Plug-in solar is a small solar system, usually 180 to 1,200 W of panels wired to a microinverter, that plugs into a standard 120 V wall outlet. The inverter turns the panels' DC into house power synced to the grid; your appliances draw from it first and from the utility second. A typical 800 W kit makes 900 to 1,300 kWh a year on a tilted mount, offsets 10 to 25% of an apartment's use, and is explicitly legal without utility approval in 6 states as of October 17, 2026, with 5 more taking effect in 2027.
Key facts
Kits sold in the US cost about $285 to $1,600 (October 2026), or $1.15 to $2.50 per watt; there is no federal tax credit for 2026 purchases.
Legal without utility approval in Colorado, Connecticut, Maine, Maryland, Utah, Vermont today; California, New Hampshire, New Jersey, New York, Virginia follow in 2027.
Most laws cap systems at 1,200 W AC per dwelling (Colorado: 1,920 W) and require certification by UL or an equivalent lab.
A microinverter certified to UL 1741 shuts off within milliseconds in a blackout; the new UL 3700 standard (December 2025) adds protection for your wiring and plug.
Germany has more than a million balcony systems under an 800 W rule; the US is roughly where Germany was in 2022.
How does a plug-in solar kit work?
The kit feeds the circuit it is plugged into. Power flows to whatever is running; anything left over goes out through the meter.
Three parts do the work. The panels are ordinary solar modules, one to four of them. The microinverter converts their DC output to 120 V AC that is synchronized to the grid's 60 Hz; it is the part that must be certified, because it decides what happens in a blackout (it must shut off) and how much current it will push into your wiring. The plug is a normal grounded plug on a short cord. Nothing is hard-wired, which is why renters can own one and why it leaves with you when you move.
When the sun is up, the inverter pushes power into the circuit it is plugged into. Your home's loads draw from the nearest source first, so a 300 W fridge-plus-router baseline comes from the panels instead of the grid. If the kit is making more than the home is using, the surplus runs backward through your meter to the grid. In most states that surplus is not paid for, so sizing the kit to your daytime baseline, not to the biggest kit you can buy, is what makes the economics work.
What is in a kit?
Panels: 180 to 450 W each, rigid glass for ground or rail mounts, flexible or lightweight for railings (Bright Saver's are about 11 lb).
Microinverter: 180 to 1,200 W AC output; one or two MPPT inputs; UL 1741 listing at minimum (APsystems EZ1-LV, Hoymiles HiFlow Pro, EcoFlow STREAM are the common US units).
Cable and plug: 15 ft or so of outdoor-rated cord ending in a NEMA 5-15 plug. UL 3700 units may use a dedicated receptacle instead.
Mount: railing hooks, a tilt stand, or ground frame. Sometimes sold separately.
Optional battery: 1 to 3 kWh with its own outlets (EcoFlow STREAM Ultra, Craftstrom's 3 kWh kit). Adds evening use and outage power; adds $500 to $1,300.
Optional meter or app: without one you cannot see what it makes. A $20 plug-in meter is enough.
How much power does it actually make?
Rated watts are the panel's output under lab conditions. Real output over a year depends on where you are, how the panels face, and how they are tilted:
800 W kit
Tilted, facing south
Tilted, east or west
Vertical on a railing, south
Phoenix / Denver (sunny)
~1,300–1,400 kWh/yr
~1,100–1,200
~900–1,000
Texas / Southeast
~1,150–1,250
~1,000
~800–900
Northeast / Midwest
~1,000–1,100
~850–950
~700–800
Approximate figures from PVWatts-style state yields with a 14% system-loss factor; vertical mounting modeled at about 30% below ideal tilt. Boston University's April 2026 study found vertical balcony mounts yield "substantially less" than tilted ones.
One real-world data point: an APsystems customer with a 395 W panel saw it peak at 354 W (90% of rating) and average about 2 kWh a day. That is the right mental model: a kit delivers 85 to 90% of its sticker on a clear noon, and the yearly total is what matters. Use the calculator for your state and mount.
Is it safe to plug solar into an outlet?
With a certified kit, used as directed, yes. The engineering concern is specific: a plug-in inverter adds current to a circuit downstream of the breaker, so the breaker cannot protect that wire from the combined load; GFCIs can be confused by reverse flow; and an inverter never tested for user contact can leave plug blades live in the sun. UL 3700, published in December 2025, requires protection against all three. The practical rules are simple: under about 400 W on a shared circuit, a dedicated 20 A circuit above that, never an extension cord. Full explanation on Is plug-in solar safe? and UL 3700 explained.
Is plug-in solar legal in the US?
