What Is Plug-In Solar? Balcony Solar Explained (Complete Guide)

Short answer: plug-in solar, often called balcony solar, is a small solar system (usually one to four panels and a microinverter, up to 1,200 W in most US states) that you connect to your home through a standard wall outlet. Its power is used first by whatever is running in your home, so you buy less from the grid. No roof, no electrician and, where a state law allows it, no utility approval.

How plug-in solar works

1. Panels on a balcony railing, wall, patio or yard turn sunlight into direct current (DC).
2. A microinverter converts the DC into alternating current (AC) matched to your grid's voltage and frequency. It's the brain of the system, and it shuts off within a fraction of a second if the grid goes down or you pull the plug.
3. The inverter's cable plugs into an ordinary outlet. From there, solar power flows into your home's wiring.
4. Your appliances use the solar power first, because it's the nearest source. If the panels produce 500 W and your home is using 300 W, the meter sees only 200 W going out to the grid. If you're using 800 W, you buy just 300 W from the utility.

Nothing needs rewiring. That's the whole idea: solar that anyone can set up in an afternoon.

What's in a kit

• Solar panels: usually 1 to 4 modules of 200 to 450 W each. Rigid glass panels last longest; flexible panels are lighter but degrade faster.
• Microinverter: the part that must be certified (UL 1741, or the newer UL 3700 for plug-in use).
• AC cable with plug: a standard 120-volt US plug.
• Mounts: railing hooks, wall brackets or a ground stand.
• Optional: a monitoring app or smart plug, and in some kits a battery.

Where it came from

Plug-in solar took off in Germany, where it's called a Balkonkraftwerk ("balcony power plant"). Germany simplified the rules in 2024, and by September 2026 about 1.53 million systems were registered with the federal network agency. Several European countries followed. In the US, Utah passed the first law in 2025, and in 2026 a wave of states joined. Great Britain legalized plug-in solar on 27 August 2026 with an 800 W limit (see plug-in solar in the UK).

Is it legal where I live?

In the US, it depends on the state. Six states had plug-in solar laws in force in October 2026 and four more had signed laws starting in 2027. Most allow up to 1,200 W without utility approval, as long as the equipment is certified. Elsewhere, your utility's interconnection rules apply. See the 50-state map and how the laws work.

What it costs and what it saves

• Cost: roughly $600 to $2,000 for a grid-tied kit in 2026, more with a battery.
• Production: an 800 W kit makes about 600 to 1,400 kWh a year, depending on sun and mounting.
• Savings: typically $80 to $350 a year, most in high-price states like California.
• Payback: about 3 to 13 years. Panels last 25 years or more.

Full numbers by state: how much balcony solar saves. Or try the calculator.

Who plug-in solar is for

• Renters and apartment dwellers who can't install rooftop solar (with the landlord's permission: see solar for renters).
• Condo owners with a sunny balcony.
• Homeowners who want to try solar cheaply, or add a little capacity in a yard or on a shed wall.

It's less useful if your only space faces north, is heavily shaded, or your electricity is very cheap. Read Is balcony solar worth it? for the honest pros and cons.

Is it safe?

Certified kits are designed to be safe: the plug goes dead when you pull it out, and the inverter stops during outages. The real risks are uncertified equipment, extension cords and overloading an already busy circuit. Our safety guide covers what to avoid, and how to install balcony solar walks you through setup.

Plug-in solar vs other options

Ready to pick one? Start with which size you need, then the kit buying guide.

Frequently asked questions