Initiative ELEKTRO+

Energy efficiency

Today’s essentials: electrical installation and energy efficiency

Today, the implementation of the statutory guidelines for energy efficiency plays an important part in the design and planning of the technical infrastructure of a building. Modern electrical installations, with their associated automatic systems controlling energy consumption, have a major influence on energy efficiency in houses and flats.

The DIN 18015 standard provides detailed information on energy efficiency for the planning of electrical systems in residential buildings.

Energy efficiency can be defined as optimal use of energy through the most efficient utilisation of the primary energy sources; exploiting wherever and whenever feasible renewable and environmentally friendly power generated from sun, wind or water.

Energy efficiency can be beneficially influenced via the electrical system in three ways:

  • through the use of modern, energy efficient electrical equipment, e.g. household appliances with high energy efficiency ratings (refrigerator);
  • through the optimal running of the electrical system and its appliances, e.g. avoiding the use of stand-by mode, activating lights via motion detectors, making use of intelligent lighting systems;
  • through the management of household electricity consumption with the aim of smoothing out the demand peaks in the load profile over twenty-four hours and utilising energy from renewable sources.

The last measure does not necessarily save energy. However, the redistribution of electricity consumption into so-called low demand periods allows more efficient economic and environmental use of network and generating capacities. This enables electricity generating capacity to be better planned and managed.

Detailed information supplied by an electronic electricity meter enables the electrical system to be run at maximum energy efficiency. These modern meters, using the latest technology, are now mandatory. To anticipate the fitting of such a meter the electrical system should fulfil the following criteria:

  • meter space (panels or cupboards) should be of adequate size to allow the installation and operation of a modern electronic meter with its associated communication technology;
  • electrical circuit distributors should have extra reserve connection points. This enables the subsequent installation of mechanisms to control the efficient operation of the electrical system and to minimise electricity consumption;
  • different usage zones should be given separate electrical circuits so that they can be controlled individually from a central point;
  • major household appliances with a high energy consumption should be assigned their own electrical circuit (this is already mandatory under the DIN 18015 standard);
  • provision should be made for the simple retrofitting of necessary measuring, controlling and switching systems, e.g. by the installation of electrical conduits;
  • and finally, automatically controlled electrical installations and appliances should be used in combination with intelligent building management technology to maximise energy efficiency.

Today’s effective and available technology enables the following domestic energy efficiency measures to be easily undertaken. They can be divided into three main areas of application:


  • Lights in halls and stairways activated by motion and occupancy detectors only switch on when someone is present.
  • Lights with dimmer switches save energy and prolong service life.
  • Energy efficient lights and bulbs reduce energy consumption while giving a comparable light output.


  • Individual room control, in combination with presence detectors and window sensors, regulate heating energy on a room-by-room basis according to demand.
  • Automatic sunshades or intelligent shutter and blind control allow warming but not overheating of the room. The same systems also stop cold entering or heat escaping (e.g. after dark) via the windows.

Household applicances and equipment

  • Sockets with switches allow appliances and equipment to be isolated from the mains electricity thus avoiding stand-by energy consumption.

By linking the above application areas through a building management technology system it is possible to implement further energy saving functions. (see standards: DIN 18015-2:2010-11 and DIN 18015-4:2010-11).

  • Vorschau

    Picture: Modern electronic electricity meter with associated communication technology.

  • Vorschau

    Picture: Lights activated by motion detectors.