How to spare energy when the price of energy continuously raises? When buying a fridge, I paid special attention to how a thicker thermal isolation layer reduces the energy consumption. A higher purchase price will be payed back in energy savings, storage time in power failure, and stillness.
Passive houses resemble fridges. In building them special attention has to be paid on the thermal isolation, heat recovery ventilation and quality. The house warms up by the sun, household appliances and people. A modest warming system protects in case of a really cold weather.
Building a passive house costs 5-10 % more, but will the investment pay back? Heat is released yearly 25 kWh/m², in an old house 150 kWh/m². For a 200 m² and 1000 €/m² house, the energy price of 8 c/kWh results in the payback period of less than 10 years.
