Energy storage and conversion

There are several approaches to the conversion of sunlight into electrical or chemical energy. The first method is the direct transformation into electricity by means of photovoltaic cells. These are based on a purely photophysical process, and they have been used successfully in many small-scale applications to provide electrical power for artificial satellites, for 

A photochemical process could use the energy of sunlight to split water into H2 and 02, the former then being used as a fuel which can be stored indefinitely. The splitting of water requires in principle a photoactivated catalyst dissolved or dispersed in water. The energy requirement for the overall reaction H20— H2 + 02 is 1.23 eV (per electron). In conditions of electrolysis it would however proceed extremely slowly at this potential difference which pertains to a thermodynamic equilibrium, and it is well known that a substantial overvoltage of the order of 0.5 V is required in practice to drive this reaction. 

In photochemical and photoelectrochemical systems the overall reaction, as shown above, is separated into two processes which are the oxidation of water to form 02 and its reduction to form H2. 

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School of Chemical and Biological Engineering Research Center for Energy Conversion and Storage, Seoul National University, Seoul 151-744, Korea... 

Hodes G, Manassen J, Cahen D (1976) Photoelectrochemical energy conversion and storage using polycrystaUine chalcogenide electrodes. Nature 261 403 04... 

Tributsch H (1985) Interfacial processes involving strong electronic interactions in solar energy conversion and storage. J Photochem 29 89-113... 

Chemical reaction has potential for both efficient energy conversion and storage. This part shows possibility of efficient thermal energy storage and thermal energy conversion methodologies by chemical reaction. 

Chemical heat pump is a representative of chemical thermal energy conversion and storage systems. This section shows fundamental of chemical heat pump. The knowledge would be applicable for other chemical energy conversion system. 

D. Sievert, D. Winkler, G. Scherer, A. Marek, and S. Stucki, in Electrode Materials and Processes for Energy Conversion and Storage, S. Srinivasan, S. Wagner and H. Wroblowa (eds.),The Electrochemical Society Proceedings Series. 

ENERGY CONVERSION AND STORAGE 9.16.6.1 Water Splitting by Visible Light using a Tandem cell... 

The International Journal of Sustainable Energy Conversion and Storage Robert Schlogl (Editor-in-Chief)... 

A.P. Pickett, in Proceedings of the Symposium on Electrode Materials and Processes for Energy Conversion and Storage, Edited by J.D.E. McIntyre, S. Srinivasan and F.G. Will, The Electrochemical Society, Inc. Pennington, NJ, p. 546, 1977. 

The accumulation of data on these metallic complexes in the area of solar energy conversion and storage [2], has allowed a rationalisation of the photochemistry of these compounds [3,4], Therefore they can now be easily applied in the context of DNA biochemistry. 

Photochemical Aspects of Solar Energy Conversion and Storage... 

It differs, thereby, from simple redox reactions such as Fe3+ + e Fe2+. Such reactions do not involve an intermediate radical and lack consecutive steps and alternative pathways. Study of their kinetics, therefore, omits characteristics of most electrochemical reactions met, e.g., in electrochemical synthesis, energy conversion and storage, or corrosion. 

Such ideas have initiated in vitro studies of chlorophyll-sensitized reactions in photosynthetic membranes from the laws of electrochemical kinetics. It has been possible to mimic the energy conversion and storage capacity of these membranes by experimental bilayer lipid membranes... 

A number of chromium(III) complexes with bipy, phen, terpy and related ligands have been prepared and their photochemical and photophysical properties investigated, mainly because of their potential applicability as photosensitizers for solar energy conversion and storage. Much of this work has recently been thoroughly and critically reviewed523 524 and a later article... 

J. O M. Bockris, B.E. Conway, E. Yeager and R.E. White, Electrochemical Energy Conversion and Storage, Comprehensive Treatise of Electrochemistry, Vol. 3, Plenum Press, New York, 1981. 

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