Industry

Decentralised Supply

Today's still largely centralised energy supply uses a power plant to supply energy to a large number of consumers in different geographical locations. However, a great deal of energy is lost while it is being transferred along very long routes to the consumer. Frequently, a decentralised energy supply would be more efficient. This concerns the supply of energy by small plants located in close proximity to the consumer. The plants are located directly where the energy is used.

The following advantages are associated with a decentralised energy supply:

• Efficient use of electricity and heat production
• Significantly lower transmission losses
• Independence
• Safe supply
• Operator directly influences the energy source
• Diversification of energy sources
• Job creation
• Regional accumulation of value
  

Centralised and decentralised energy supplies are not mutually exclusive. Both systems can co-exist and complement each other (integral energy supply).

Germany has recognised this fact and has been promoting the use of decentralised energy supply for years now. As a result of the support and promotion of renewable energies and the incentive to use combined heat and power, which was provided by the Renewable Energy Sources Act (Erneuerbare Energien Gesetz) and the combined Heat-Power Cogeneration Act (Kraft-Wärme-Kopplungsgesetz), Germany has had the foundation necessary to promote technologies in these areas since 2000.

Possibilities associated with a decentralised energy supply:

• Greater efficiency through the use of combined heat and power
• Use of renewable energies

First and foremost is the use of combined heat and power systems (CHP), which is characterised by the simultaneous generation and use of heat and power. In Germany, there are CHP systems in power classes from 0.8 kWel upwards for every application. Furthermore, expertise in this area continues to grow.

Different renewable energies can also work together. This is evident in the example of the German "combined renewable energy power plant".

The combined renewable energy power plant uses 36 wind, solar, biomass and hydraulic plants that are spread throughout Germany. Through joint control of small and decentralised plants, it is possible to provide a reliable source of electricity to meet requirements. The objective is to combine and benefit from the advantages associated with various renewable energies. Since the volume of electricity generated by wind turbines and solar heating systems depends on how much wind and sun is available, biogas power plants and hydraulic turbines are used to supply energy at times of peak demand. With a sophisticated control strategy, it is possible to achieve a fully decentralised energy supply through renewable energy alone.