In Volume 6 of the Advances in Solar Energy we have specifically targeted for a review the rich experience of the Power Utilities. Their hands-on experience in a large variety of means to employ solar energy conversion and to evaluate the technical and economical feasibilities is of great importance to their future use. In designing the lay-out for this volume, we wanted to collect all relevant information, including success and failures and wanted to emphasize the lessons learned from each type of experiment. The publication of such a review now has the advantage of a settled experience in the first phase of solar involvement of the utility industry with a large amount of data analyzed. We are confident that this information will be of great value to direct the future development of the solar energy mix within this industry. We have added to this set of reviews three articles which deal with the most promising high-technology part of solar energy conversion using exclusively solid state devices: solar cells. The development over the last two decades from barely 10% to now in excess of 30% conversion efficiency is breathtaking. In addition, the feasibility of economic midrange efficient thin-film technology holds the promise of opening large sc ale markets in the near future. This field will enter head-on competition for large power generation with more conventional technology.
