Importance of building energy conservation

The energy resources in earth are limited. The contradiction between energy demand and supply directly affects the development of productivity and social stability.

Energy consumption not only consumes natural resources, but also produces a large number of harmful substances. It is well known that carbon dioxide warms the atmosphere, intensifies the earth's greenhouse effect, causes environmental protection problems and affects human survival.

Economically, the cost of energy production and energy consumption is rising. Countries, collectives and individuals are more and more aware of the seriousness of the problem and affect their vital interests.Therefore, energy conservation and effective use of energy have become one of the urgent issues and problems that should be solved in the whole world.

The meaning of reducing building energy consumption as much as possible is the concretization of the significance of energy conservation:

    ▪    It can reduce energy consumption.

    ▪    It can reduce the emission of harmful gases and carbon dioxide.

    ▪    It can reduce the operating cost of buildings.

According to statistics, the energy consumption of buildings accounts for 30% ~ 40% of the global energy consumption. In Europe, due to high latitude and cold climate (heating), 40% of its energy consumption is written into the building account. In Asia and other regions, with the improvement of people's requirements for living comfort, the energy consumption of buildings is rising. This energy consumption layer of buildings is generally recognized as having the greatest energy-saving potential. Building energy conservation has become the top priority to solve the global energy conservation problem. It is an area with sufficient space to develop and implement effective measures, which will bring great economic and social benefits and improve life comfort.

The building energy conversation in Germany is effective

Germany carried out building energy-saving activities very early and effective. The building energy-saving system and technology are in a leading position in Europe and even the world. According to the statistics of the German Federal Ministry of economy and labor, from 1991 to 2001, Germany's GDP increased by nearly 16%, but the total energy consumption decreased. The main results of energy conservation and effective use of energy came from energy-saving buildings and supporting facilities of energy-saving buildings.

In 1978, the standard of building heating energy consumption in Germany was about 200 per square meter per kilowatt hour per year. In 2002, the index decreased by about 63%. The standard index published in 2012 continued to decline by at least 50%, which was about 35 per square meter per kilowatt hour per year. At present, the revised 2014 version will reduce the heating energy consumption of passive buildings to 15 per square meter per kilowatt hour per year, basically reaching the "zero energy consumption" of buildings.

Energy conservation and environmental protection are closely linked, which is energy conservation under the guidance of the concept of environmental protection. The emissions of greenhouse gas in Germany decreased by nearly 19% from 1994 to 2006 and continued to decline by 21% from 2008 to 2012. According to the statistics of the German Federal Ministry of environmental protection, the use of renewable energy accounted for 14% of the total power generation in 2007 and increased to 14.8% in 2008. The continuous goal is to increase to 30% by 2020 and 50% by 2050. This will directly contribute to the goal of reducing greenhouse gas emissions. The experience of Germany tells us that building energy conservation has great potential.

The research and application direction of building energy efficiency in Germany and its implementation strategy

The research and application of building energy-saving technology in Germany can be summarized as follows:

  i.    Careful and rigorous quantitative evaluation technology for building quality and energy-saving performance, including the calculation and measurement of energy consumption of various parts of the building, the calculation and measurement of building thermal insulation performance, and the calculation and measurement of the efficiency of mechanical and electrical HVAC facilities of the building;

    ii.     Carefully design and adjust the building layout and building enclosure (door and window top wall) to make full use of natural climate conditions and reduce building energy consumption;

    iii.    Improve building equipment and equipment layout, improve efficiency and reduce energy consumption;

    iv.    Encourage the use of renewable pollution-free energy, such as solar energy, wind energy, hydro energy, geothermal energy and biochemical energy, so as to reduce the consumption of expendable energy by buildings, protect earth resources and reduce environmental pollution; 

    v.     Use waste heat to recover residual energy and reduce the energy demand of buildings; 

    vi.    Develop and use new low-energy building materials, so that the manufacturing and recycling process of these materials is green and low energy consumption, and the good thermal performance of the materials themselves can reduce the energy consumption of buildings.

In order to achieve the purpose of building energy conservation, a series of building energy conservation strategies have been formed in Germany on the basis of extensive discussion between the people and the government. The key aspects are as follows:

  Develop regulations, codes and standards 

        -    Draft regulations, codes and standards for building energy conservation

        -    Supervise the implementation of specifications

        -    Regularly and irregularly revise regulations and specifications to gradually improve energy-saving indicators

  Provide information, advice and training

        -    Make quantitative marks and certificates for building energy consumption

        -    The consulting of building energy conservation

        -    The training about building energy conservation

  Linked to economic benefits and rewards

        -    Discussion and implementation of building energy use-tax

        -    Other economic measures to promote building energy conservation

        -    Put forward reconstruction requirements and implementation measures for old buildings that do not meet the energy-saving requirements

        -    Propose abolishment requirements and implementation measures for old equipment that does not meet the energy-saving requirements

  Propagate and public opinion on building energy conservation is also an important additional strategy

Notes: BEE is the abbreviation for Building Energy Efficiency.