POTENTIAL FOR RECEPTION OF SPS MICROWAVE ENERGY AT OFFSHORE RECTENNAS IN WESTERN EUROPE P. Q. Collins Imperial College of Science and Technology, London, England There is an urgent need to establish the feasibility of receiving substantial quantities of energy from a Satellite Power System (SPS) in Western Europe (WE). Until this is done it is unlikely that the SPS will be considered as a serious candidate for future electricity supply by WE energy policy makers. The various problems associated with the SPS microwave power transmission and reception are already under investigation (see rest of this volume). When these studies are complete, the 'bottom line' for WE is to find sites for perhaps forty 5 GW rectennas, which could provide approximately 20% of WE el ectri ci tv demand in the year 2030. The selection of sites on land in WE would involve very substantial data handling, and is inherently unpromising due to the high population density. The selection of offshore sites does not face this problem, and was considered more likely to lead to a near-term positive result. For the present study a deliberately simple design, based on tried technology, was considered: The rectenna elements and structure are supported on light piles or floats, and completely surrounded by a protective sea wall. The cost of the sea wall depends on the depth of the water, and so site evaluation was restricted initially to areas with water depths of less that 25 metres, between 10 and 50 km offshore. Some twenty such areas of suitable size were identified around the Northern coast of WE, comprising some 20,000 square kilometres in total. The major factors relating to the offshore sites considered relevant to siting were: 1) Water depth 2) Distance from shore 3) Tidal range (including extremes) 4) Tidal currents 5) Wave heights and directions (including extremes) 6) Shipping lanes and traffic 7) Marine environment - fisheries, sea birds 8) Sea bed conditions - for support and/or tethering 9) Wind conditions 10) Other weather conditions - temperature, precipitation, lightning 11) Aircraft routes and telecommunications in surrounding area Additional factors relating to the land interface are: 12) Distance to major electricity demand centres 13) Distance to electricity grid interconnections 14) Availability of alternative generating capacity 15) Distance to docks, manufacturing facilities, etc. Data was readily available on most of these factors for the North Sea and Chan- . nel coasts, and on the basis of factors 1-10 above, some twelve areas were selected at which one or more rectennas could probably be sited -- many in water depths of 10 metres or less. The distribution of these areas was Belgium 1; Denmark 2; France 2; West Germany 2; Netherlands 2; U. K. 3. The Atlantic and Mediterranean coasts of WE have very few areas of water depth less than 25 metres. These areas, and the deeper water areas, will be considered in a later study.
RkJQdWJsaXNoZXIy MTU5NjU0Mg==