Features
How Solar Setup Calculator works
A guided three-question flow turns your appliances and your region into a sized panel, battery, and inverter system — with a cost and payback estimate at the end.
How the calculator works
The first time you open the app you answer three questions: Where you are, what Power you need, and how much Backup you want. From there the maths is a simple chain, in plain English:
- Your appliances give a daily kWh demand (watts × hours per day × days per week).
- Your region gives the peak sun-hours available there.
- Demand divided by sun-hours gives the panel wattage you need.
- Your chosen days of autonomy size the battery capacity.
- Your largest simultaneous load sizes the inverter.
No formulas to fill in and no spreadsheets — you adjust the inputs, the app keeps the chain in sync, and you can change any value later from the review screen.
Where: the region picker
You choose your location from a manual region picker. The app does not use GPS, does not request location permission, and does not track where you are. The region you pick maps to a built-in table of peak sun-hours.
If you want sharper numbers for your exact site, the optional NASA POWER refresh makes a single network call with just a latitude and longitude. No account, no email, and no device identifier is sent — and you can skip it entirely and stay fully offline.
Power: the appliances list
You build a list of the things you'll run — a fridge, lights, a laptop, a water pump — and for each one you set its wattage, how many hours a day it runs, and how many days a week. The app multiplies that out into a daily and weekly kWh figure.
It ships with a starter catalogue of common appliances so you're not staring at a blank screen, but every value is editable. Change a wattage, add your own device, or delete anything that doesn't apply.
Backup: days of autonomy
"Days of autonomy" is how long your battery bank should keep the system running with no meaningful sun — a stretch of heavily overcast days. More autonomy means a bigger, more expensive battery bank.
The default is 0 days, because most setups size the battery for a normal day–night cycle and don't need a multi-day cushion. If your site is consistently cloudy, or losing power is not an option, dial it up and watch the battery size and cost respond.
The results screen
Once the three questions are answered the app produces a sized system:
- Panel watts and count — total array size and how many panels at your chosen wattage.
- Battery capacity in kWh for your days of autonomy.
- Inverter sizing in VA for your peak simultaneous load.
- Daily energy demand — the kWh your appliances draw.
- System cost estimate in your chosen currency.
- Payback period versus your entered grid kWh price.
Every input remains editable from the review screen, so you can try a bigger battery or a different panel wattage and see the cost and payback move immediately.
Pro features
The app is free to use. A one-time $6.99 lifetime in-app purchase unlocks Pro — no subscription, no recurring charge.
PDF export
Export any setup as a clean one-page PDF you can hand to an installer, attach to a quote request, or print for your project binder. It captures the full sized system, your appliance list, and the cost and payback summary.
Side-by-side comparison
Put two saved setups next to each other and see exactly how a change — more panels, a bigger battery, a different region — moves the cost and the payback period. It turns "what if" into a decision you can see.