Sizing a solar system isn't guesswork or a sales pitch — it's arithmetic. Here's how to turn the appliances you actually run into the right inverter, battery and panel array.
Start with your load, not a package
The right system starts from what you run and for how long — not from a fixed 'home package'. List your appliances, their wattage, and the hours you use each per day.
Multiply watts by hours to get watt-hours, and add them up. That daily figure in kilowatt-hours (kWh) is the foundation of every other decision.
Three numbers that matter
- Inverter size (kVA) — must handle everything that could run at once, plus headroom for surge.
- Battery capacity (kWh) — enough usable energy for the hours of backup you want.
- Panel array (kW) — enough daily generation to recharge the battery and run daytime loads.
Let the audit do the maths
Our free audit does all of this in your browser: add appliances, set your state and backup target, and it sizes the exact inverter, battery and panels — with a cost and savings estimate.
A site survey then confirms everything before installation, so you never over- or under-buy.
Reading is a good start.
Turn it into a system sized for you — run a free audit and see the numbers for your own home or business.