solar energy. They compare SPS and terrestrial photovoltaic energy conversion plants, in combination with storage systems to provide continuous powergeneration capability. The preliminary conclusions are that terrestrial photovoltaic power stations may be able to compete with SPS stations as baseload power plants, both in terms of investment cost and land requirement in locations with high insolations such as the Southwestern parts of the United States, but not in central Europe. They recommend further study of this issue. The European Space Agency started to assess the SPS concept in 1977. Following an initial compilation of the literature, the Agency's work has been oriented in three main directions: • collection and distribution of technical information on the SPS in order to stimulate a discussion on the potential role of an SPS in the future European energy scenario • identification of those aspects in the development and operation of an SPS that would be different in the United States and Europe • study of selected SPS technical problems in order to identify possible areas for European research and technological development. As a part of the dissemination of the technical information being gathered, a number of articles (9,10) have been published in ESA journals and a round-table discussion has been organized (12). The SPS was also discussed in a position paper prepared for the Agency's Member States and used as an input to the 1979 WARC, proposing consideration of the SPS by allocating an adequate frequency band to energy transmission (13). In 1979, J. Ruth and W. Westphal of the Technical University of Berlin performed a preliminary study (14) of the European aspects of solar power satellites under ESA contract. Some specific European factors were identified in this study. The Western European countries lie in the longitude range 24°W to 30°E, and in the latitude range 36°N to 72°N. This area is not only considerably more northerly than the United States, but it also includes a considerable number of East European countries, a fact that could give rise to serious political problems. Most of the major centres of electricity consumption, defined as circular areas of 100 km diameter and with consumptions of more than 3 GW, lie roughly between 45°N and 55°N (Figure 3). If SPS rectennas were to
RkJQdWJsaXNoZXIy MTU5NjU0Mg==