Achieving 100 Percent Clean Electricity

California has established a target of 100 percent carbon-free electricity by 2045 and increased its renewable energy requirement to 60 percent by 2030. To reach these goals, the Union of Concerned Scientists proposes ten strategies: improving energy efficiency (especially during evening hours), diversifying renewable sources (wind, solar, geothermal, and low-carbon bioenergy), phasing out natural gas equitably, using renewables for grid reliability services, investing in multi-timescale energy storage, integrating western electricity markets, leveraging distributed energy resources, electrifying buildings and transport, shifting demand to match production, and developing a skilled workforce.

• California has set a legal target to reach 100 percent carbon-free electricity by 2045 and has increased the renewable energy requirement for utilities from 50 percent by 2030 to 60 percent.
• To lower the costs of the clean energy transition and reduce reliance on natural gas, California should prioritize energy efficiency investments that encourage savings during evening hours when renewable supplies are less abundant.
• A reliable and cost-effective grid requires a diverse portfolio of renewable technologies—including wind, solar, geothermal, and low-carbon bioenergy—sourced from both large- and small-scale facilities inside and outside the state.
• California must develop an orderly and equitable plan to phase down natural gas generation, which currently meets about one-third of the state's electricity needs, prioritizing reductions in communities most affected by air pollution and global warming.
• Renewable energy technologies like wind and solar can provide essential fast-responding grid (ancillary) services, reducing the traditional reliance on natural gas and large hydropower for grid stability.
• Investment in energy storage (batteries, pumped hydropower, and compressed air) should span various timescales—hours, days, and seasons—and be targeted at locations vulnerable to reliability challenges or where it can improve air quality in disadvantaged communities.
• Greater integration and coordination of electricity markets in the West can provide a wider pool of carbon-free generation and reduce the need to curtail renewable output by exporting excess energy.
• The state should electrify transportation (cars and trucks) and buildings (replacing natural gas furnaces and water heaters) while ensuring these investments are flexible to support the integration of renewables on the grid.
• Flexible demand strategies, such as smart appliances, time-varying electricity rates, and electric vehicle charging, can shift consumption to coincide with peak renewable production and reduce the need to ramp up natural gas plants.

APA

Union of Concerned Scientists (2018). Achieving 100 Percent Clean Electricity. https://www.ucs.org/sites/default/files/attach/2018/12/Strategies-for-Clean-Electricity-Policy-Brief.pdf

Chicago

Union of Concerned Scientists. Achieving 100 Percent Clean Electricity. 2018. https://www.ucs.org/sites/default/files/attach/2018/12/Strategies-for-Clean-Electricity-Policy-Brief.pdf.

Wikipedia

{{cite report |author=Union of Concerned Scientists |title=Achieving 100 Percent Clean Electricity |date=December 2018 |url=https://www.ucs.org/sites/default/files/attach/2018/12/Strategies-for-Clean-Electricity-Policy-Brief.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{unionofconcernedscientists2018achieving, author = {{Union of Concerned Scientists}}, title = {{Achieving 100 Percent Clean Electricity}}, institution = {Union of Concerned Scientists}, year = {2018}, month = dec, url = {https://www.ucs.org/sites/default/files/attach/2018/12/Strategies-for-Clean-Electricity-Policy-Brief.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }