What is balcony solar?

How it works

• Panels, usually one to four, hang on a balcony railing, sit on a stand, or mount on a wall or patio.
• A microinverter turns the panels' direct current into the alternating current your home uses.
• A plug connects it to an outlet. Whatever your home is using at that moment uses the solar power first.
• A shut-off feature stops the system from sending power out during a blackout, protecting utility line workers. Every U.S. state law we track requires one.

Some systems add a battery so that daytime solar can be used in the evening. Those cost more; see the kit tracker.

Is it legal in the U.S.?

In 10 states, yes, under a specific plug-in solar law: California, Colorado, Connecticut, Maine, Maryland, New Hampshire, New Jersey, Utah, Vermont and Virginia. Most cap the size at 1,200 watts; Colorado allows 1,920. Some laws are not in force yet. Elsewhere, connecting solar to your home generally goes through your utility's interconnection process. See the full state tracker.

How much can it produce and save?

It depends on where you live, which way the panels face, how they are mounted, and above all how much power your home uses while the sun is up. As one example from our calculator, an 800 W system hanging vertically on a south-facing railing in California produces roughly 880 kWh a year before shade (PVGIS data, 14% losses). At California's average residential rate (about 33 cents per kWh, EIA) that would be worth about $290 a year, but only if your home used every bit of it the moment it was made. In practice part of it flows out to the grid, and no state law we track pays for that.

Run your own numbers. The calculator shows every assumption.

What to check before buying

1. Your state's rules: size cap, utility notice, required certification. Some states, like California, require the whole system to be certified as plug-in solar.
2. Certification: a maker saying "UL 3700 compliant" is not the same as a listing in a certifier's directory. What UL 3700 is.
3. Output, not panel watts: the inverter's AC output is what counts toward state caps.
4. Your lease or HOA: only some states protect renters and HOA members. Renters and HOAs.
5. No federal tax credit: the 30% residential clean energy credit does not apply to costs after Dec. 31, 2025. ✓Verified Source: IRS Form 5695 instructions

Safety

Use only equipment certified for plug-in use, follow the maker's instructions, plug into an outlet in good condition, and never use adapters or modify certified equipment. If your state requires an electrician for larger systems (Maine does above 420 W), use one.