Energy-saving homes

With a sense of environmental protection plus the scarcity of resources on Earth, architects in Germany are competing to design the most energy-efficient houses.

At first glance, the Gartenstadt apartment complex in Mannheim city looks no different from normal apartments but they attract attention thanks to the special features inside. Built from the early 1930s according to classical architecture, the complex consists of 24 2-floor apartments with a width of 1,300m ² , after being comprehensively upgraded, it has become a model of energy-efficient housing. It is also called a ' 3-liter house ', meaning for heating,

' Passive houses ' will help homeowners save a lot of energy in the winter. (Photo: Passivhaustagung.de)

people only need 3 liters of oil / m ² / year. This is the most energy efficient ever since even new homes built with energy saving standards must consume twice as much fuel. The residence is a pilot project of GBG Construction Company with technical assistance from Stuttgart University.

Under German construction laws, buildings must be equipped with insulation of a minimum thickness of 12cm, but with Gartenstadt apartments, GBG uses 20cm thick insulation. The ceiling is designed to be 4 times thicker than standard and the windows are also carefully processed. When the building is complete, energy-saving properties are carefully tested by reducing the air pressure inside the house to match the external pressure, then checking the airflow rate. The experiment showed that the temperature after the ' permeate ' air through the wall decreased significantly.

In Lower Saxony, the construction company Viebrock is constructing houses that only consume 2 liters of oil / m ² / year. In 2006, two-thirds of 1,300 buildings built by Viebrock were energy-saving. And the ' passive houses ' were born with the goal of consuming less than 1.5 liters of oil / m ² / year. The name ' passive home ' comes from the fact that this type of house almost doesn't need any heating system, because it only needs heat from the small appliances plus the body temperature of the insiders. house is enough. With an internal heat sink, the automatic ventilation system will make the rooms more airy. Currently, the term ' passive house ' is being used widely by construction entrepreneurs.

The first passive house was built in 1991 by Darmstadt by design engineer Wolfgang Feist. By 1999, he began to build houses for big families, followed by fuel-efficient apartment buildings. The world's largest passive office building named ' Energon ' was built in Ulm in 2002. Currently the world has more than 6,000 passive buildings, including apartments, office buildings, factories and medical centers. and schools mainly in Germany, Austria and Switzerland.

Like ' passive houses ', the abbreviations ' KfW 60 ' and ' KfW 40 ' are also popular terms used to refer to homes that use no more than 60 or 40 kilowatt hours / m2 / year. Germany is encouraging people to use energy efficiently by providing financial support to those who want to build new homes, households can apply for loans at the government's KfW bank.

At the same time, Germany is also aiming to build ' positive energy ' houses - consuming about 11-14 kilowatt hours / m2 / year. Not only without energy consumption, the ' active energy ' house by architect Rolf Disch in Freiburg also designed to generate electricity through a solar panel installed on the roof. The amount of unused electricity will be added to the line system. Disch claims that homeowners can increase their monthly income thanks to the electricity generated by the house. This income may not be too high but certainly useful when fuel prices are increasing.

THANH TRUC