Zero-energy building

Zero Energy House is an energy standard for buildings, which is reached when the external power occupation of the building throughout the year by its own energy gain (eg through solar systems, etc.) is outweighed. Technically, the zero-energy house is often a continuation of the idea of the passive house, which is equipped in addition to the passive heat recovery with solar installations for hot water and electricity supplies and external power balances during the year. If more power is generated than consumed the house itself, it is called a plus-energy house. Building, which, moreover, no external power relate and take care of himself called energy independent.

This does not include the zero -energy standard is the energy that is needed to build the house. For example, an energy payback time of about 12 years is indicated for the completed in 1992 solar house in Freiburg, which means that it takes about 12 years for the energy that was used in the construction of the house, was saved by the special design of the zero -energy house again. Energy which is consumed in the production, transport, installation and of the disposal of the materials used, is also referred to as " gray energy ".

According to the Industry Committee of the European Parliament, all buildings that are built after December 31, 2018 produce their energy consumption on site.

Components

Key elements of a zero-energy house are

• Large windows to the south, which are also in the winter, when the sun is low, unshaded
• A low A / V ratio ( ratio of surface to volume of enclosed )
• Exterior building surfaces ( walls, roof, windows, doors) with low heat transfer coefficient ( = heat transfer coefficient, U - value, formerly k-value)
• (also called wind tightness) a high degree of air tightness

Examples

The world's first zero-energy hotel was opened in November 2009 in the 15th district of Vienna. The energy can be produced by photovoltaic and solar panels, vertical wind turbines and heat pumps.

Is currently being built on the site of a former secret service used U.S. military base in Bad Aibling the zero energy city Mietraching.

Several hundred building projects worldwide since the early 1990s has been realized and its objective was to achieve a balanced energy or emission annual balance sheet. Many of these projects have been collected in the research program "Towards Net Zero Energy Solar Buildings".