The fundamental challenge of large torqueAt the quickfire seminar series at All Energy 2013, tidal energy veteran Peter Fraenkel (Fraenkel-Wright) gave his views on fundamental engineering challenges facing both tidal stream and wave energy: the lower the speed of the prime mover, the higher the torque, and the bigger the machinery. He estimated that tidal turbines were an order of magnitude slower, and WECs (wave energy converters) two orders of magnitude slower, than fossil fuel turbines.
Peter Fraenkel’s summation of the fundamental engineering constraints carried the implicit suggestion that wave energy would always be more expensive than tidal energy. Perhaps some insight might be gained from examining the reasons why tidal energy has progressed faster than wave energy. Of course I naturally feel compelled to defend wave energy as a matter of principle, so while I acknowledge that tribalism is a motivating factor for me, I shall do my best to prevent this from affecting my objectivity.