Renewable Energy & Storage

How Are We Doing?

Renewable energy and storage received a thumbs up because of increased distributed solar photovoltaics (PV) and increased uptake of energy storage, a vital component of the transition to a clean but intermittent renewable energy-sourced economy. 

In 2019, San Diego County saw its highest single year increase of new solar installations and capacity, reaching a cumulative of 1.2 gigawatts distributed solar installation, the highest among California counties. In addition, renewables on the grid as a percentage of San Diego Gas & Electric (SDG&E) electricity mix was 43% in 2018, leading California investor owned utilities. Solar and wind energy make up most of SDG&E’s renewable energy mix.

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thumbs up

Improved more than 1 percent from 2018 to 2019

In September 2018, California adopted SB100, the 100 Percent Clean Energy Act of 2018, that increases the current mandated renewables portfolio standard (RPS) from 50% renewables to 60% renewables by 2030 and establishes state policy of 100% zero-carbon electricity by 2045.

All three investor owned utilities (IOUs) in California, including SDG&E, exceeded the 2020 target of 33% renewable a few years early. SDG&E has achieved the highest percentage of renewable energy (44% of sales) in its electricity portfolio, among IOUs, however, the other two IOUs are catching up. Apart from the default electricity portfolio offered to customers, all IOUs have programs where customers can select higher renewables at a premium cost. SDG&E’s EcoChoice program for example allows customers to select up to 100% of electricity from renewable sources.

Since 2016, SDG&E’s renewable electricity mix has been based on large-scale utility solar and wind energy with a small portion that includes hydro, landfill gas and biomass. Small-scale distributed solar does not count towards IOU’s renewable energy portfolio, but adds to the utility’s renewable capacity of 1.9 GW.

Since 2016, SDG&E’s renewable electricity mix has been based on large-scale utility solar and wind energy with a small portion that includes hydro, landfill gas and biomass. Small-scale distributed solar does not count towards IOU’s renewable energy portfolio, but adds to the utility’s renewable capacity of 1.9 GW.

In the SDG&E service area, which includes San Diego County and a small portion of Orange County, over 30,000 of new solar PV systems were installed in 2019, an increase of 30% from 2018 and a total through 2019 of more than 170,000 systems. All the new systems added 230 MWs of solar capacity and brought the total distributed solar capacity to over 1.2 GW. Both the number of new installations and the new capacity added are the largest single-year increases the SDG&E service area has ever seen. The majority of the new installations and new capacity in 2018, 99% and 84% respectively, were from residential rooftop solar systems. In 2019, the City of San Diego was ranked among the top major cities in the nation in both the number of solar systems installed per resident and total solar capacity.

San Diego County had the highest total solar capacity among counties in California with over 1.2 GW installed through the end of 2019. Due to the intermittent nature of solar (and wind) generated electricity, storage of the excess electricity produced by these resources is vital to the success of renewables penetration needed for the transformation to a low carbon economy. Investor owned utilities have a target of more than 1.3 MW storage to be online by 2024, of which SDG&E’s share is 165 MW. 

The California Public Utilities Commission's Self-Generation Incentive Program (SGIP), one of the most successful distributed generation incentive programs in the country since 2001, was modified over the years to complement the transition to a low carbon economy and incentivize distributed energy resources, including energy storage, that contribute to greenhouse gas reduction goals. In 2017, about 80% of the SGIP incentive funding was allocated to energy storage which is based on several factors, including the kilowatt-hour (kWh) capacity of the system.

This chart shows the number of incentive applications through the Self-Generation Incentive Program (SGIP). SGIP has been helping California lead the nation in residential battery storage deployment by providing an upfront rebate based on the amount of energy stored in the battery. The significant increase in the number of applications during 2017–2018 was due to an increase in residential battery storage, especially storage coupled with on-site solar systems. The increase of residential battery storage applications leveled off in 2019, however, still represented 98% of total applications and over 60% of the power. 

Why is Renewable Energy & Storage Important?

High quality of life means the region boasts a thriving economy, a healthy environment, and is an equitable place for all San Diegans to grow and prosper.

  • Environment: Renewable energy is important in reducing greenhouse gas emissions and improving air quality. When coupled with energy storage, renewable sources provide a continuous energy supply, increasing system reliability and cost-effectiveness.
  • Economy: The analysis of California’s new residential solar PV mandates shows it will save families thousands of dollars over the first decade of ownership. The reduction in energy bills due to the solar PV system exceeds the corresponding increase in mortgage payment, by around $35 per month on average.
  • Equity: Distributed generation, small-scale renewable technologies that produce electricity close to the end user, makes the region more resilient to power outages. Power outages, including the prevalence of Public Safety Power Shutoffs (PSPS) during the 2019 wildfire season throughout the state, led to 60% of the new expanded Self Generation Incentive Program being dedicated to “Equity Resiliency” projects for low-income customers, those who live in high fire risk area, those who experienced PSPS events on two or more distinct occasions, and critical facilities that provide services to these affected areas. These incentives are expected to cover the entire installed cost of any residential energy storage system available.

Regional Response


In the San Diego region nearly all recent Climate Action Plans have measures mandating photovoltaic (PV) systems that are additional to state policies promoting distributed generation. This demonstrates availability of increased capacity for distributed generation and potential for more local generation.


The most recent major regional response to accelerating renewables use for electricity generation comes from the development of community choice energy aggregation (CCA) programs which are locally run with typically higher renewables targets than the state mandated targets for utilities. The San Diego region has one established CCA since 2018, and two more (Clean Energy Alliance which covers 3 cities, and San Diego Community Power which covers 5 cities) will come online in 2021.


Partnerships have developed among cities to study the feasibility of and adopt agreements to provide community choice energy. San Diego, La Mesa, Chula Vista, Encinitas and Imperial Beach joined forces and Carlsbad, Del Mar and Solana Beach are doing the same.

What Are We Measuring?

We measure renewable energy by tracking the number and capacity of new solar installations and the increase in incentivized energy storage projects in the SDG&E service territory. We also track the historical trend of renewable energy as a percentage of SDG&E sales and the distribution of renewable energy procurement by type. Learn more about the data.