Will your balcony pay for plug-in solar?
Lay your iPhone on the railing. Sunperch measures where the panel would face, how it tilts and what shades it, then estimates what it will make, checks your state's rules and drafts the notice for your landlord.
Coming to the App Store in late October 2026. Android version planned for this winter.
Drag across the sky to turn your balcony.
This preview uses your state's average sunshine and an open sky. The app measures your actual railing with your phone's sensors and scans the trees and buildings around it. Open the full estimator
9 states have passed plug-in solar laws. No two have the same rules.
Power limits, certification, utility notice and renter protections all vary. Some laws are already in effect, others start in the coming months. We track all 50 states and DC and update the data every week.
A ZIP-code calculator can't see your balcony.
Online calculators assume a tilted, south-facing roof. A balcony panel hangs on a railing, faces wherever your building faces and sits in the shadow of whatever is next door. Here is the same 800 W kit in Virginia:
- On a south-facing roof, tilted 37° What most online calculators assume1,090 kWh/yr
- On a south-facing balcony railing Hanging vertically690 kWh/yr
- On a west-facing railing Afternoon sun only554 kWh/yr
- On an east-facing railing Morning sun only612 kWh/yr
- On a north-facing railing Mostly diffuse light252 kWh/yr
Hanging the panel vertically costs about 37% compared with the roof, and direction matters even more. And that's before shade from trees and neighboring buildings, which only an on-site scan can measure. Estimates from the Sunperch model with NASA POWER sunshine data for central Virginia.
About a minute on the railing. Everything you need before you buy.
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Pick your state Free
Power limit, certification, utility notice and renter rules, with the date the law takes effect and links to the bill.
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Lay your phone where the panel will go Free
Sunperch reads direction and tilt in seconds. If a metal railing confuses the compass, point the camera at the sun once to correct it.
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Scan the shade Pro
Sweep the camera from east to west along the skyline. Trees, buildings and the balcony above go into the estimate.
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See output and payback Free rangePro detail
Yearly kWh as a range for free. Month-by-month output, bill savings at your state's electricity price and years to pay back with Pro.
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Check your kit against the rules Free summaryPro detail
Enter the inverter's output and certification. Each rule reads "looks like it meets this", "may not meet this" or "confirm with the relevant party", with a next step.
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Send the report and notice Pro
A PDF with your measurements, shade chart and estimate, plus a draft notice for your landlord or association that you check and edit.
Renting? Tell your landlord the right way.
In Virginia and New Jersey a landlord can't simply ban a balcony panel, but you must give written notice first: 7 days ahead in Virginia, 14 in New Jersey, with proof the device meets the law and where it will go.
Sunperch fills a notice from your measurement: the device, its output, its certification, the planned spot and the law it refers to. You confirm each item the law asks for, edit any line, and send it as a PDF.
The draft lists facts and quotes the law's name and link. It never argues your case or promises an outcome, and every page says it is not a substitute for an attorney.
November 2, 2026
To: Landlord
Re: Notice of plug-in solar device at [your address]
I am writing to tell you that I plan to place a plug-in solar device at the address above. The details are:
- Device: [model]
- AC output power: 800 W
- Certification: [certification]
- Planned location: balcony railing
- Measured orientation: facing south-west (214°), tilt 90°
- Earliest placement date: November 9, 2026 (7 days after this notice)
Reference: Virginia plug-in solar law (HB 395 / SB 250).
Effective date listed: 2027-01-01.
Sincerely,
[name]
Draft generated by software, not written by a lawyer, and not a substitute for an attorney. Template checked against regulation data dated September 30, 2026.
Free to check. $4.99 once for the full picture.
No subscription, no account, no ads. Pay once, keep it, and share it with your family.
| Feature | Free$0 | Pro$4.99 once |
|---|---|---|
| State rules for all 50 states and DC | ● | ● |
| Direction and tilt reading with sun calibration | ● | ● |
| Yearly output range | ● | ● |
| Rules check summary for your kit | ● | ● |
| Shade scan of trees and buildings | – | ● |
| Month-by-month output, savings and payback | – | ● |
| The reasoning behind each rule, with source links | – | ● |
| PDF report and notice letter for your landlord or HOA | – | ● |
| Save and compare every spot on your balcony | – | ● |
One-time in-app purchase. Family Sharing supported. Restore it any time on a new phone.
Your balcony stays on your phone.
- No account. There's nothing to sign up for.
- Nothing uploaded. Location, camera and measurements are processed on the device.
- One public download. The app checks for new law data at most once a week. It's this file.
Questions
What is plug-in (balcony) solar?
A small solar kit, usually one to four panels with a micro-inverter, that plugs into a regular outlet. It feeds power into your home's circuits so you buy less from the utility. Most U.S. laws cap these kits at 1,200 W of output.
Is it legal where I live?
As of September 30, 2026, 9 states have passed plug-in solar laws, and many more have bills in progress. Our state-by-state tracker lists the power limit, certification, utility notice and renter rules for each one, with links to the bill text.
Can my landlord say no?
It depends on the state. Virginia and New Jersey, for example, limit a landlord's ability to ban these devices but require you to give written notice first (7 and 14 days). Other states say nothing about renters. Sunperch shows what your state's law says and drafts the notice; it does not decide whether your situation is covered.
How accurate is the estimate?
The model was checked against NREL's PVWatts at 10 U.S. cities and three orientations: on average within 6%, at worst 13%. Results are shown as a range. Your biggest sources of error are usually direction and shade, which is exactly what the app measures on site.
My railing is metal. Will the compass work?
Metal railings can throw off a phone's compass. Sunperch detects the interference and asks you to point the camera at the sun once to correct the heading. On a cloudy day you can enter the direction by hand.
What languages is the app in?
English, with a Simplified Chinese option in Settings. The PDF report and the notice letter are always in English.
Is there an Android version?
Android version planned for this winter. Leave your email below and we'll write once when it's available.
Is this legal advice?
No. Sunperch gives estimates, references and suggestions. It is not legal or electrical advice and does not replace an attorney. Always check the bill text, your utility and your landlord or association.
Get one email when it matters.
The day the app launches, or the day your state passes a plug-in solar law. Nothing else.