Energy converting system

Bacteriorhodopsin is the protein component of the purple membrane it resembles the visual pigment rhodopsin and acts as a light-energy converting system. It is part of a simple photosynthetic system in halobacteria that live in the Bay area near San Francisco and cause its characteristic orange-red color. Oesterhelt, by then in Wurzburg, hired Hartmut to purify and crystallize bacteriorhodopsin. When Oesterhelt moved to Martinsried to become Director of the Max Planck Institute for Biochemistry, Hartmut went with him, and this is how we met. 

The application of the selective application of interfacial films for energy band alignment in photoelectrochemical energy-converting systems is yet in its infancy, but the concept promises a very significant step toward the realization of stable and robust devices such as monolithically integrated water splitting structures. Such systems will be reviewed below. 

Oxygen (O2) is the most abundant element in the Earth s crast. The oxygen reduetion reaetion (ORR) is also the most important reaction in life processes such as biological respiration, and in energy converting systems such as fuel cells. ORR in aqueous solutions occurs mainly by two pathways the direct 4-electron reduction pathway from O2 to H2O, and the 2-electron reduction pafliway from O2 to hydrogen peroxide (H2O2). In non-aqueous aprotic solvents and/or in alkaline solutions, the 1-electron reduction pathway from O2 to superoxide (O2 ) can also occur. 

Secondly, with the correct combinations of different enzyme-layers, charged gels, layers, membranes or fibers and so on, energy-converting systems can be constructed and described mathematically. In other terms, structure-function-energy-comersion interrelations are predictable, computable and produceable. 

Fuel Cell Catalysts. Euel cells (qv) are electrochemical devices that convert the chemical energy of a fuel direcdy into electrical and thermal energy. The fuel cell, an environmentally clean method of power generation (qv), is more efficient than most other energy conversion systems. The main by-product is pure water. 

To calculate the amount of hydrogen produced by electrolysis powered from a wind energy conversion system within a year, the efficiency of the AC/DC (or DC-DC ) conversion 0/c) and the energy consumption of the electrolyzer (ecel) per newton cubic meter of H2 production need to be defined. The efficiency of a standard AC/DC converter ranges from 80% to 95% [41]. High values of t]c occur in the conversion of large amounts of power. Typical values of ecel range from 5 to 6 kWh/Nm3. 

Much has been written about artifical solar-energy converters - the reader is referred to references 10, 12, 14-17 for detailed treatments. Here I shall deal exclusively with those artificial systems designed to mimic various aspects of the photosynthesis reaction. 

Volvo is also a partner in another European project, the Capril project, which is managed by Volkswagon. A fuel cell VW Golf was built to run on methanol. Volvo developed the compressor, power converter and energy control system. 

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