Energy efficiency

from Wikipedia, the free encyclopedia

The energy efficiency is the ratio of services, goods or energy output (output) to the input energy (input) (see. Energy Efficiency Directive 2012/27 / EU ). Energy efficiency is understood to mean the rational use of energy . Optimized processes are intended to minimize “the quantitative and qualitative losses that arise in the individual conversion , transport and storage of energy ”, “in order to achieve a given (energetic) benefit with decreasing primary or final energy use ”.

Legal norms

The EU energy label provides information about the energy efficiency of household appliances

Energy saving

With the EC Directive 2002/91 / EC Energy Performance of Buildings Directive (EPBD) , the term energy efficiency came into common German usage.

This guideline was implemented in German law with the Energy Saving Act (EnEG) and, based on it, with the Energy Saving Ordinance (EnEV), in which in §20 the improvement of the energetic properties leads to improved energy efficiency. The final energy requirement is the measure of energy efficiency. A distinction is made between overall energy efficiency, in which, in addition to the final energy requirement, the upstream chain (exploration, production, distribution, conversion) of the energy sources used (e.g. heating oil, gas, electricity, renewable energies, etc.) is taken into account. The energy efficiency can be determined and documented in the energy certificate using the pre-standard DIN V 18599 Energy assessment of buildings .

The Directive 2006/32 / EC on energy end-use efficiency and energy services ( Energy Service Directive ESD ) contains indicative targets and promotes the market for energy services as well as the provision of other energy efficiency measures to end consumers.

The new Directive 2012/27 / EU (Energy Efficiency Directive) of October 25, 2012, among other things, stipulates mandatory energy savings in order to achieve the EU target of 20% higher energy efficiency compared to 2008. Germany failed to transpose the directive into national law on time. In August 2014 the EU Commission initiated infringement proceedings.

Waste recycling

According to the EU Waste Framework Directive , the energy efficiency of a waste incineration plant decides whether it is a waste recovery process , namely an energetic recovery or a disposal process. According to the so-called waste hierarchy, recycling takes precedence over disposal with corresponding consequences, for example for the approval of plants or the criminal liability of waste disposal.


Many industrial processes require large amounts of heat and mechanical energy. Most of these are provided by fuel and electricity. So-called secondary fuels are used in some areas (e.g. cement production ) . Due to the diversity of industrial processes, there are numerous possibilities for increasing efficiency. Often these are specially adapted processes and technologies. Improved boilers and burners can operate at higher temperatures while burning less fuel. This makes them more efficient with lower pollutant emissions .

Conventional power generation by steam power plants , in which the resulting heat escapes as waste heat, typically converts a good 40% to ideally 60% ( CCGT ) of the energy used into electricity. Through the combined use of electricity ( combined heat and power ), combined efficiencies of over 90% can be achieved. In industry, an average of approx. 0.4 is achieved, which shows the further potential to expand process heat generation through more exergetically efficient CHP.

Of the fuels that American industrial companies burn, over 45% (as of around 2005) are used to generate steam. According to a leaflet from the Washington Environmental and Energy Study Institute, typical operations can reduce the energy required for this by 20% by insulating the piping for steam and condensate , closing leaks in the steam lines and using steam traps .

Many electric motors run at constant speed, but with an electronic speed control the energy output of the motor can be adapted to the respective load. Depending on the type of engine used, savings of 3 to 60% can be achieved. Electric motors from 0.75 kW to 375 kW have been divided internationally into energy efficiency classes from IE1 to IE4 since 2009 . As a forerunner regulation, a division into classes EFF3 to EFF1 has applied in Europe since 1998.

The industry uses a wide variety of pumps and compressors. Their efficiency depends on various factors; often better process control and maintenance can improve efficiency. Compressors are commonly used to generate compressed air for tools, sandblasters, sprayers, and others. The energy efficiency of compressed air systems can be improved by 20 to 50% by installing speed controllers and using preventive maintenance to find and seal leaks .

The German Energy Efficiency Initiative (DENEFF) presented the first energy efficiency industry report in May 2013. To this end, she examined market structures, figures and trends in the energy efficiency industry. The market for energy efficiency generated a total turnover of 146 billion euros in 2012. This is an increase of 16 percent compared to the previous year. The number of employees increased by 10 percent over the same period to around 800,000. The report is based on a survey of 63 companies from various fields such as mechanical engineering, building energy consulting, building materials, banks and household appliances as well as on existing studies and statistics. So far, there has been no such comprehensive overview of market data, developments and sentiments among companies whose business is energy saving.

The Institute for Energy Efficiency in Production (EEP) at the University of Stuttgart has been publishing the Energy Efficiency Index (EEI ) since 2013 in cooperation with Fraunhofer IPA, the Federation of German Industries (BDI), the German Energy Agency (dena) and TÜV Rheinland ). It is a semi-annual survey that asks companies from 26 different branches of the economy (as of: summer survey 2016) on various aspects of energy efficiency. A total of 637 companies took part in the survey for summer 2016.

