Dave Kesner’s household was the first on his hilly La Mesa street to install rooftop solar panels in 2000, when a massive electricity shortage caused blackouts and price spikes across California.
“Our utility rates virtually doubled very, very quickly. And I just thought, ‘This is not sustainable,’” Kesner said.
He was happy with his rooftop setup until it finally died last year. Contractors said it would’ve cost at least $5,000 to replace, which didn’t make financial sense now that Kesner and his wife were empty nesters.
He later learned about something called plug-in solar at a community forum. For under $2,000, Kesner bought a kit that’s cheaper, smaller and much easier to set up than his old rooftop array — with no electrician required.
“I got it delivered on a Friday afternoon, and by Saturday afternoon it was up on the roof, plugged in, making power,” he said.
Four 250-watt panels sit on top of Kesner’s garage. He didn’t need to drill into the roof. They plug directly into a regular wall outlet and generate more energy than 16 of his old rooftop panels — enough to turn Kesner into a small-scale solar evangelist with his friends and family.
“Love solar. I think it's a win-win environmentally, financially," he said. "Take a little bit of power away from local utilities. So I very much wanted to do that.”
Systems like Kesner’s, often called balcony solar, are poised to get much more popular across California.
Last month, state lawmakers passed legislation that would allow households to install plug-in setups without going through the potentially time-consuming and pricey interconnection application process currently required for all solar panel installations regardless of size. Instead, they’d file a registration form with their utility.
Balcony solar would be treated less like a rooftop solar construction project, and more like an appliance. Plug-in setups would be permitted up to 1,200 watts — enough to power a fridge or window air conditioner.
The bill is on Gov. Gavin Newsom’s desk and would take effect Jan. 1 if it becomes law.
Plug-in panels are gaining momentum nationally as incentives for rooftop set-ups fade. Congress cut a 30% federal tax credit for solar last year, and California’s current net metering rules provide households much less credit for excess electricity sold back to the grid.
Mike Ferry, with UC San Diego’s Center for Energy Research, said plug-in panels can empower households that may not have the capital or long-term stability to get rooftop panels — like renters.
“There's a whole segment of consumers, probably the majority, that haven't been able to participate in that,” he said.
San Diego County, Ferry said, is well-suited for plug-in solar, which has become more affordable in recent years. The region gets lots of sunlight and electricity bills are typically more than double the national average.
“If you can utilize that investment in a small balcony solar system to offset some of your highest cost electricity and save some money on your utility bill, then it's a really good fit,” he said.
Still, California’s balcony solar policy includes some compromises.
Several utilities opposed the legislation over concerns electricity could backfeed onto the grid if equipment is damaged or installed incorrectly.
“SDG&E supports customer adoption of solar and energy storage technologies and recognizes the important role these resources play in advancing California's clean energy future,” SDG&E spokesperson Anthony Wagner said in a statement after the bill passed. “Our priority is ensuring that any technology operating on or near the electric system meets strong safety standards that protect customers, line workers and the public.”
A flurry of states have passed balcony solar legislation since last year, inspired by a movement that began in Germany in the early 2020s.
California’s regulations aren’t quite as consumer-friendly as some of its peers, said Rupert Mayer. He co-founded the Bay Area nonprofit Bright Saver, which advocates for plug-in solar and sells kits at wholesale prices.
If California’s legislation becomes law, balcony set-ups would need to be certified under new national safety standards that could mean, above a certain wattage, a user may need to hire an electrician to connect their panels to a special wall outlet.
“But of course, that is not very conducive to adoption,” Mayer said. “As soon as you hire an electrician, you might spend more on the electrician work than on the solar panel.”
As technology and safety standards evolve, Mayer said California could end up looking more like Germany and other European countries where plug-in solar has taken off.
“You see solar on every shed, on every barn, on every house," he said. "Next to the freeway, next to the railroad tracks — it is amazing.”
Mayer compared the current U.S. balcony solar landscape to the first era of rooftop panels, when homeowner interest outpaced laws in many places. Back then, some referred to it as “guerilla solar.”
“So in my mind, we're almost in a solar guerrilla movement 2.0 now, 30 years later,” Mayer said. “Where again, early adoption will drive the legislation and the codemaking and establish this as a useful thing that everyone can benefit from.
That’s as long as balcony solar is accessible in California. The new state policy would sunset in 2030 as a safeguard against unintended consequences for the power grid.
Mayer thinks there will be enough demand to extend it, though. He said there’s currently a waitlist for Bright Saver kits, with three shipping containers scheduled to reach California in the coming weeks.
