Hammersfest is trialling their first undersea turbines off Orkney and the BBC went to look. Before I lead you to the story, a few facts. These monsters have a base weighing a thousand tons, are manufactured in Norway, bases I believe in Bristol, they produce just one megawatt and only operate for short six hour spells. They cost a king’s ransom and you would need one thousand of them to replace a coalfired power station. As you will see from the BBC reports they are the most expensive form of energy there is. Tides are realiable within certain parameters. They are only available for relatively short, although predicyable periods. The BBC report is actually very good. Click to read.