Potential and political discussion

Improved energy efficiency is one of the possible ways to save energy. Energy saving is the broader term because it includes other measures that reduce energy consumption, such as behavioral changes . For example, even without improved efficiency, it is possible to save energy by heating a room less or by driving less in winter.

According to a study by the International Energy Agency (IEA), the world's energy consumption can be reduced by 17 to 33% by 2050 through improved energy efficiency in buildings , transport and industrial processes .

In Germany, according to a study by the German Business Initiative for Energy Efficiency (DENEFF), efficiency measures can reduce annual electricity consumption by 68.3 billion kilowatt hours by 2020, which roughly corresponds to the annual production of ten nuclear power plants .

According to the EU Commission, 90% of all apartments in the EU are not energy efficient.

A study by Prognos and the Institute for Electrical Systems and Energy Economics Aachen (IAEW) comes to the conclusion that the energy transition can be made several billion euros cheaper by 2035 if the incentives for saving electricity were increased. A reduction in electricity consumption by 10 to 35 percent compared to the planned development will lower costs by 10 to 20 billion euros in 2035. This could significantly reduce the electricity bill, and depending on the increase in efficiency, the need for expansion in the high-voltage network would decrease from around 8,500 kilometers to 1,750 to 5,000 kilometers by 2050.

The implementation of the political goals is slow. The goal declared in the course of the energy transition of reducing energy consumption by 20% by 2020 compared to 2008 will probably be clearly missed, as the Federal Ministry of Economics stated in the National Action Plan on Energy Efficiency ( s ) (NAPE) at the end of 2014. According to a meta-analysis by the Renewable Energy Agency, in which 14 scientific studies were evaluated, only a reduction of 10-15% is achieved with existing measures. The Federal Association for Renewable Energy called for efforts in the field of renewable heat and mobility to be accelerated.

As early as September 2013, 21 experts called on politicians to adopt a more consistent efficiency policy. “Without a new energy saving policy, the energy transition would become more expensive, slower and more difficult”, because: “The lower the energy requirement, the lower the need for new generation, network and storage capacities.” For years it has been known that over 60 percent across Germany of final energy consumption could be economically and sustainably saved, more than half of that in the next 20 years alone. In order to limit the costs of the energy transition to a reasonable level, the authors therefore urge an integrated energy efficiency policy for a balanced “energy balance”, in which the expansion of an environmentally friendly supply structure goes hand in hand with the reduction in energy demand.

According to the DIHK , savings targets are superfluous and the reduction of electricity consumption is not necessary for climate policy.

International cooperation

Initiated by the Eastern Committee of German Business , an energy efficiency partnership was concluded for the first time in 2013 between the German city of Delitzsch and the Ukrainian city of Schowkwa . In the context of national and international comparisons, Delitzsch is one of the communal pacemakers for sustainable urban development and energy efficiency. In addition to the local political and civic engagement in the city of Delitzsch, the project partners include the Federal Ministry for Research and Development , the Institute for Infrastructure and Resource Management at the University of Leipzig and the Research Center Jülich.

Efficiency promotion in Germany

Since the 18th legislative period of the federal government (2013–2017), reducing energy consumption through greater energy efficiency has been the key pillar of the energy transition, alongside the expansion of renewable energy.

The core idea behind the Efficiency First principle: The cleanest energy is that which is not generated, transported or consumed in the first place. On July 1, 2015, the Federal Government decided, as part of its Climate Protection 2020 action program, that by 2020 an improvement in energy efficiency (through an expansion of the National Action Plan on Energy Efficiency, NAPE) should reduce emissions of between 25 and 30 million tons of CO 2 (without Transport sector). For this purpose, the BMWi is making a total of around 17 billion euros available through corresponding funding programs by the end of the second decade (2020).

Promoting efficiency in Switzerland

As a counter-proposal to a popular initiative to phase out nuclear power , the following constitutional provision was introduced in Switzerland as early as the 1980s (Art. 89, Paragraph 3): “The federal government issues regulations on the energy consumption of systems, vehicles and devices. It promotes the development of energy technologies, especially in the field of energy saving ”. However, the provision has only been implemented selectively so far.

This instruction was also communicated to the cantons in the Energy Act of 1998 (EnG, Art. 9, Para. 1) "The cantons create favorable framework conditions for the economical and rational use of energy and the use of renewable energies within the framework of their legislation."

