The thermal efficiency of a cycle consisting of a combination of a Rankine power cycle and an absorption cycle has been examined with respect to upper cycle temperature and the solution used. Freon 22-DME. TEG and ammonia-NaSCN have been selected for comparison. An improvement of the Rankine cycle is expected. This improvement is higher for substances having a high latent heat. Although there is a strong dependence on the substance used in Rankine cycles, no considerable effect seems to exist in the combined cycle.