About this calculator

EU rule: 1 m² flat-plate or 0.8 m² evacuated tube per person, with a 50–80 L cylinder per m². Annual yield in Central Europe ~400 kWh/m²; Mediterranean ~600 kWh/m².

Frequently asked questions

What does the Solar Thermal Hot Water Sizing do?

Flat-plate collector area for a household's hot water demand (EU). EU rule: 1 m² flat-plate or 0.8 m² evacuated tube per person, with a 50–80 L cylinder per m². Annual yield in Central Europe ~400 kWh/m²; Mediterranean ~600 kWh/m².

Is the Solar Thermal Hot Water Sizing free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Solar Thermal Hot Water Sizing?

Results are calculated in real time using industry-standard formulas. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified solar thermal professional before committing to a purchase or a job.

What inputs does the Solar Thermal Hot Water Sizing need?

Enter values for: People in household, Collector, Yield kWh/m²/yr. Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Solar Thermal Hot Water Sizing on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.