San Diego County Regional Decarbonization Framework

University of California San Diego
Project Completed March 2022

Working with the University of California San Diego, Synapse led the development of the building decarbonization portion of the San Diego County Regional Decarbonization Framework. Our analysis began with a detailed assessment of the current state of the buildings in the county and the associated direct emissions by building location and type, as well as by end use. We described and evaluated decarbonization options including electrification of space and water heating, cooking, and laundry, as well as the potential for low-carbon combustion fuels, and projected cost and performance of each option. We then utilized regional decarbonization pathways developed by Evolved Energy Research as the foundation to establish detailed projections for the stock and energy use of different end uses across the county, showing the transition from combustion fuels to electricity.

We quantified the capital and operating costs for each pathway, and showed that three approaches (a central high-electrification case; a higher-efficiency case; and a delayed electrification case dependent on low-carbon fuels) all have comparable estimated costs, although their risks are quite different. We concluded our contribution with a detailed analysis of the impact of changes in pipeline gas consumption on natural gas rates. We evaluated the resulting risks to San Diego’s gas utility from its current business model and identified options for reducing those risks, including accelerated depreciation and minimizing unnecessary investment in gas utility assets.