Tidal energy is one of the great hopes of the renewable energy sector and Northern Ireland’s coast line is well suited to its exploitation. Leases are likely to be on offer later this year for new commercial tidal generators to be sited off the North Antrim coast.
A demonstration tidal energy project is already in operation in Strangford Lough, which is going well. That scheme is contracted to continue to 2012, but may be renewed beyond that. Another existing wave energy scheme is located at Scotland’s Isle of Islay, close to the Antrim coast.
All the UK’s offshore renewable energy schemes – those for offshore wind turbines, wave power and tidal projects – are leased by the Crown Estate, which (on behalf of the Queen, which means the taxpayer) owns the sea bed out for a distance of 12 nautical miles beyond the shore. There is a complication in the case of the border between Northern Ireland and the Republic of Ireland, as the nautical boundary was never agreed – but negotiations between the two governments are currently taking place to resolve this. What is agreed could affect future renewable energy schemes off the Foyle estuary.
The Crown Estate says that it hopes to begin arrangements later this year for the leasing of three sites off the Northern Ireland coast for new tidal energy schemes. It declines to say which sites will be chosen, explaining that this will be decided in consultation with the Department for Enterprise, Trade and Investment and the Northern Ireland Environmental Agency and based on the Strategic Environmental Assessment (SEA) published last year.
It is clear from the SEA which sites are most likely to be leased for tidal energy generation. But it reported: “The studies… identified significant tidal energy resource located within Strangford Narrows, around the Copeland Islands and Rathlin Island and off the north east coast between Fair Head and Runaby Head.”
The channel between Rathlin Island and Torr Head, near Ballycastle, was previously recognized in an assessment by the Carbon Trust as one of the ten best locations to harness tidal energy in the whole of the UK – potentially providing 4% of all UK tidal energy supplies. It could also meet 5% of Northern Ireland’s total electricity demand.
Thetis Energy has been formed to put forward a business proposal for a tidal energy scheme at Torr Head/Rathlin, which could generate 100-200 MW of capacity. Michael Harper, managing director of B9 Energy Offshore Developments, owners of Thetis Energy, says: “Northern Ireland has the clear potential to be at the forefront of tidal energy production. We have believed for some time that the currents created by the convergence of the North Atlantic with the Irish Sea provide opportunities for a commercially viable marine tidal stream project and we have been highly encouraged by the results of all the preliminary investigations and scoping exercises to date.”
Meanwhile, Minesto – a spin-off from the Saab car company – is also conducting experiments on the Antrim coast near Rathlin, using a different technology based on an underwater ‘kite’ to exploit tidal force. The company, which recently raised €2m in capital, believes its technology is superior and simpler than traditional tidal generators.
Tidal energy’s growing importance is demonstrated by the installation of what is thought to be the largest ever tidal turbine, which has been constructed by Atlantis Resources and is sited in a test location in the Orkneys in Scotland. It has the capacity to meet the electricity needs of about a thousand homes.
The significance of tidal energy in the Irish context is confirmed by Jim Kitchen, director of the Sustainable Energy Commission for Northern Ireland. “Around the whole island of Ireland, there is enormous potential – if we can crack the technology,” he says. “It’s a long haul. The whole environment is pretty dynamic and potentially quite violent. Queen’s [University] has a specialist group doing little other than tidal. If they can provide technology that works in all conditions it’s very exciting.”
Although tidal power has often been overlooked in the past as a major source of renewable energy, it looks as if, as they say, the tide has turned.