Saving energy with a solar water heater

On average, an individual solar water heater (CESI) can cover 60% of domestic hot water needs (see this ADEME article). This means that some of the energy consumption associated with domestic hot water is avoided. This value is only used if the user does not know exactly how much energy they consume, and for the energy used to heat domestic hot water, i.e. electricity, gas, fuel oil and the heating network.