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The concentration of sunlight offers distinct advantages for solar–electrical generation either by thermal conversion or by photovoltaics. A large variety of concentration techniques are available with concentration ratios of 1–1000. Concentration is required for thermal conversion systems to attain the high temperatures needed for efficiencies in the desired range of about 25%–35%. The projected costs for some of the solar thermal systems (especially the central receiver and the fixed mirror) indicate that they could be economically competitive in the southwestern states. The southwest may be required for these high‐concentration systems to overcome the main disadvantage of concentration, which is the use of the direct component of sunlight only. Other concerns of high‐intensity systems are in tracking requirements, reflective surface accuracy, and material lifetimes of both the reflecting and absorbing components. Selective surface absorbers will be required for systems with concentration ratios below a few hundred. The present high cost of solar‐cell‐generated electricity can be reduced considerably by using concentrators. Cells can be used with any of the concentrator designs, and the major concern is keeping them at acceptable operating temperatures. Planar silicon cells, vertical multijunction, and gallium–aluminum–arsenide cells all look attractive for concentrating systems.