The concept of complementary decarbonisation of power generation from renewable energy sources and fossil fuels consists of their integration in one system. A technology network in the form of a CCU-combined power plant is proposed for the energy generation from fossil fuels by a coal power plant with CO2 recovery from the exhaust gases and a pyrolysis of natural gas to hydrogen and carbon as a basic technology. This technology network is completed by a reverse water-gas shift reaction for the conversion of the CO2 to CO, which will react with the hydrogen in a Fischer-Tropsch synthesis for synthetic diesel. The recovered energy from the exothermic Fischer-Tropsch synthesis meets the energy needs of CO2 scrubbing. The carbon from the pyrolysis can replace other fossil carbon or can be sequestered.