Tides “could power half Scotland’s homes”

Published 22 Jan 2014

A study which predicts tidal energy from the Pentland Firth could power half the homes in Scotland, is "great news" for Caithness.

That's the view of Eann Sinclair, programme manager for the Caithness and North Sutherland Regeneration Partnership.

"A number of people have made estimates about the energy capacity of the Pentland Firth but I suspect this is the most realistic. We have a massive resource on our doorstep and the more people who confirm that the better," he said.

The study - carried out by engineers from Edinburgh and Oxford universities - says the firth could generate 1.9 gigawatts (GW) of power. While that is less than earlier estimates, it is still more than the 1GW forecast in research conducted six months ago.

Mr Sinclair said the academic standing of both universities was "second to none" and described their estimate as "a realistic assessment".

To exploit the energy potential of the tides in the stretch of water between Caithness and Orkney fully, the turbines would have to be sited across the width of the firth, states the study.

Mr Sinclair acknowledges the Pentland Firth is an important shipping, fishing and marine area and says a balance would need to be struck between the various interests.

"This research is great new for Caithness because respected academics are saying what people here have been saying for a long time," he said.

"I am not concerned that the estimate is lower than much earlier ones because what we have in the Pentland Firth is a huge resource and one that could power half the homes in Scotland.

"The focus has to be on how we can make best use of the Pentland Firth. I would hope this study reinforces what a lot of people already believe."

Mr Sinclair said the partnership was working with companies committed to making tidal energy a success.

The study was also welcomed by Caithness Chamber of Commerce. Chief executive Trudy Morris said: "This new research seeks to confirm what many have thought, that the Pentland Firth is a great untapped energy source.

"That said, the challenge remains for how this energy will be harnessed in what is an extremely harsh environment.

"It is vital developers get the support and investment needed to make it a reality."

She said MeyGen, which is involved in a tidal energy project in the Pentland Firth, is confident it can start to deliver the first tidal array in the next year. Ms Morris added: "We look forward to seeing this unfold over the coming years and we believe local companies can play a key role in assisting this development. MeyGen could lead the way to commercialising this tidal energy."

The study calculated the Pentland Firth, which has some of the fastest tidal currents in the UK, could produce as much as 4.2GW.

But as the turbines are not 100 per cent efficient the experts believe the estimate of 1.9GW is a realistic target.

They have outlined locations where turbines should be positioned to boost the area's energy producing potential.

Professor Alistair Borthwick from the school of engineering at Edinburgh University worked on the project.

He 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 Oxford University, who led the study, said: "These studies should move us closer towards the successful exploitation of the tides."

Last year MeyGen was granted consent to install a tidal turbine array in the Inner Sound. The project will be the first commercial deployment of tidal turbines in Scottish waters.

The phased project is expected to produce 86 megawatts (MW) of power which could generate enough electricity to power the equivalent of 42,000 homes.

A second phase would result in up to 400 submerged turbines in the firth, generating 398MW. Scottish Power Renewables is also involved in a tidal project at the Ness of Duncansby.