In an effort to create enough electricity to power 175,000 homes, the Energy Technologies Institute of the United Kingdom (UK) has awarded a £7.5 million ($12.4 million) contract to a private firm to create a renewable energy “multi-turbine foundation structure” in a tidal stream in northern Scotland. Known as MeyGen, the project will be built by Atlantis Resources, Limited and will be the world’s largest tidal stream energy project.
The first renewable energy to be generated from the 398 megawatt facility is planned for 2016. Sixty-one water turbines (which resemble wind power turbines) will initially provide Scotland with enough power for 42,000 families. MeyGen’s three-bladed turbines will be installed below the ocean surface at Pentland Firth’s Inner Sound, near the northern tip of the country. When built out, the project could eventually see as many as 269 installed tidal turbines. The amount raised for the first phase of development and construction is £50.5 million ($83 million). MeyGen represents one piece in an ambitious puzzle Scotland has committed to solve for itself, to make the country completely independent of fossil fuels by 2020.
The turbines that will be installed at the MeyGen site work similarly to wind energy and, in fact, the machines look like those dotting above-ground hillsides around the world. In addition to perpetual / renewable energy, harvesting ocean movements has certain advantages; namely, that sea water is 832 times denser than air. This means that ocean currents carry a very high density of energy. Translated, a five-knot ocean current carries more kinetic energy than a 220 mile-per-hour wind and, in a boon to the economics of such projects, tidal turbines can be physically smaller than their above-ground cousins. The blades of tidal turbines move slower than above-ground turbines, which reportedly make them less likely to damage below-surface ecosystems.
In addition to tidal and wave power, another potential energy source is via the conversion of thermal energy latent in the world’s oceans. Overall, such possibilities represent enormous promise.
Funds for MeyGen started with an ante of £10.3 million ($17 million) from the UK’s Department of Energy and Climate Change. Other public funding was committed by Scottish Enterprise, Highlands and Islands Enterprise (both cheerleaders for Scotland’s business community) as well as The Crown Estate, one of UK’s largest property owners.
The first tidal renewable energy project was built by France in the 1960s. Since then, however, only a couple dozen more have been built due to the technicalities and high costs involved in fabricating an underwater power plant, as well as environmental concerns. Currently, the largest tidal energy project is a 254-megawatt facility in South Korea, which was switched on in 2011. UK Energy Secretary Ed Davey foresees the possibility of wave and tidal technologies providing more than 20 percent of that nation’s total electricity desires.
Technologies that harness ocean currents to generate electricity are promising but still in an initial state. Constant financing from public and private sources is required for such technologies to move into maturity. A parallel example could be solar power, which only now – after decades of slow-going – has become economically competitive with other forms of energy, such as coal. Commercial viability of tidal and wave technologies will occur after manufacturing has achieved certain economies of scale and engineering experience has been gained through successive installations.
By Gregory Baskin