Does balcony solar pay?
A plug-in system costs around $1,400 before you have produced a single kilowatt-hour. The honest answer on when, or whether, that comes back is a range, not a number, and the range depends more on how you use the power than on how much sun hits the panel.
The CESA numbers
CESA's "Plug-In Solar" guide (Bentham Paulos, June 2026) runs the arithmetic on an 800 W system at $1.75/W, roughly $1,400 installed, across two capacity factors and two values for the power it produces.
| Capacity factor | Output | Value of a kWh | Simple payback |
|---|---|---|---|
| 15% | 1,051 kWh/yr | $0.30/kWh | 4.4 years |
| 10% | 700 kWh/yr | $0.15/kWh | 13.3 years |
Source:CESA, "Plug-In Solar," June 2026, Table 1. Bright Saver's independent estimate for the same category of system is two to seven years. Both assume every kilowatt-hour produced is actually used, which is the part that depends on you, not the panel.
What moves the number
Sun, tilt, and your rate each shift the payback, but self-consumption decides more than all three combined. An 800 W system can outproduce a small apartment's own draw at midday: against a typical base load of 200 to 400 W from a refrigerator, lights, and standby devices (the figure from ourload-shifting post), the surplus above that line goes nowhere, because no US law lets you sell it back (see below). A system that mostly makes power the home is already drawing pays back on CESA's low end; one whose midday peak overshoots an empty apartment's base load pays back on the high end, or not at all, regardless of how sunny the balcony is.
Why no US law pays for exports
Every one of the ten state laws in force as of October 2026 either places the device outside net metering or stays silent on export compensation. Utah, Maine, and Virginia each say so in the statute's own words: the device is "not eligible for net metering." California goes further and exempts the device from interconnection entirely, which rules out the metering relationship net metering depends on. None of the ten pays for a kilowatt-hour sent back to the grid. See the fullstate-by-state table for every provision.
A worked example per rate type
The same system earns a different return depending on what it is offsetting. Each example below links the rate guide the figures come from; run your own household's numbers in the calculator link under each one.
Fixed time-of-use: PG&E EV2-A
EV2-A prices off-peak power (midnight to 3 p.m.) around 23¢/kWh and peak power (4 to 9 p.m.) around 54¢/kWh, per ourPG&E rate guide. A panel that produces through the afternoon offsets some off-peak hours outright and, on a longer summer day, reaches into the shoulder before the evening peak begins. The spread is the opportunity: the same kilowatt-hour is worth more than double depending only on when it lands.
See this system on EV2-A →Hourly pricing: ComEd
ComEd's Hourly Pricing program has no fixed peak window; every hour is priced by the wholesale market, plus roughly 8¢/kWh delivery. On June 29, 2026 that meant about 2¢/kWh overnight and over 60¢/kWh between 7 and 8 p.m., a 30× swing in one day, as recorded in ourComEd Hourly Pricing guide. A plug-in system cannot shift when it produces, but it still earns its best return on the rare expensive afternoon hour it happens to cover, and loses nothing on the cheap ones it would have offset anyway.
See this system on ComEd Hourly Pricing →Flat rate
A household on a flat rate, 15¢/kWh for this example, has no time-of-use spread to capture at all. Every kilowatt-hour the panel offsets is worth exactly 15¢ no matter the hour, which lands this case at CESA's slower end: the same system that pays back in 4.4 years against a 30¢ value takes longer against 15¢. A flat-rate household's return rests entirely on self-consumption, with no time-of-day advantage to help it along.
See this system on a flat rate →Run your own numbers
These examples use published rate figures, not your bill. The calculator takes your state, your system size, and your own rate, and gives you a payback range built on your household instead of someone else's.
Try the calculator →Frequently asked questions
What is the real payback range for a plug-in solar system?
CESA's June 2026 guide puts it at four to thirteen years, depending almost entirely on what a kilowatt-hour is worth to you. At a 15% capacity factor (1,051 kWh/yr) and 30 cents/kWh, a $1,400 system pays back in 4.4 years; at a 10% capacity factor (700 kWh/yr) and 15 cents/kWh, the same system takes 13.3 years. Bright Saver's independent estimate is two to seven years. Neither number assumes you sell any power back to the grid, because in the US today you cannot.
Why does self-consumption matter more than sunlight?
Because an 800 W panel can produce more than a small apartment uses at that exact moment, and the surplus is wasted unless something is running to absorb it. Against a typical 200 to 400 W base load of a refrigerator, lights, and standby draw, midday output above that line does nothing for your bill. The fix is the same one behind every optimizer schedule: run a flexible load, like a water heater or an EV charger, during the hours the panel is producing, so the kilowatt-hour gets used instead of discarded.
Can I sell surplus power back to the grid?
No, not under any of the ten state laws in force as of October 2026. Utah, Maine, and Virginia each say so directly: the device is not eligible for net metering. The rest either stay silent on export compensation or, in California's case, exempt the device from interconnection entirely, which forecloses the metering relationship net metering runs through. A plug-in system earns its return only by covering load you would otherwise have bought from the grid, never by selling anything back.
Which rate plan makes a plug-in system pay back fastest?
Whichever one prices your most expensive hours highest and puts them in the window your panel is already producing. A PG&E EV2-A household offsetting midday-to-afternoon load against a 54-cent peak gets more value per kilowatt-hour than a flat-rate household at 15 cents, even from the identical system. An hourly plan like ComEd's splits the difference: most hours are cheap, but the system still earns its best return on the rare expensive afternoon. Run your own numbers in the calculator below rather than assuming your plan behaves like someone else's.
About Hungry Machines
Outsmart your electric bill - Hungry Machines Energy provides an energy management system that shifts HVAC, EV charging, home batteries, and other electric loads to cheaper hours for homes and buildings with solar power or variable electricity rates.