In many areas of our daily life, we have grown accustomed to think in terms of open systems. We use commodities and purchase them in shops, and after their consumption lifetime, we dispose of them. Wastes and residues are then deposited, off our conscious perception. This kind of social and economic activity regards our environment as an open system, ready to proliferate services and absorb used products.
Thinking in open systems increases specialization and responsibility only for single parts of the integrated economic and ecological life-cycle processes. For a sustainable development, it is necessary to have a paradigm shift toward thinking in closed systems. Our planet is a closed biospheric and atmospheric system that we have to consider in our daily routine activities.
It seems far too complicated to cope with the multitude of variables in this global system. However, smaller subsystems can be manageable, and the combined consideration of closed subsystems makes it feasible to treat the total system in a sustainable way.
In this book, we discuss approaches to a future-oriented mobility and transportation system. Renewable energies are fundamental to sustainable mobility for their ecological assets and their contribution to a stable world climate. The idea of using renewable energies for fuel production also derives from regarding the mobility sector as a closed system within the global atmosphere.
The value of renewable fuels becomes clearer when we draw parallels to the electric power sector. Residents of off-grid, stand-alone solar home systems esteem the services provided by their wind and solar power generators. This form of electricity is so expensive that it is used in the most efficient way conceivable. Designing solar homes urges one to abandon conventional approaches of house heating and electrification design. The use of renewable