Solar System Sizing Calculator
Free. No email required.
Figure out exactly how many modules, containers, and square meters you need to hit your target annual generation — calibrated to real regional yields.
Tip: 1 GWh = 1,000,000 kWh. Typical 500 kW commercial system produces ~700,000-900,000 kWh/yr.
JS-TOPCon 600W
We'll warn you if your target exceeds the space.
Your System Specification
Module pricing is current JUSTSOLAR factory-direct range. BOS + labor are indicative — varies heavily by country, tariffs, and EPC market. Get an exact quote below.
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Save your inputs + results for reference. Frank will follow up within 30 min if you want a firm quote.
We email your results once. No spam — your data goes only to Frank.
How This Calculator Works
Yield lookup
Regional yields come from PVGIS + Solargis historical averages, 10-year mean.
Mounting derating
Apply roof / tilt / orientation factor to get realistic yield for your installation.
Module sizing
Required kWp ÷ module watt → round up to next module. Container math follows MOQ.
This is a first-pass estimate. For financial-grade numbers, we run PVsyst/Solargis simulations with your specific site coordinates, shading, and weather file. Ask for a free simulation with your next quote.