Climate Science and Policy

The State of California is working to bolster local electricity resilience by accelerating the adoption of microgrids, notably through its Microgrid Incentive Program (MIP). This Program allocates the State’s three largest electric utilities $200 million to build community microgrids that support disadvantaged communities, specifically in fire and outage prone areas of their service territories.

This work presents a new tool built to analyze microgrid suitability in the service territories of these utilities. It then applies this tool in a study that locates areas potentially eligible for California’s new MIP and maps optimal sites for microgrids under MIP objectives as well as a range of other grid modernization goals. It identifies and ranks where microgrids could be most beneficial by seeding an ArcGIS suitability model with criteria chosen by the utilities and informed by the California Public Utilities Commission, California’s Office of Planning and Research, and MIP workshop participants. These criteria reflect utility efforts to bolster resilience for key populations in areas vulnerable to disruption and include Tier 2 and 3 High Fire Threat Districts, locations of previous Public Safety Power Shutoffs, circuits with historically low levels of reliability, and disadvantaged / vulnerable populations. Other criteria speak to additional benefits that microgrids can provide, such as reducing pollution, arbitraging locational marginal electricity prices, and integrating renewable energy.

Results indicate that 70% of incorporated and census designated places within the three utilities’ service territories likely have at least one location that’s eligible for MIP funds. Historically marginalized communities are the most likely to lack the capital, technical/regulatory expertise, and institutional support required to pursue this funding. As such, this result indicates that capacity building in these communities to develop the skills and resources necessary to undertake adaptation projects may be necessary to reach the Program’s equity goals.

Modeling suitability under different secondary goals, in which various aims beyond resilience are weighted and scored, changes the distribution of the most suitable locations—with the percentage of individual places featuring high suitability scores ranging from 6% to 26% for different portfolios of benefits. In some areas, three goals are often aligned (those of lowering pollution, improving equity, and achieving incremental decarbonization). This suggests that realizing multiple microgrid co-benefits is feasible, but that doing so marks a distinctly different approach from the current focus on wildfire resilience. Ultimately, policy choices that prioritize different sets of microgrid goals in different locations—depending on the unique burdens and threats facing local communities—and shift power from utilities to communities may offer the most viable path forward to realizing potential co-benefits.