Britain is already the world leader in wave and tidal energy but greater collaboration between utilities and developers deploying marine power devices is needed if that position is to be maintained, the Carbon Trust has warned.
The UK has the potential to capture around a quarter of the global marine energy market and to reduce the cost of wave and tidal power to around that of offshore wind and nuclear, according to an analysis by the trust. But utilities and wave-energy device developers should consider working together to solve common problems, said the trust.
This would help to reduce the cost of marine energy to levels comparable with offshore wind and nuclear from current levels of 30-40p/kWh. The trust said it was feasible that costs could come down to the same level as offshore wind within the next 15 years.
Charlie Blair, the trust's technology acceleration manager for marine renewables, said: “It will be difficult. We know from working on the technology that there are big challenges, and the primary one is getting the cost down. But it is feasible. We now know that these technologies work.”
The Carbon Trust analysis shows that wave energy could generate 50TWh of electricity per year, equivalent to 13% of the UK’s power needs, and tidal stream 20.6TWh per year, or 5% of UK power needs. Between them wave and tidal stream could generate more electricity than 12 large coal-fired power stations, claimed the trust.
The fast-flowing tides of the deeper areas of the Pentland Firth between the Scottish mainland and the Orkneysalone could generate almost one third of all tidal-stream energy (6TWh/year), and at an equivalent cost to nuclear and onshore wind.
Separate Carbon Trust analysis has shown that the UK could capture just under a quarter of the global marine energy market. Contributing up to £76 billion to the UK economy by 2050, this growing sector could also generate more than 68,000 jobs.
Blair said that Britain was already a world leader in marine energy. British companies such as Pelamis, Aquamarine Power and Marine Current Turbines are leading the way in deploying their technologies in UK waters, with six out of the eight full-scale prototypes in the world being installed there.
Almost half of Europe’s wave resources and more than a quarter of its tidal-energy resources are to be found off the British coastline. Britain has the advantage of having bountiful wave and tidal resources in proximity to heavy demand for electricity compared with many other parts of the world.
Blair said the trust would now like to see greater collaboration among utilities on non-competitive aspects of wave and tidal device development and deployment. “We've been funding R&D work toward cost reduction through the marine energy accelerator over the last five years, but there's a certain danger that we're funding the individual developers to do their bit of work on maintenance, operations or installation procedures. We'd like to see the industry starting to work together on the bits that are not competitive,” he said.
“There's certainly scope for collaboration on tidal installation, for example. We've learnt that installing tidal devices is really difficult and expensive, and it's not yet been determined what the best solution is.”
Meanwhile...
A small British renewable energy company has won the financial backing of German marine propulsion giant Schottel that will enable it to build a £12 million demonstrator of an innovative multi-turbine tidal generator.
TidalStream said the backing would secure its future for at least the next three years, during which time it would construct a 3MW test system, likely to be installed at the European Marine Energy Centre (EMEC) in the Orkneys.
The Triton 3 is a three-rotor turbine device designed for mid-depth waters of between 35 and 50 metres. The company said the design enabled highly cost-effective deployment and adaptable operation, allowing a number of alternative turbines by different developers to be used. It features a semi-submerged turbine-carrying catamaran structure secured to a seabed anchorage by a rigid swing-arm tether. The platform can be towed to site already assembled, then deployed into its operating position by waterballasting. De-ballasting will bring the system to the surface when required, allowing on-board access for scheduled maintenance and unplanned repairs.
Mike Todman, co-director of TidalStream, said: “We are not revealing the exact amount of the Schottel investment but it will allow us to build and test a full-scale demonstrator within the next two to three years.
“EMEC is interested in trialling our system, because it can also act as a test bed for other developers' turbines.”
A 10th-scale version of Triton 3 was tested last year in a tidal area of the Thames in London. Onboard control equipment enabled remote ballast changes for the transition between the floating maintenance mode and submerged operational mode.
“River testing was a step forward from tow-tank testing, as it introduced turbulence and beamwave effects (from passing wakes) that were difficult to create in a test facility, but would be experienced in full size installations at sea. This testing will continue throughout 2011,” said Todman.