System Size Calculator
Estimate array size from monthly bill or annual electricity use.
TheSolarCost calculator suite
Make the solar quote make sense.
Start with a system-size or cost estimate, then pressure-test storage, roof fit and payback with country-aware inputs.
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8launch-country models
Noemail gate or quote form
Livein-browser calculations
Choose your next calculation
Each tool answers one decision clearly, without mixing solar-only, battery and finance assumptions.
Cost Estimator
Adjust country, size and roof type. Working demo below.
Use this calculator ↓ROI & Payback
Model self-consumption, export credit and annual tariff change.
Battery Sizing
Size usable storage for evening loads and backup hours.
Panel Count
Translate roof area and panel wattage into feasible capacity.
Off-Grid Sizing
Balance loads, autonomy, battery reserve and worst-month sunlight.
Working calculator demo
Installed solar cost estimator
Use the controls to see an indicative solar-only range and simple payback scenario.
INDICATIVE INSTALLED RANGE
$20.0k–$28.0k
8.0 kW solar-only system in the United States, before incentives.
Panel count19 × 440 W
Annual generation10,249 kWh
Simple payback15.2–21.3 yrs
Method: country cost-per-watt range × selected size × roof complexity. Payback uses local rate, sunlight, 78% system yield, selected self-consumption and a conservative 35% value for exported energy. Battery, finance, tax, maintenance and future tariff changes are excluded.
Important:This calculator is for early-stage planning. Before buying, check roof condition, structural loading, shade, inverter limits, grid approval, warranty terms, applicable tax and current incentive rules.