Toolbox · Free

Size your solar water heater

With 4 answers, get the collector area, the tank volume and the real solar coverage of your hot water, calculated from the exact satellite sunshine data for your address, month by month.

Your household

A few simple details are enough. The advanced options are optional.

Property address

Sunshine taken from the PVGIS satellite data for this exact point.

Number of people in the household

Hot water consumption profile

How do you heat your water today?

These settings are optional: leave them as they are to use the defaults (flat-plate collectors, due south, tilted at 45°).

Collector type

Orientation

South 180° · azimuth

Drag the needle for a precise azimuth, or choose a quick orientation.

Tilt

45°

Collector tilt

0°15°30°45°60°

Target solar coverage · 60 %

30 %60 %90 %

Higher = more collectors, but a risk of overheating in summer.