The average Czech household utilizes some 60% of its total energy requirement on heating. This energy gradually escapes to the outside via the building construction (external walls, roof and roof construction, windows and doors). It is important to state that the total removal of such energy loss is almost impossible but can be significantly reduced via insulation.
The energy consumption for heating in older houses is in the region of 200 kWh/m2 and in low energy houses in the region of 50 kWh/m2. Insulation on average saves approximately 50% energy and in the case of low energy or passive houses this can increase to some 80%. Investments made in insulation can via lower energy bills for gas or electricity show a quick return on investment.
Zelená úsporám supports investments in energy savings via insulation with a number of hurdles depending on the percentage of energy savings reached.

A passive house is a building with a comfortable internal environment in both the summer and winter and with such a small heating requirement that a typical heating system is not necessary. The energy requirement of a passive house does not exceed 15 kWh/m2/rok.
In comparison with a typical house the heating requirement is reduced by some 80%. Passive buildings require also the minimum energy consumption in relation to other energy using applications in the home such as electricity for domestic appliances. The final energy requirement for heating, ventilation, hot water and electricity will be in the region of 42kWh/m2/rok.
Zelena úsporám supports investments into passive housing along with support also for the house design:

Throw away your old non-ecological coal boiler or stop heating with electricity and start using a low emission biomass replacement such as wood boiler, wooden briquettes, pellets or wood chips. This is not the only option however, a Heat Pump is another possibility which works on the basis of electricity but principally takes its energy either from heat in the ground or heat from the air.