What percentage of California’s power is solar?

Two percentages, and why both are right

You will see two different shares quoted for the same year, and the difference is what each one measures. The CEC’s Total System Electric Generation report puts 2024 total system power at 278,338 gigawatt-hours, a total that includes electricity imported from other states. Solar made up 21.30% of that system total, counting solar power imported into California as well as solar made here. Looking only inside the state, California solar plants produced 50,666 gigawatt-hours, or 23.44% of in-state generation (CEC, checked September 23, 2026). The first number describes the power Californians used; the second describes what the state’s own plants produced.

Rooftop solar is counted separately

Home and business rooftop systems sit behind the customer’s meter. The power they make is used on site first, so it never shows up as utility generation. The CEC’s solar statistics page puts it simply: most electricity from PV “is not counted into the total electricity production of the utility companies” because the panels are on individual homes and businesses (CEC, checked September 23, 2026).

Instead, the CEC reports its effect on demand. In the 2024 report it states that more than 17,400 megawatts of behind-the-meter solar capacity “has displaced approximately 10 percent of energy supplied by local utilities.” Adding that to the 21.30% plant share gives a rough sense of solar’s full footprint, but the two numbers are measured differently, so treat any combined figure as an estimate, not a CEC statistic.

How many California homes have solar?

The CEC pages above do not publish a household count. The best public tally is California Distributed Generation Statistics, which the CPUC oversees. It covers every solar system interconnected under the net metering tariffs of PG&E, SCE and SDG&E and updates its interconnection data monthly, usually with about a six-week delay (DGStats FAQ, checked September 23, 2026). Two limits matter. It counts projects, which include businesses, not just homes, and it leaves out customers of municipal utilities such as LADWP and SMUD.

How solar’s share has grown

The CEC’s plant table tracks solar PV plants of one megawatt and larger. It excludes residential rooftop systems, backup generators and imports, and was last updated June 16, 2026 (CEC, checked September 23, 2026).

Over those four years, plant capacity rose by roughly 59% and generation by about 60%. For a longer view, the CEC notes that in 2012 solar PV produced 1,025 gigawatt-hours, the first year it passed solar thermal plants. The CEC’s plant table and its Total System Electric Generation report are compiled differently, so their 2024 solar totals do not match exactly; use one series at a time when you compare years.

What a solar-heavy grid means for your bill

When a large share of the state’s power arrives in the middle of the day, midday electricity becomes less valuable and evening electricity more so. On sunny spring and fall days the grid can have more renewable power than it can use, which is why midday solar gets curtailed (the duck curve). That pattern is behind the CPUC’s Net Billing Tariff. For PG&E, SCE and SDG&E customers who applied to connect since April 15, 2023, exported solar is credited at values from the CPUC’s Avoided Cost Calculator, which are usually lower than the price of power you import (CPUC, checked September 23, 2026). The result is that new systems are designed to use more of their own output, and many add a battery to carry midday energy into the evening.

Those trade-offs are covered in the guide to home solar in California, the comparison of NEM 2.0 and net billing and the battery payback analysis. If you are weighing a system of your own, start with the pros and cons of solar in California and then the guide to choosing an installer.