A new estimate has said that tidal power generated by turbines placed in the Pentland Firth, between mainland Scotland and Orkney, could power about half of Scotland - they estimate 1.9 gigawatts could be available.

The Pentland Firth is a prime candidate to house marine power projects because of its tidal currents, which are among the fastest in the British Isles. To exploit the Firth's full potential, turbines would need to be located across the entire width of the channel. In order to minimize the impacts on sea life and shipping trade, a number of individual sites have been identified for development by the UK Crown Estate, which will lease these sites to tidal energy firms.  

Researchers have pinpointed locations where turbines would need to be positioned for the Firth to meet its full energy production potential.

The engineers  from the Universities of Oxford and Edinburgh say that their study improves on previous estimates of the generating capacity of turbines embedded in the Firth – ranging from 1 to 18 GW – which were too simplistic or based on inappropriate models. Researchers calculated that as much as 4.2 GW could be captured, but because tidal turbines are not 100 per cent efficient, they say that 1.9 GW is a more realistic target.

Professor Alistair Borthwick, of the School of Engineering at the University of Edinburgh, said, "Our research builds on earlier studies by analysing the interactions between turbines and the tides more closely. This is a more accurate approach than was used in the early days of tidal stream power assessment, and should be useful in calculating how much power might realistically be recoverable from the Pentland Firth."

Professor Guy Houlsby of the Department of Engineering Science at the University of Oxford, said: "The UK enjoys potentially some of the best tidal resources worldwide, and if we exploit them wisely they could make an important contribution to our energy supply. These studies should move us closer towards the successful exploitation of the tides."