California reduced economywide greenhouse gas emissions by 22% in the 16 years after the state passed its landmark climate law in 2006, according to the latest California Green Innovation Index.
The state reduced its total carbon dioxide equivalent output by 2.4% between 2021 and 2022, according to an annual report card by the self-described nonpartisan climate and budget-focused think tank Next 10. The report examined data through 2022.
The transportation sector, accounting for 38% of California emissions, drove the year-over-year decrease in 2022 with a drop of 3.6%. Emissions from heavy-duty vehicles fell 13.1%, while light-duty vehicles saw a 2.4% drop.
"This is really a big deal for California because you've seen all the cars we have," Next 10's founder Noel Perry said in an interview. "We hope those numbers will continue because that will be a large determinant of whether we can hit our 2030 goal."
While more analysis is needed, Perry said California's ambitious clean car standards likely contributed to the drop in transportation emissions.
The pace of emissions reductions is accelerating, the index showed, but it still is not fast enough for the state to meet its 2030 climate target.
To reach its goal of a 40% reduction from 1990 levels by 2030, the index shows that the state now needs to achieve a 4.2% emissions cut annually. At the current rate, California would meet the 2030 goal in 2037, Perry said.
Power sector showed mixed results
Unlike transportation, the power sector had some mixed results, according to the index.
Summer heat waves and a higher reliance on natural gas-powered power plants in recent years amid reliability concerns likely contributed to a 9.5% increase in in-state power emissions from 2019 to 2022, Stephanie Leonard, Next10's research director, said in an email. Between 2021 and 2022, however, electricity-related emissions fell 4.3%.
Because California's power sector has already decarbonized much of its operations, Leonard said achieving further emission cuts will be difficult.
The index shows that all new power plant capacity the state added since 2021 consisted of renewable resources, but clean energy resource additions have slowed. Renewable energy generation accounted for nearly 37% of the state's power mix in 2023, up 1.1% from 2022.
"All in all I think we're going in the right direction," Perry said. "But we still have to reduce emissions by about double of what we've been doing and that really spells a challenge for us."
Retaining a US Environmental Protection Agency waiver that allows California to set stricter tailpipe emission standards than what the federal government requires will be critical, Perry said. During his first term as president, Donald Trump revoked that waiver, and he is expected to do so again.
The Next 10 report suggested that power bills, a sore topic in California, may be largely offset by energy conservation policies. While electricity rates are creeping up, California's energy efficiency investments are keeping residential electricity largely in line with the national average, the data showed. In 2022, residential customers paid on average 2% more than the nation as a whole, it found.