Heat pump and refrigeration cycle
The absorption cycle is similar to the compression cycle, but depends on the partial pressure of the refrigerant vapor. In the absorption system, the compressor is replaced by an absorber and a generator. The absorber dissolves the refrigerant in a suitable liquid and a dilute solution becomes a strong solution. In the generator, the temperature increases, which also increases the partial pressure of the refrigerant vapor released from the strong solution. The generator needs a heat source. This consumes a lot of energy unless waste heat is used.