Energy

Both calculators in this category answer the same question — is this investment worth it for me? — for two different sources: solar panels and a heat pump. Each exists for eight countries, because electricity prices, grants and climate differ enough that a single shared calculation would be meaningless.

The solar calculator takes the system size in kWp, your consumption and your electricity price, and works out annual generation, savings and the payback period. It can compare a system with and without a battery, and include a grant if you qualify for one.

The heat pump calculator starts a step earlier: from the floor area and the state of the building it estimates heat loss and the output needed in kW, and only then compares annual running costs against gas, pellets or electric heating. If running a heat pump comes out more expensive than your current source, the calculator says so — not every house is ready for one, and an uninsulated building is exactly that case.