic corridors, important farmland/soils, Williamson Act parcels, and other areas of potential conflict. Draft maps covering these topic areas can be found below:

Map of Aspect degrees

Map of Conservation Lands Network

Map of Critical Habitat Endangered Species

Map of Slope

Map of Farmland Classification

Map of Parcels Williamson Act

Map of Stories Index Ag Soil Ratings

Map of Transmission Lines and Substations

Map of Vegetation Rarity


At the end of 2021 the Board of Supervisors considered an urgency ordinance (a moratorium) to specifically pause the approval of Large Commercial Solar projects in East County to allow time for the development of policies and ordinances to regulate these types of projects. The material presented to the Board can be found below. This page will be updated in early 2022 to reflect their decision in this matter.

UPDATE: At the 12/9/2021 Board of Supervisors meeting the draft moratorium found below was presented to the Board for their consideration. Ultimately the BOS did not support a moratorium and directed staff to continue to develop the policy matrix (found above), with a firm deadline of returning to the full Board by the end of March 2022. Staff will continue to convene meetings of the Solar Working Group and host larger community meetings in early 2022.

Nov 2021 TP memo on Large Commercial Solar battery and moratorium FINAL

Draft Solar Urgency Ordinance 11-2021 DRAFT

Board of Supervisors 12/9/2021 meeting materials

Community Meeting Information

The Planning Department will host a general community meeting on February 8th 6-9 PM to solicit input which will inform the final policy document presented to the Board of Supervisors. The agenda for the meeting can be found at the link below. This will be a Zoom meeting format.

Draft Agenda For Community Meeting

Community Meeting Presentation 2.8.2022

Solar Conflict Mapping

Video recording of Community Meeting 2.8.2022 (Zoom)

California Environmental Quality Act

Any policies/ordinances that result from the process described above would need further evaluation and public hearings as required by the California Environmental Quality Act (CEQA). The extent of the review has not yet been determined but will depend on the policies or ordinances themselves. The CEQA process is likely to take approximately 6 months; this webpage page will be updated as required to reflect current documentation and public hearing announcements.