I. Fossil fuel fired CHP

Cogeneration units can run on a variety of fuels, all of which offer unique environmental benefits compared to the conventional technology alternatives. Today, Natural gas is the most widely used fuel in CHPs with a share of 39.4% in Europe.

Natural gas fuelled application:
Natural gas benefits from several factors, such as its high heating value, an attractive fuel cost and being available in many locations. In addition, it is a cleaner fuel with low carbon content. It produces 40 to 50% less CO2, than coal fired CHP. These characteristics make natural gas fuel of choice in Cogeneration systems.

Heating oil
Heating oil has a high energy content per volume and is very easy to transport and store.

II. Renewable fuels

In Europe, 11% of electricity produced by CHPs comes from Renewable fuels. Cogeneration fuelled by renewable energy combines the advantages of environmental sustainability plus maximum energy efficiency.

Biomass for heat production
Combustion of solid biomass (wood derived) for heat production is the main CHP bioenergy route in the world, with a constant drive for improved efficiency and reduced pollutant emissions. Several systems can be considered, depending on the size. Small-scale heating systems for households typically use firewood or pellets. Medium-scale users typically burn wood chips in grate boilers while large-scale boilers are able to burn a larger variety of fuels, including wood waste and refuse-derived fuel. Heat can also be produced on a medium or large scale through cogeneration which provides heat for industrial processes in the form of steam and can supply district heat networks.

Biogas fuelled applications:
Pulled by EU legislation, biogas production (either via conversion of bioenergy or capture and upgrade or “waste”) is growing. Many small-medium sized CHP are now operating on biogas.
Biogas produces no net carbon emissions.

Biodiesel fuelled applications:
Today the biodiesel fuel is made from biomass such as vegetable oils (rapeseed oil in several part of Europe). As it seems biodiesel would be price competitive in the future.

Geothermal: A growing area of interest is focusing on the use of heat from geothermal source to be coupled to a CHP unit. Geothermal is recognised as being pivotal contributor for Europe’s energy mix now and in the future.