sunsolarcalculator.com

Balcony solar: is a plug-in kit worth it?

A plug-in balcony system has a lot going for it, but it is a very different set of considerations, and the investment opportunity is smaller. Play around with this, but if you’re in California, I built a calculator specific to you: www.plugincalifornia.net.

What’s in a plug-in kit

Parts of a plug-in solar kit Panels, a microinverter, and a cord with anti-backfeed protection make up the kit, certified together. It plugs into a wall outlet and powers your home; a bar in the house shows how much power the home is using, and when that is more than the panels make, the rest comes in from the grid. On some kits a usage reader near the meter tells the inverter to hold back. Then the meter and the grid. The kitcertified together as one system DC→AC Panelsmake DC power Microinverterconverts to AChouse voltage Anti-backfeedcuts off in anoutage Wall outlet Your home usage reader (some kits):tells the inverter to hold back kWh Metercounts less Grid

The kit

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Starts as the Mango Power S 1200 W kit: four 300 W panels, each with its own 280 VA inverter, listed at $2,698 in October 2026. Change anything to match yours.

Your usage

Best: your own meter data

A Green Button file from your utility shows your home’s real use, hour by hour. It gives the most accurate result. It’s read in your browser and never sent anywhere. How to get it.

Or estimate it
From a year of bills, or your utility account.
Each choice runs five real homes that use power that way, hour by hour.
What your home draws with everything off: fridge, router, chargers. It decides how much of a kit’s midday output you can use. Leave it blank to use what homes like yours draw.

Your rate

Some cities and states tax electricity. Solar avoids the tax on every kWh it replaces. Check your bill.
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Where it stands

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Will it fit?

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Pick the closest match. Older panels are listed because a lot of balcony kits are built from secondhand ones. Picking a size sets watts each to its typical rating; change that if your panel’s label says otherwise.
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What this does and doesn't do

Power sent out earns nothing, unless you already have solar. Most places give plug-in kits no export credit of their own, so what the home doesn’t use as it’s made goes out unpaid, and the share you use matters more than the nameplate. If the home already has panels on net metering or net billing, the kit’s power goes out through the same meter and is credited the same way, on the plan you pick.

Legality isn’t modelled, anywhere. Rules for plug-in solar are changing fast and differ by state and utility. This calculator doesn’t tell you what’s permitted where you live. Ask your utility before you buy.

It works hour by hour. Five real homes that use power the way you picked (or your own meter data), on real days of your area’s weather, against what the panels make in each hour. Production comes from NLR’s PVWatts v8 at six tilts from 20° to upright and eight facings, with each month held to 896 measured runs. Upright matters more than latitude suggests: a vertical south panel makes 0.52 of a 20° roof in Miami and 0.72 in Boston, and it makes most of that in winter.

Shade is counted in hours, not mapped. The hours you give are taken as the panel’s best ones in each month. Outside them it still sees open sky, worth about a quarter of direct sun. A railing that gets only early-morning sun will do worse than this says.

Rates you can check. The prices that fill in for your area, and the published plans you can pick, each show their source and date. Where I can’t find a figure I can check, or it’s over a year old, the page says so. Your bill beats all of them: type in your own.

Not modelled: a real shade study, wind loading, how you fasten it, whether your circuit can take it, battery storage, or any tax credit. Enter a price you'd actually pay.

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