Combined heat and power plant

The combined heat and power plant (CHP) is an efficient and clean way to generate electrical and thermal energy, ideally the CHP is also operated at the place of the heat consumption. A combined heat and power plant basically consists of three components: Engine, generator and heat exchanger. The engine runs on fuel. A generator transforms the produced energy into electricity. The produced energy will be converted into electricity by the converter and the heat exchanger ensures that the waste heat that is generated can be used as heating energy.

Efficiency and overall efficiency of the CHP unite

The combined heat and power plant has a higher overall efficiency than the conventional combination of local heating and central power plant. This is primarily due to the fact that the waste heat from a CHP plant can be used immediately at the point of its generation. The ordinary CHP plant has an electrical output of between one kilowatt (kW) and several tens of megawatts (MW), below 50 kW it is a mini combined heat and power plant (mini CHP) and below 10 kW a micro CHP. Micro and mini CHP are used in hospitals, swimming pools and apartment as well as residential and business quarters.

The different operating modes

In general, different operating modes can be distinguished for the CHP unit. Ideally, the grid connection is covered so that overproduction can be added to the electricity grid to serve heating purposes or hot water production. If the power output depends on the local heat demand, then we speak of a heat controlled CHP. Therefor in a modular system individual units will be switched off or on depending on the heat demand. Another common operating mode is the electricity-controlled CHP unit. In this case, the power output depends on the power requirement.

Ecology and environment

The basic idea of an CHP unite is to convert efficiently every energy given. That's why unused electricity is fed into the public power grid for a small fee. The use of co generation plants enables lower carbon dioxide emissions and still achieves an impressive degree of utilization.