Wave-energy conversion research in Norway with emphasis on phase control

The 1973 energy crisis resulted in certain individual initiatives to study energy conversion of ocean waves. A substantial R&D programme was funded by the Norwegian government from 1978 and some years onwards. During the early 1980s, three different types of 200-MW wave-power plants were assessed, technically and economically. For two of the three types, single-unit prototypes (~0.5 MW) were sea-tested on the western coast from 1985 and some years onwards. For the third type, which utilises the principle of latching for phase (and also amplitude) control, it was considered that further technical development of certain components was necessary before sea-testing a full-scale unit. The principle of latching control was explained in the lecture. Its potential advantages, and some of its technical challenges, were illustrated by considering an example of a heaving semi-submerged sphere.