This thesis deals with the possibility to use other than hydrocarbon reservoirs for power generation with various technologies. Fact is that there are reservoirs that are not really worthy for hydrocarbon production and the idea rises to use them to generate electricity. The aim of this thesis is the further consideration of these technologies in terms of their usefulness and the description of a possible process cycle. We inject supercritical CO2 into the reservoir to produce in our case a gaseous CO2-methane mixture. Supercritical CO2 has certain advantages over water because of its special physical state, which is between liquid and gaseous. The produced mixture can then further be used by a variety of different energy cycles. In this case, we relax the mixture first in an expander to reduce the high pressure while producing already a part of our desired electrical energy. However, it is important to ensure that the medium doesn’t get too cool. We now separate our mixture. The gaseous CO2 is then transformed again into its supercritical state by using a compressor, and if necessary a heat exchanger, so the circuit can be closed. The methane can then be used with the help of a combined cycle plant for the mean power generation. Combined cycle power plants consist basically of a gas turbine and a steam turbine process, which uses the exhaust gas temperatures of the gas turbine through a heat exchanger. Afterwards the remaining exhaust gases may be further used in a thermal power plant. In this thesis, you can find accurate data and facts about the significance and magnitude of the potential energy to be recovered on a specific example. The amount of potential energy and the process flow may differ depending on the input parameters. The relatively high amount of power that can be generated depends of course on the input parameters. Although the investment costs will be slightly higher, since most machine components must be tailored according to the parameters.