The performance of concentrating solar thermal power (CSTP) plants is limited by the availability of the sun and other parameters such as land and water. One probable solution of viable operation of CSTP plants in Kenya is the hybridization of the CSTP plants with biogas backup systems to improve their performance. Biogas can be generated using dairy manure and the same can be used for hybridization. The paper reports on the performance difference between wet and dry cooled parabolic trough CSTP plants. It also reports on the economic assessment of a dairy farm and the hybridisation of parabolic trough CSTP plant with biogas waste heat. In the CSTP-biogas modelled, the waste heat from the biogas plant is used for reheating the heat transfer fluid (HTF) in the high pressure boiler of the parabolic trough Rankine cycle.