Why plug-in solar kit prices may fall: Utah, Germany and SB 868

The short answer: Bright Saver, a nonprofit that sells plug-in kits, expects prices to fall as more states let small kits skip the utility's interconnection process, as Utah did in 2025. Germany shows what can happen when the rules are simple. The price forecasts below are Bright Saver's projections, not promises. Not financial advice.

What Utah changed

Utah's H.B. 340, in effect from May 7, 2025, created a new class of "portable solar generation devices": up to 1,200 W, plugged into a standard 120-volt outlet and certified by UL or an equivalent lab. These devices are exempt from interconnection requirements and from net metering. They must have a feature that stops them powering the building's wiring during an outage, and the utility can't require approval, fees or extra equipment.^[source]

Bright Saver reports that within months of the law passing, the full price of a kit in Utah fell by about 50%.^[source]

What backfeed-prevention hardware is

Bright Saver says that before laws like Utah's, the only plug-in kits widely sold in the U.S. came with backfeed-prevention hardware: meters in the home's breaker panel that match the kit's output to the home's use, so no power flows to the grid. It says this hardware needs an electrician to install, and that the rules behind it nearly double the cost of a system.^[source]

pv magazine's California guide says SB 868 also exempts qualifying kits from utility requirements for extra equipment.^[source]

Germany's balcony solar boom

• About 1 million registered systems by Jun 11, 2025, an estimate based on Germany's national register of power plants.^[source]
• Perhaps up to 4 million once unregistered systems are counted, according to research Bright Saver cites.^[source]
• Simpler rules. Germany raised its limit from 600 W to 800 W in 2024 and cut registration down to a short online form, Bright Saver says, and kit prices fell sharply as more people bought them.^[source]

What Bright Saver projects

If at least 5 states adopt rules like Utah's, Bright Saver projects that:^[source]

• kit prices fall to about $0.58 per watt by 2027;
• the national average payback falls to about 4 years by 2028 and 3 years by 2032;
• about 24 million households, or 60 million people, use plug-in solar by 2035.

These projections come from an organization that sells kits, and were made in October 2025, before California's law passed. By October 2026, pv magazine's California guide counted California as roughly the tenth state to allow plug-in solar,^[source] so the condition behind these projections may already be met. In May 2026, MIT Technology Review reported that over two dozen states were considering similar laws.^[source] Whether prices follow is not yet known.

What this means if you're buying now

Prices for certified kits in California are still settling. Our kit tracker shows each kit's price with the date we checked it, and the calculator shows the payback at today's price. See how today's prices compare with rooftop solar in plug-in vs rooftop solar.