Cumulated energy expenditures are determined for two non-regenerative and for three regenerative power station types and are used for the calculation of energetic characteristic values harvest factor and amortization time, as well as a quality factor in respect of the CO2-production. The results indicate - despite partly very provisional figures - clear advantages of the ＇＇established＇＇ coal and nuclear power stations compared to all the other investigated power station types. Wind power stations and solar collectors for hot-water supply are in a kind of intermediate position, whilst photo-voltaic solar power stations (based on mono-crystalline silicon cells) end up by far the worst. At the present state of art and under our climatic conditions, their energy balance is only approximately at an equilibrium, i.e. they generate during their total life duration approximately just as much energy as is required for their production, their operation and the following demolition including disposal.