State by state. 6 states have laws in force that exempt certified kits under a wattage cap from utility interconnection and permits; 5 more have signed or passed laws for 2027; 24 others saw bills in 2026; and 16 have no bill. Where there is no law, plugging a grid-tied kit into an outlet falls under your utility's interconnection agreement, which usually requires an application, and the 2026 National Electrical Code does not recognize plug-in PV at all.
Savings = kilowatt-hours you use from the kit × your electricity rate. At the July 2026 US average of 18.3¢/kWh, an 800 W kit that delivers 1,000 usable kWh saves about $180 a year; at California's 33.6¢ it is roughly $330, at Utah's 13.1¢ about $130. Against a $700 to $1,000 kit that is a 3 to 8 year payback, and under 2 years in the highest-rate states. Two things move the number most: tilting the panels instead of hanging them flat (+30 to 40%), and using the power as it is made, since exports are unpaid in most states. Details on the cost and payback page.
Plug-in vs balcony vs portable vs rooftop
Plug-in (balcony) kit
Portable panel + power station
Rooftop solar
Connects to house wiring
Yes, via an outlet
No
Yes, hard-wired by an installer
Size
180–1,200 W (1,920 W in CO)
100–400 W
5–10 kW
Cost
$285–1,600
$400–2,000
$20,000–40,000 before incentives
Yearly savings
$100–400
Small (devices only)
$1,500–6,000
Permits / utility
None in enacted states; interconnection elsewhere
None
Permit + interconnection always
Renters
Yes
Yes
No
Works in a blackout
Only with a battery model
Yes
Only with a battery
Moves with you
Yes
Yes
No
Who should buy one (and who shouldn't)
Good fit: renters and condo owners with a south-, east- or west-facing balcony, patio or yard; homes with daytime loads (someone home, home office, fridge and freezer); anyone in an enacted state paying 15¢/kWh or more; people who want solar without a $25,000 commitment or a roof.
Poor fit: a shaded or north-facing spot; electricity under about 12¢/kWh; homes that are empty all day with no battery; anyone in a no-law state whose utility requires full interconnection for any grid-tied device; anyone expecting backup power from a kit without a battery.
Yes. "Balcony solar" (Balkonkraftwerk) is the European name, where more than a million German homes use 800 W kits on 230 V grids. US laws and retailers say "plug-in solar" or "portable solar generation devices." Same idea, different voltage and certification.
How much electricity does a plug-in kit make?
Roughly 1.1 to 1.6 kWh per year for each watt of panel on a tilted south-facing mount, so an 800 W kit makes about 900 to 1,300 kWh a year in most of the US. Hang the same panels flat on a balcony railing and expect 30 to 40% less. One retired solar professional's 395 W APsystems panel peaked at 354 W and averaged about 2 kWh a day.
Does it lower my bill even without net metering?
Yes, as long as you use the power as it is made. Your appliances draw from the panels first and the grid second, so every kilowatt-hour you consume from the kit is one you do not buy. Most state plug-in laws exclude net metering, so exported surplus is unpaid, which is why kits are sized to a home's daytime baseline.
Does plug-in solar work during a blackout?
No. Grid-tie microinverters must shut off when the grid goes down (anti-islanding, UL 1741) so they cannot energize a line a crew is repairing. Kits with a battery and their own outlets can power devices in an outage.
Why do most state laws cap it at 1,200 W?
Because the solar current enters your circuit downstream of the breaker. At 1,200 W on 120 V that is about 10 A; on a 20 A circuit the combined current stays within the wire rating. Germany's 800 W rule on 230 V circuits is the same arithmetic. Colorado allows 1,920 W but requires an electrician and a dedicated circuit above about 391 W.
Do I need an electrician or a permit?
In states with a plug-in law, a certified kit under the cap generally needs neither, with exceptions: Maine requires an electrician above 420 W, Colorado above about 391 W. In states without a law, your utility's interconnection process applies and may require both. A dedicated 20 A circuit is good practice anywhere above about 400 W.
Is it worth it in 2026?
At $1.15 to $2.50 per watt with no federal credit, payback runs 3 to 8 years in most states and under 2 years at California or Hawaii rates, on hardware that lasts 20+ years. It is worth it if you have a sunny south-, east- or west-facing spot, daytime loads, and a state that allows it. It is not worth it on a shaded north balcony or if your rate is under about 12 cents.
What should I buy?
A kit whose inverter is at least UL 1741 listed, ideally UL 3700 certified, that fits under your state's cap. See the kit comparison for dated prices and certification status; in October 2026 the US market is Bright Saver, Craftstrom, and kits built on APsystems or Hoymiles microinverters, with the European brands expected after California's law starts in January 2027.