Solar thermal

Other includes net imports of coal coke and electricity produced from wood, waste, wind, photovoltaic, and solar thermal sources connected to electric utihty distribution systems. It does not include consumption of wood energy other than that consumed by electric utiUty industry. 

D. L. Klass, ed., A. Directory of U.S. Renewable Energy Technology Vendors, Biomass, Photovoltaics, Solar Thermal, Wind, Biomass Energy Research Association, Washington, D.C., 1990, for U.S. Agency for International Development, 74 pp. 

G. M. Reistad, paper presented at the Proceedings of the 2nd UN Symposium on the Development and Use of Geothermal Resources, Vol. 1, Lawrence Berkeley Laboratory, San Erancisco, 1975, pp. 2155—2164 "Analysis of the Economic Potential of Solar Thermal Energy to Provide Industrial Process Heat," U.S. ERDN Contract, EY-No-C-02-2829, Intertechnology Corp., 1977. 

Additionally, there are a number of useful electrochemical reactions for desulfurization processes (185). Solar—thermal effusional separation of hydrogen from H2S has been proposed (188). The use of microporous Vicor membranes has been proposed to effect the separation of H2 from H2S at 1000°C. These membrane systems function on the principle of upsetting equiUbrium, resulting in a twofold increase in yield over equiUbrium amounts. 

The extent to which each technology is poised to advance is described in separate discussions of photovoltaics, solar-thermal power, and wind, biomass, waste-to-energy, geothermal, hydropower, and wave energy. 

The first solar-electric technology to arouse industry interest was solar-thermal energy (1,3,5,6,8). Under favorable circumstances, it can be cost-effective, as evidenced by the fact that solar-thermal gas-hybrid plants produce over 350 MW of commercial power in southern California. This power is used during peak demand to supplement that available from conventional generation. 

The level of benefits from tax credits and favorable power purchase terms that helped give these installations their start has diminished in recent years. Nevertheless, with the remaining tax credits available and given current (ca 1995) natural gas prices, solar-thermal technology can deUver power at 8—12 /kW-h and an installed cost of 2500— 3000/kW. 

Solar-thermal technology uses tracking mirrors to concentrate sunlight onto a receiver. In turn, the receiver absorbs solar energy as heat, warming a fluid that then drives a turbine generator. Most solar-thermal plants requite cooling water. 

Fig. 3. The 10-MW Solar One plant, which advanced solar thermal power through the use of tracking mirrors to concentrate sunlight onto a central...

Three main types of concentrating collectors have evolved for use in solar thermal systems low concentration paraboHc troughs, high concentration parabohc dishes, and central receivers (Fig. 3). Higher concentration produces higher temperatures in a working fluid and makes electrical generation more efficient. 

Fig. 3. Solar thermal designs (a) parabohc trough (b) central receiver and (c) parabohc dish.

Unlike solar thermal systems or PV concentrator systems, the PV flat plate systems work well in cloudy locations because these latter convert diffuse as well as direct sunlight to electricity. On an aimualized basis, the energy produced by a photovoltaic array varies by only about 25% from an average value for the contiguous 48 states of the United States. As a result, it is practical to use photovoltaic systems in normally cloudy locations such as Seattle or northern Maine. 

Only about 10 elements, ie, Cr, Ni, Zn, Sn, In, Ag, Cd, Au, Pb, and Rh, are commercially deposited from aqueous solutions, though alloy deposition such as Cu—Zn (brass), Cu—Sn (bronze), Pb—Sn (solder), Au—Co, Sn—Ni, and Ni—Fe (permalloy) raise this number somewhat. In addition, 10—15 other elements are electrodeposited ia small-scale specialty appHcations. Typically, electrodeposited materials are crystalline, but amorphous metal alloys may also be deposited. One such amorphous alloy is Ni—Cr—P. In some cases, chemical compounds can be electrodeposited at the cathode. For example, black chrome and black molybdenum electrodeposits, both metal oxide particles ia a metallic matrix, are used for decorative purposes and as selective solar thermal absorbers (19). 

Solar Thermal from -High output -Complex design Not used. Considered... 

Garg, H. P. Mullick, S. C. and Bhargava, A. K. (1985). Solar Thermal Energy Storage. Boston D. Reidel Publishing Col. 

Direct use of the Sun s heat energy for supplying hot water for homes by special designs of rooftop units (Also known as Solar Thermal)... 

Atkins, M. J., Walmsley, M. R. W., and Morrison, A. S. (2010). Integration of solar thermal for improved energy efficiency in low-temperature-pinch industrial processes. Energy 35, 1867-1873. 

Schnitzer, H., Brunner, C., and Gwehenberger, G. (2007). Minimizing greenhouse gas emissions through the application of solar thermal energy in industrial processes. /. Cleaner Prod. 15,1271-1286. 

---