Passive house
A passive house is a highly efficient building (residential or otherwise) that “passively” uses solar heat (sunshine) to drastically reduce the need for “active” heating and cooling, such as from an air conditioner and heating system.
A passive house is a highly efficient building (residential or otherwise) that “passively” uses solar heat (sunshine) to drastically reduce the need for “active” heating and cooling, such as from an air conditioner and heating system.
When heat is generated from renewable energy – such as biomass and solar thermal – one speaks of “renewable heat,” but the term can also encompass the recovery of waste heat for heating applications.
Geothermal energy is when heat from below the ground is pumped upwards.
Biomass usually means ethanol, biodiesel, biogas and wood pellets made from plants and waste products. It is the most versatile type of renewable energy as it can provide heat, energy and fuel.
Germany began building highly efficient passive houses in 1990. But although many buildings can now be renovated to fulfill very ambitious standards, a lot of progress still needs to be made towards increasing the energy efficiency of renovated buildings. To improve things, Germany has developed an Efficient Building Strategy.
Germany’s Renewable Energy Heat Act aims to increase the share of renewable heat to 14 percent by 2020. New building owners are obligated to get a certain share of their heat from renewable energy, and owners of old building get financial support for renovations.
Germany wants to get 25 percent of its power supply from cogeneration units by 2020 because cogeneration is much more efficient than separate power and heat generation. The Cogeneration Act therefore pays bonuses for cogeneration relative to system size.
When the waste heat of electricity generators is recovered for useful applications, we speak of the “cogeneration” of heat and power.