Additional Solar Needed to Offset Electrification Costs for Multifamily Apartments in Southern California Edison Territory

Study Question:
What amount of additional solar is required to make utility bills of an all-electric apartment
building cheaper than its gas hybrid counterpart, built to the 2019 California Title 24 New
Construction Low Rise Residential Multifamily Energy Code in all Southern California Edison
Territory Climate Zones?

Summary of Study:
Three scenarios were studied using a two-story multifamily project, all designed to meet
California’s 2019 Title 24 Code with minimum code compliant PV arrays.
The scenarios studied are as follows:

1. Minimum prescriptive compliance options for all-electric and gas-hybrid construction
2. High performance mechanical system options for all-electric and gas-hybrid construction
3. Adding more PV to the all-electric Minimum Prescriptive and High-Performance options
   until the utility bills are lower than the gas-hybrid options

The two-story multifamily project of study consists of 26 residential apartments (Figure 1) and
was modeled using Energy Pro v8.0.3. The building of study was modeled in Southern
California Edison (SCE) Territories 5, 9, 10, 13, 14 and 16 residing in California Energy
Commission (CEC) Climate Zones 6, 9, 10, 13, 14 and 16 respectively.

Figure 1: The apartment building of study, modeled in all Southern California Edison Territories

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