Football scores a goal in mastery of wave power

Ben Marlow
AS he relaxed in the swimming pool of his bungalow in Dartmouth, Devon, Alvin Smith used a plastic football to help him float. He was struck by the powerful force the ball created when it was pushed below the surface.

“The water generated huge pressure. I immediately realised what an easy form of energy it is to create,” said Smith.

He believed it could be used to devise a wave-powered pump to bring water ashore and drive an electricity generator.

The thought lay dormant for 10 years. Then, in 2007, Smith constructed a prototype in his garden using four bath wastewater pipes, four snooker balls, a dustbin half-full of water, a steel rod and a plastic pipe.

He put it in the River Dart to see if it worked. “It immediately pumped water so I realised I was on to something,” he said.

Smith has since built a bigger pump and tested it off Dartmouth harbour. Left out at sea for a month, it pumped 112 cubic metres ashore each day — equivalent to a large swimming pool — through the simple motion of the passing waves. Once a hydroelectric turbine was fitted on land, the device generated a kilowatt of electricity a day.

Smith called it Searaser. It resembles a navigation buoy and the mechanics are simple. The pump is made of two 8 metre floats, one above the other, attached to a piston the size of a teacup. The passing waves lift the float, which raises the piston and pushes the water.

“It is the simplest device,” he said. Fixed to the seabed by chains and weights, it can operate in shallow water or far offshore.

Smith is excited about the implications for Britain’s energy needs. “We have just made a pump. The rest of the technology required to generate electricity already exists. It is cheaper than nuclear, completely emission-free and self-cleaning.”

The current model is a tenth of the size of what he eventually hopes to build. Smith is aiming for one that pumps 62,000 tonnes of water a day, which would produce nearly a megawatt of electricity — enough to power 1,700 homes.

That will require more money. Searaser has signed a joint venture with Ecotricity, a green power company, which has agreed to provide further funds.

Smith, 63, ran his father’s garage in Surrey for 30 years before moving to Dartmouth. “My plan was to retire to the West Country, but then I decided to explore this idea.”

The government failed to back him, so he was forced to turn to three local investors. The four men have put in £250,000 so far.

“I wrote to Gordon Brown, then met Ed Miliband [the energy and climate change secretary at the time], but I am still waiting.”

The interest from the coalition government has been more promising and Smith hopes Searaser will eventually be seen off coastlines round the world.

Working at half output, it would take approximately 34,000 Searasers to supply 20m British homes. “This country is surrounded by water, we need to put it to good use,” said Smith.