What Is Plug-In Solar? How Balcony Solar Works and Where It Is Legal

Short answer: plug-in solar (also called balcony solar) is a small solar system, usually one to a few panels and a microinverter, that you connect to your home through a plug instead of having it wired in by an installer. The power it makes goes into your home’s circuit and is used by whatever is running at the time, so you buy less from your utility. US state laws cap it at around 1,200 watts, a fraction of a typical rooftop system. It’s legal without utility approval only in states that have passed a plug-in solar law (ten had signed one as of our last check), and those laws increasingly require a certified system. In our math, an 800 W kit facing south saves roughly $70 to $490 a year, depending on your state and how you mount it.

How plug-in solar works

A kit has three main parts, as the California Assembly’s analysis of SB 868 describes them:

• One or more solar panels on a stand or a mount, for a balcony railing, a wall, a patio or a yard.
• A microinverter, which turns the panels’ direct current (DC) into the alternating current (AC) your home uses.
• A cord that connects to a 120 V receptacle. Some systems add a battery.

Once it’s connected, the inverter feeds AC power into that branch circuit. Your fridge, router or TV use it first, anywhere in the home, and you draw that much less from the grid. Nothing is stored unless the kit has a battery, and the system only produces while the sun is on the panels.

What can it power?

Less than people hope, more than nothing. The committee analysis notes that one panel at peak output can run a standard refrigerator, a computer or some lights. A full 1,200 W system is about what a window air conditioner draws, KQED points out. But that’s in full sun. Over a day, output rises and falls with the sun, and a shaded or north-facing spot produces much less.

It won’t cover a whole home, and it isn’t backup power. California’s law, for example, requires a certified feature that isolates the system from your home’s wiring during a power outage. If you want power during outages, you need a battery or a portable power station that’s designed for it; our power station sizer shows what size.

Plug-in solar vs. rooftop solar

	Plug-in solar	Rooftop solar
Size	Up to about 1,200 W where a state law sets a cap	Usually several kilowatts
Installation	You set it up and plug it in	Hard-wired by a licensed installer, inspected
Utility	No approval or fee in states with a plug-in law	Interconnection agreement and approval
Moves with you	Yes	No
Who it suits	Renters, condos, small spaces, smaller budgets	Owners with a good roof who plan to stay

Existing plug-in models range from about $300 to $2,200 depending on size, according to KQED. Advocates say a system can meet up to 20% of a home’s electricity needs and save as much as $500 a year in a small apartment. That’s their estimate, not ours; our own math for an 800 W kit in every state is in how much plug-in solar really saves. It depends heavily on your electricity rate (see the average electric bill and price in your state) and your sun. Run your own numbers in our plug-in solar calculator, with real rates and every assumption shown.

Balcony or backyard: it works for houses too

The name comes from Europe, especially Germany, where apartment dwellers hang panels over their balcony railings. In the US, plug-in solar fits houses as well: panels can hang from a balcony, out a window, or be set up in the backyard (KQED). Houses usually have more space and more sun; apartments usually have a landlord to ask first. Our guides cover both: plug-in solar for renters, with what each state law lets a landlord say, and plug-in solar for houses, with stands, shed roofs and HOAs.

Is plug-in solar legal where I live?

It depends on your state. Without a plug-in solar law, your utility’s interconnection rules for rooftop solar apply, which usually means an application, approval and sometimes a fee before you plug anything in.

• Ten states had signed a plug-in solar law as of October 18, 2026, when we last read them all on the legislatures’ own sites. Six were in force (Utah, Maryland, Vermont, Maine, Colorado and Connecticut), and Virginia, New Hampshire, California and New Jersey start in early 2027.
• Utah passed the first US law in 2025.
• California signed SB 868 on September 30, 2026. From January 1, 2027, Californians can plug in up to 1,200 W AC per home without utility approval or fees, if the system is certified. Read our full guide to the California plug-in solar law.
• Connecticut’s rules took effect on October 1, 2026: one device of up to 1,200 W per meter, with no utility approval or fee if it meets the codes and is certified. See what Connecticut’s plug-in solar law allows.
• New York’s bill passed both houses on May 28, 2026, but as of November 3 the Assembly’s site doesn’t show it delivered to the governor, so it isn’t law yet.
• pv magazine reports that 35 states considered a plug-in solar bill in 2026.

Our guide to plug-in solar laws by state covers each law we’ve read on the legislature’s own site, with its cap, its rules and the date we checked it.

Is plug-in solar safe?

That’s the open question, and it’s why the newer laws ask for certification. Household circuits were designed for power flowing one way, from the panel to your appliances. UL Solutions’ white paper on plug-in PV describes three main risks:

• Hidden overloads: solar feeding into a circuit can let your appliances draw more current than the wiring is rated for without tripping the breaker.
• Touch safety: the plug’s blades can be live when the panels are in the sun.
• GFCI protection: the ground-fault protection used outdoors and in wet areas assumes power flows one way.

UL’s answer is UL 3700, a certification program for plug-in systems it opened in January 2026, which covers accidental contact, overloads and power flowing the wrong way (UL Solutions). The first microinverter claiming UL 3700 compliance was announced in July 2026 (Electrek), but a certified part doesn’t make a certified kit. Here’s how to check whether a kit is really UL 3700 certified; as of October 12, 2026, we hadn’t found a complete kit reported as certified. The electrical code itself has no definition of plug-in solar yet, though six proposed amendments would add one.

Until certified kits reach stores, follow your utility’s current rules, use the maker’s instructions, and call a licensed electrician for anything beyond plugging in.

Who it’s for, and who should wait

A good fit if you rent or can’t put solar on your roof, have a spot that gets several hours of direct sun, pay a high electricity rate and use power during the day.

Wait if your state has no plug-in law yet (or, in California, until certified kits are on sale), if your only spot is shaded most of the day, or if your lease or HOA forbids it. And if your goal is backup power during outages, plug-in solar on its own won’t do it.

Bottom line

Plug-in solar is small, portable and cheap compared with rooftop solar, and it’s arriving in the US fast, led by Utah and California. Check three things before you buy: your state’s law, whether the kit is certified as a whole system, and what it will realistically save at your rate. The Start here guide walks you through them in order.