3 charts showing where California’s energy actually comes from
San Onofre Nuclear Generating Station image by IllaZilla, CC BY-SA 4.0, via Wikimedia Commons
The other day I was driving past the now-closed San Onofre nuclear power plant in San Diego County and I thought “with all of this recent talk about energy generation needs, where does California’s energy actually come from?” I quickly found the answer on the California Energy Commission website, but the data tables were a little dense for my simple brain. Personally, I understand things better with visual-aids so I created some graphs in Canva to visualize the information. Below you’ll find these graphs and a few interesting points I noticed.
Chart 1: Where does California’s energy actually come from?
The below chart shows California’s total energy generation by source for the year 2023. This includes both in-state generation and imported energy.
Hydro increased from 10.4% in 2022 to 13.5% in 2023 due to near-record levels of rain and snow in 2023.
All of California’s nuclear energy is produced by a single nuclear plant named Diablo Canyon Power Plant which is operated by Pacific Gas & Electric. This single plant produces 9% of the energy for the entire state.
Natural gas is still by-far the largest source of power for Californians. In 2023 California generated 37% of its total energy from natural gas, down from a high of 44% in 2014. Total natural gas generation is expected to increase over the next decade as energy demand is increasing due to the rise of power-hungry data centers. While nuclear generation holds promise long-term, the cost-savings and reliability associated with natural gas generation makes it a likely beneficiary of the increased demand in the near-term.
California Total Energy Generation 2023
Chart 2: California’s recent energy trends
This chart shows California’s energy trends from 2009-2023. I omitted some of the smaller energy sources to make the information more legible.
Total energy consumption over the past decade actually decreased from 296,628 in 2009 to 281,140 in 2023. This trend is expected to reverse with energy demand expected to rise significantly over the next decade.
Solar has increased dramatically since 2009, but has recently tapered due to many factors, one of which is a lack of energy storage. During sunny days there is an excess of solar energy produced during off-peak hours. With nowhere to store that excess energy, the price per kWh can actually turn negative in some instances.
You can see in the chart when the San Onofre Nuclear Generating Station was closed in 2012, taking with it over 2MW of clean-energy generation capacity. In it’s heyday San Onofre was providing energy for roughly 20% of Southern California.
California Energy Generation Trends 2009-2023
Chart 3: In-State Generation vs Out-of-State Imports
The chart below compares in-state vs out-of-state energy sources for 2023.
California imports more electricity than any other state. As of 2023 California imports 23% of its total energy from other states. This is down from 33% in 2013.
California imports more wind power than it produces. This may be surprising to anyone who has witnessed the seemingly endless miles of wind turbines in the California desert.
Perhaps unsurprisingly, 94.8% of coal energy is imported from out-of-state.
California in-state generation vs out-of-state energy imports 2023
That’s all folks. It’ll be interesting to see what the next few years of energy production looks like in California as we’re in a time of unprecedented change to our grid and the demands placed upon it. The California Energy Commission releases new statistics every year around May for the previous year, so be sure to keep an eye out for those updated numbers.
