RIASSUNTO
Abstract:
This paper outlines the potential for electricity production from the rapid tidal currents experienced in the waters around Orkney and Shetland, which lie off the north coast of the mainland of Scotland. The potential resource availability is examined, taking into account the limitations of technology and the acceptability of using the most promising waters for generation purposes.
1: Introduction
The most common perception of tidal power is of large barrage schemes such as that outlined for the Severn Estuary in England (Severn Tidal Power Group, 1986). The currents generated by the tides represent an alternative resource. The energy potential of the rapid tidal currents around the British Isles was the subject of a recent study (ETSU, 1992) and of other published material (Cave, 1986), (Cave, 1984), (Bryden, 1994). The ETSU study concluded that tidal current power could supply a major proportion of the UK''s electricity requirement but at a high cost (at least 10p/kWhr and probably much more). The ETSU study concentrated on major generation facilities producing strategic energy. This implied a requirement for major investment to enable long distance transmission of energy because of the remoteness of the major resource areas from the principal centres of population. In addition, as most of the sites considered were in the middle of major channels such as the Pent1snd Firth between Orkney and the Scottish mainland, there would be a requirement for offshore sub stations, requiring major civil constructions. Orkney and Shet1snd, however, possess IWTOW tidal cbsnnels which are subject to very rapid currents. These channels are relatively close to the main centres of population within the islands and, because the channels are IWTOW, the sub stations could be land based.
2. Resource Assessment
2.1 Power Available from Moving Water
Moving water carries kinetic energy.