Why is a change in the energy supply necessary?
Over 80% of the global supply of energy nowadays is based on the use of fossil and nuclear energy sources1. However, it is commonly known that following this path of energy supply is affiliated with considerable problems, which can be summarized in two groups:
- Finiteness of fossil and nuclear energy sources: finite natural deposits have to be exploited for both fossil energy and nuclear energy sources. However, sources of fossil energy from biomass are regenerated, but this process lasts millions of years and is not relevant from a human perspective. Exactly when sources of fossil and nuclear energy decline is dependent on how much is consumed, the discovery of new natural mineral deposits and the development of new materials handling technology. In general, it can be nonetheless assumed that, based on existing consumption, stocks of most fossil and nuclear sources of energy will be exhausted by the end of this century.
- Negative effects on the environment and living space: considerable negative effects and hazards on the environment are connected to the use of fossil and nuclear energy sources. Climate change as a consequence of a anthropogenic greenhouse gas effect, which can be to a great extent related to the burning of fossil energy sources, is one of those effects. The risk of nuclear disasters and the continuing unsolved problem of storage of nuclear waste are two more of the problems associated with this situation.
The existing problems make certain strategic solutions necessary.
 Share of primary energy consumption, based on 2006; Wesselak V. & Schabbach T. Regenerative Energietechnik Springer Berlin / Heidelberg 2009, S. 5