( CNN ) The United Kingdom may seem an unlikely candidate to lead a renewable energy revolution ; it does n't have much sun for solar power , it does n't have much space for wind power and it does n't have giant coursing rivers for hydro . It does , however , have thousands of miles of coastline and a lowering and restless sea whose tides ebb and flow with tremendous force . Energy companies in Scotland and Wales are seeing the potential from underwater turbines which tap a constant and predictable source of energy , are invisible and can produce as much electricity as a conventional wind turbine . If a test project in the fast flowing marine waters of Pentland Firth in the far north of Scotland goes well , submerged turbines could eventually power as many as 400,000 Scottish homes , according to the Scottish-government backed scheme . Predictable flow . `` The demonstration array at the moment is 6MW or four turbines . Hopefully this will be the catalyst for further investment , '' MeyGen CEO Dan Pearson told CNN . `` We are looking to complete construction of that in 2016 . '' Sea water is 832 times denser than air , which means the turbines can be smaller while producing a similar amount of energy to a wind turbine . The force of these tides also means the turbines can be placed closer together , taking up less space on the sea bed than an equivalent wind farm on land . Apart from being invisible -- obviating a factor that has stalled many wind farm projects on land -- the marine turbines have the great advantage of tapping an energy source that does not rely on the weather . Other renewables such as wind , wave , solar and even hydroelectricity depend in large part on seasonal and climatic features , tidal turbines , meanwhile , get two regular tide changes a day . `` We can forecast over the next 100 years pretty accurately -- we know when the power 's coming , '' he said . Scrap metal as an anchor . The plan is for the stands for the turbines to be lined up 525 feet ( 160m ) apart and weighted to the sea bed with scrap metal . With a depth of 130ft ( 40m ) , Pearson says that vessels would have a clearance of about 8m , plenty , he says , for the small craft that ply the four mile region . `` These are really cut down versions of wind turbines , such that most of the electrical equipment is onshore so that if something goes wrong , we can get a Land Rover and drive to the substation rather than having to get a boat and pick them up . `` That 's one of the core advantages of this technology . '' Other issues such as maintenance and corrosion have been solved , in large part , by using the advances in other technologies . `` It makes use of a large knowledge base , for example the seals and solutions have been solved by propeller technologies on ships , problems of corrosion are well known from subsea structures like bridges or oil rigs . `` What you 're seeing is nothing brand new , it 's just a lot of components coming together and I think that 's the beauty of it . '' Safe for sea life ? Concerns over the impact on marine life were also raised during the planning process , but Pearson said the simple fact is the turbines move so slowly -- at between 12-18 RPM -- that experts believe most sea life would be able to either ignore or get out of the way of the blades with ease . `` We 've been working closely with institutions such as Scottish Natural Heritage and the Royal Society for the Protection of Birds because we have diving birds in the area , '' Pearson said . `` We have seals , we have whales , we have dolphins -- it 's beautiful up there . '' He said undersea monitors have been logging the wildlife in the region over the past five years and that various groups now have a clear baseline of which animals populate it . `` There has been a lot of work done in other parts of the world on how seals and whales interact with these turbines and they do actually get a bit curious . `` But these rotations of the blades are quite slow in comparison with wind turbines and the theory is that they can just get out of the way . He said research had shown that most marine life avoids tidal surges when they are in full flow . `` I can imagine seals dancing around them , but the only time they 'll be playing around them is when the flow is benign -- and that only lasts for about an hour and a half and at that time the blades are n't rotating . `` We do n't want to be blasé about it , but at the same time we have a high degree of confidence . '' The immediate future of the energy source , he said , was looking good , with leases around Scotland showing the potential to produce 1.2GW -- more than twice the energy produced by an average-sized nuclear power plant . `` The UK has a good chance to develop and manufacture these turbines for world consumption in a beautiful part of the world which currently has a low GDP , '' he said . Read more from Tomorrow Transformed : . The first ever 3D-printer President . The hottest apps in tech right now . What can you buy off the Darknet ?
Energy companies in the UK see potential from underwater turbines that produce electricity . The energy is consistent and predictable ; companies can model output 100 years in the future . Meygen has placed four turbines in the north of Scotland to tap the tidal power of Pentland Firth . Comment: