LUREG

Sea waves carry large amounts of energy. If only part of this energy were to be captured, it could provide a good proportion of the energy needs of countries like the UK, where there is a lively wave climate off the coast. This possibility has interested engineers for decades, and has generated a large variety of designs for wave-energy conversion devices - but so far without any one design taking the lead. The question of how best to capture the energy in sea waves is a complex and challenging one. The pages within describe first the complex nature of waves and how they are generated by the wind, and then the technologies designed to exploit the energy of this abundant renewable natural resource.

Tidal range devices exploit the potential energy stored in the raising and lowering of sea levels within an enclosed area during inter-tidal periods. The harnessing of the power within tides acts to restrict the flow, resulting in major changes to the environment within the tidal range. There are plusses, such as increased flood defence capacity, and negatives too such as loss of habitat. More information may be found in this section

Tidal Stream devices make use of the kinetic energy of moving water much in the same way as a wind turbine would in air. The major difference is that water is far denser than air.For a given power output, a water turbine will be much smaller than a wind turbine, but on the other hand greater engineering challenges face developers within this fledgling industry. Readers will find useful information regarding the basic priciples of generating electricty from tidal streams here.

In the UK, most large hydro power sites are already exploited, but there are many smaller sites where small-scale plant could be introduced. At many of these sites there are existing weirs where there is a low head of water (less than 3 m). It is only through installing small-scale plants at such low-head sites that the UK’s national hydro resource can be developed further. To make this possible, a low-cost system needs to be developed that is suitable for sites with only a small head of water.