Combined heat, power and cooling
The combined heat and power ( CHP ) is an extension of the combined heat and power (CHP): The heat generated by a block-type thermal power station , a solar thermal system or a geothermal system is used to operate an absorption chiller or adsorption chiller for air conditioning. The cold transport medium is usually treated water with a flow temperature of approx. 6 ° C. The cold generation can be done in summer in addition to the heat generation in winter or in warmer countries in year-round operation. In some cities, e.g. B. Chemnitz and Vienna , CHPP is also operated on a large scale by feeding large absorption chillers with heat from the existing district heating network. If the cooling takes place centrally, it is distributed to the customers via a district cooling network . Cold storage systems are usually integrated into such networks in order to be able to cover peak loads.
Although the absorption refrigeration machine, in contrast to an electrically operated compression refrigeration machine, requires higher investment costs and is more difficult to integrate due to the larger construction volumes, the CHPP has its advantages. In summer, not only does the hot water preparation serve as a heat sink for the CHPP, but also the evaporator of the absorption chiller. As a result, the number of annual operating hours of the CHP plant can be increased significantly and its profitability improved. In comparison to CHP and the additional operation of compression refrigeration machines, CHPP uses the primary energy sources more efficiently and thus reduces emissions.