(48 MW) will bounce off and almost all will miss the cavity receiver. Therefore, 148 MW (100 + 48) of the energy falling on the dishes will be removed from the system via electric power or reflected diffuse energy. The rest, 350 MW (344 + 6), will be rejected at the plant either at the collector, the Brayton engine, or the electric components. Thus, 70% of the total energy incident on the dishes will be rejected at the plant (350/498) as waste heat, and 30% will be removed from the plant site. The effective albedo of this plant is therefore 0.3 and is very nearly the same as that reported for avondale clay loam which is typical of the Southwest. The dry albedo was reported from 0.26 to 0.30, depending upon whether the soil was raked or not (Ref. 11). The net effect over the day is that no excess heat is rejected due to the plant. The remainder of the land area not covered by the collector may be affected by the presence of the plant. The ground surface itself may be changed, and the geometry of the incoming and ground reflected solar energy may be changed (blockage). These may contribute to the net heat balance. Although the magnitude of the heat may be the same, there may be a difference in the effects of the heat. The waste heat is rejected from the dish surface, cavity receiver, electric cabling, and the air heat rejection heat exchanger. This may interact with the environment differently than the solar energy absorbed in the ground. Also the energy removed by the plant is mainly in the form of electricity which acts as an energy "sink." The incident energy removed by the soil is in the form of reflected sunlight. Although this reflection leaves the plant area, it does interact with the atmosphere and clouds which may be in the vicinity. The presence of the collectors could affect the nighttime heat balance of the land. The collectors would block to some extent the radiation of heat from the ground to the sky. This might moderate nighttime temperatures, affect the amount of dew deposited on the ground at night, and impact the local vagetation
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