See also : 2000 watt society


  • Jürgen Dispan: Greentech in mechanical and plant engineering in Baden-Württemberg. Potential in the future fields of energy efficiency, renewable energies, electric mobility. (= IMU information service. Issue 1-2011). Stuttgart 2011. (PDF; 1.3 MB)
  • Matthias Günther: Energy efficiency through renewable energies. Possibilities, potentials, systems. Wiesbaden 2015, ISBN 978-3-658-06753-3 .
  • Peter Hennicke , Susanne Bodach: Energy Revolution: Increased Efficiency and Renewable Energies as a New Global Challenge. Munich 2010, ISBN 978-3-86581-205-6 .
  • Jens Hesselbach: Energy and climate efficient production. Basics, guidelines and practical examples. Wiesbaden 2012, ISBN 978-3-8348-0448-8 .
  • Martin Pehnt (ed.): Energy efficiency: A teaching and manual. Springer, Berlin 2010, ISBN 978-3-642-14250-5 .
  • B. Steinmüller: Reducing Energy by a Factor of 10 - Promoting Energy Efficient Sustainable Housing in the Western World . Center for Sustainability Management (CSM), Lüneburg 2008 (online)
  • Miriam Vollmer: Sustainability as a benchmark for the energy efficiency requirement - An investigation into Section 5 Paragraph 1, Sentence 1 No. 4 BImSchG. Kovač, Hamburg 2009, ISBN 978-3-8300-4123-8 .
  • Ernst Ulrich von Weizsäcker , Amory Lovins , Hunter Lovins , Factor Four. Twice the prosperity - halve the consumption of nature . Munich 1997, ISBN 3-426-77286-8 .
  • Ernst Ulrich von Weizsäcker, Karlson Hargroves, Michael Smith: Factor Five. The formula for sustainable growth. Munich 2012, ISBN 978-3-426-40022-7 .
  • Franz Wosnitza, Hans Gerd Hilgers: Energy efficiency and energy management. Vieweg + Teubner, Wiesbaden 2012, ISBN 978-3-8348-1941-3 .

See also

Web links

Wiktionary: Energy efficiency  - explanations of meanings, word origins, synonyms, translations





Individual evidence

  1. Energy Efficiency Directive 2012/27 / EU of October 25, 2012.
  2. Viktor Wesselak , Thomas Schabbach , Thomas Link, Joachim Fischer: Regenerative Energietechnik. Berlin / Heidelberg 2013, p. 35.
  3. Wirtschaftswoche: EU punishes Germany for wasting energy , August 13, 2014.
  4. on waste hierarchy s. Article 4, on subordinate disposal, Article 12 of Directive 2008/98 / EC of the European Parliament and of the Council of 19 November 2008 on waste ; To distinguish between process R 1 (main use as fuel / energy generation) according to Annex II to disposal process D 10 or 11 (Annex I), see footnote 8 with the calculation formula and differentiation according to the operating license of the waste incineration plant
  5. Tina Baten, Hans-Georg Buttermann, Thomas Nieder: Combined Heat and Power 2008 to 2016 - Influence of the Balance Boundary, Energiewirtschaftliche Tagesfragen, 67th year (2017), No. 12
  6. a b c Environmental and Energy Study Institute: Industrial Energy Efficiency. Using new technologies to reduce energy use in industry and manufacturing. Washington DC, May 2006.
  7. DENEFF: Industry Monitor Energy Efficiency 2013 .
  8. ^ Institute for Energy Efficiency in Production EEP, University of Stuttgart: The Energy Efficiency Index of German Industry. Retrieved July 26, 2016 .
  9. Hanspeter Guggenbühl: Why the efficiency in road traffic has decreased. In: . October 25, 2019, accessed November 18, 2019 .
  10. IEA: Scenarios and strategies up to 2050 (PDF; 926 kB), Energy Technology Perspectives 2006.
  11. DENEFF: 10-point immediate program , April 7, 2011.
  12. EU Commission: Starting signal for the European Energy Union. Press release from February 4, 2015.
  13. Agora Energiewende : More energy efficiency makes the energy transition significantly cheaper ( Memento from March 31, 2014 in the Internet Archive ), March 2014.
  14. BMWi: National Action Plan on Energy Efficiency , PDF, 2014.
  15. Research radar Energiewende: Development of energy consumption in Germany. 2014.
  16. BEE: Strong impetus for the climate and the economy only with renewables. Press release, December 2, 2014.
  17. DENEFF: Energy experts urge politics to halve energy waste . News from September 5, 2013.
  18. BMWi Energiewende direct: Do we need a binding target triad for greenhouse gas reduction, expansion of renewable energies and energy efficiency? , August 5, 2014.
  19. Eastern Committee of German Business: "Energy Efficiency Week" in Zhovkva , September 30, 2013.
  20. Manfred Wilde (ed.): The sustainable city. Future-proof communal resource management. de Gruyter Oldenbourg, Munich 2014, ISBN 978-3-11-035382-2 .
  21. ^ Coalition agreement between CDU, CSU and SPD, 18th legislative period , PDF, p. 51.
  22. BMUB: Action Program Climate Protection 2020  ( page no longer available , search in web archives ), PDF, December 2014.@1@ 2Template: Toter Link /
  23. BMWi: Energy Efficiency Funding Strategy , PDF, May 2017.