Generating Electricity with a Cogeneration System
Cogeneration systems produce both heat and electrical energy and are based on the principle of combining electrical power generation with the production of usable heat.
In addition to generation of electricity, cogeneration systems also produce heat for hot water, space heating, or process heat for industry. A cogeneration system can reach an efficiency of 95%. Depending on its application, cogeneration systems come in various sizes. Small cogeneration systems up to 15kW power are called micro-combined heat and power, or “Micro-CHP systems”. Small-scale CHP systems can produce up to 50kW. Cogeneration systems for large buildings (residential developments, hospitals, commercial buildings) can generate up to 5MW of power.
Operating principles and applications
A cogeneration system is easily explained. A motor (combustion motor, steam motor, or Stirling engine) drives a generator which generates electricity. The motor also produces heat which is circulated through a heat exchanger. The heat can then be used for space heating or hot water. Cogeneration systems can produce process heat or, with an absorption heat pump can provide air conditioning. The generated electricity can be used immediately on site, or can be stored, or fed into the electrical grid.
Cogeneration systems can run on common fuels, such as diesel, oil, gas, biogas, biodiesel or wood pellets.