Wave Dragon is trying to get its seven-megawatt prototype into the water for a test run.
Harnessing the ocean’s restless energy has long been the dream of scientists, but making it a commercial reality has mostly eluded entrepreneurs. Iain Russell is the local manager of Wave Dragon, a floating, slack-moored wave energy converter composed of vertical turbines near the water’s surface. It’s stationed close enough to shore to transmit power to customers via underwater transmission lines. Wave Dragon is trying to get its seven-megawatt prototype into the water off Pembrokeshire for a test run. But as a small developer, it had to apply for a government grant and has been making its way through consultations, environmental impact assessments and approvals since 2005.
"There is no existing approval process for offshore wave energy installations," says Russell. "Several years and millions of pounds may be OK for a 300-MW offshore wind farm, but for a small wave developer whose device will only be in the water for a year or two, the process is not proportional." Several competitors around the world are working on and testing prototypes, and Wave Dragon has tested a prototype in Denmark. Another company permanently connected its device to the Italian grid from the Straits of Messina in 2006.
Wales" Severn Estuary has the second highest tidal range in the world. The lure of exploiting that energy has called out particularly loudly in recent years due to global warming, energy security concerns and rising fossil fuel costs. But the estuary is also protected by several national and international wildlife designations, so the debate is on.
The British government is currently considering two tidal technologies. One, essentially a dam called a barrage, uses the energy difference between high and low tides. The other, a tidal lagoon, consists of offshore catchment pools that would channel energy without blocking the entire river. Although the currently study is looking at different sized facilities, the largest would supply 4.4 percent of Britain’s electricity, or 0.6 percent of its total energy. It would also reduce less than one percent of its carbon emissions for an estimated cost of $29 billion and not come online until 2022.
"Harnessing the Severn will produce a long-term renewable energy source for Wales and also the UK," said Jane Davidson, Wales" minister for environment, sustainability and housing.
Most Green groups are vehemently opposed, both because of the destruction of rare habitat and because they say the project is a boondoggle that diverts time and money from energy efficiency, conservation and less environmentally damaging renewable energy technologies that would come online more quickly.
Britain is also considering in-stream tidal projects, which Matt Lumley of the Nova Scotia Department of Energy says are like underwater windmills that harness kinetic energy and have environmental and economic footprints much lighter than that of barrage technology. A tidal-stream "farm" is planned off the coast of north Wales, near Anglesey, and subject to approval could be completed by 2011. Its seven turbines could power 6,000 homes.
CONTACTS: Environment Wales, (011)029-2043-1727; Wales Environment Trust, (011)01633-811875
ERICA GIES is a freel
ance environmental writer.