Green energy company Ecotricity is broadening its existing wind and solar renewable energy stable with the addition of an innovative marine energy capability costing less than 2p per kilowatt hour if the technology lives up to its potential.

The Gloucestershire-based business has today announced that it is developing a radical wave power device called Searaser – which it believes can address two of the biggest barriers to the deployment of renewable energy on the scale that Britain needs – cost and variable output.

Searaser is the brainchild of Devon engineer Alvin Smith and it harnesses the power of ocean swells to create electricity.

The announcement coincides with moves by the Department of Energy and Climate Change to make the South West of England the silicon valley of Marine Energy technology.

Ecotricity founder Dale Vince said:

“Our vision is for Britain’s electricity needs to be met entirely from the big three renewable energy sources – the wind, the sun and the sea.

“Until now, the sea has been the least viable of those three energy sources and we believe that Searaser will change all of that. Indeed we believe Searaser has the potential to produce electricity at a lower cost than any other type energy, not just other forms of renewable energy but all ‘conventional’ forms of energy too.”

Inventor Alvin Smith said the main barrier to making wave-power efficient and therefore cost-effective – was resilience against the hostile ocean environment.

“Most existing wave technologies seek to generate electricity in the sea itself. But as we know water and electricity don’t mix – and seawater is particularly corrosive – so most other devices are very expensive to manufacture and maintain.

“But Searaser doesn’t generate the electricity out at sea. It simply uses the motion of the ocean swell to pump seawater through an onshore generator.”

New technology will supply energy on demand

 Searaser pumps seawater using a vertical piston between two buoys – one on the surface of the water, the other suspended underwater and tethered to a weight on the seabed. As the ocean swell moves the buoys up-and-down the piston works like a bicycle pump to send volumes of pressurised seawater through a pipe to an onshore turbine to produce electricity.

This opens up the additional option for Searaser units to be used to supply energy on-demand. By pumping seawater into a coastal storage reservoir, it can be released through a generator as required – thus making not just energy from the Sea but energy that can be turned on and off as required.

The proposed system would go a long way to solving the problem of renewable energy’s naturally intermittent output on Britain’s electricity grid.

Ecotricity’s move into wave power comes as the Government and the Crown Estate make changes that they hope will encourage more development of wave-power in Britain.

At the start of 2012 the Crown Estate – which owns the seabed surrounding the UK –reduced the burden of financial guarantees it requires from wave and tidal developers to obtain a lease option from £25 million to £5 million.

First commercial Searaser on stream in 12 months and 200 in five years

Dale Vince said Ecotricity’s investment will drive the next phase of SeaRasers' development, by having a commercial scale Searaser in the Sea within 12 months and 200 Searasers around the British coastline within five years.

Vince said:

“The potential is enormous.  This is a British invention that could transform the energy market not just here in Britain but around the world.  Our plan is to develop the technology and make them here in Britain, bringing green jobs as well as green energy to our country.”

According to Ecotricity, if the Searaser technology lives up to its potential it will reduce energy costs by an order of magnitude. At an estimated cost of less than 2p per kilowatt hour, this would make Searaser energy four times cheaper than even the lowest-priced renewable energy source currently on the marketplace/