What is Wave Energy?
Waves are generated by the wind as it blows across the sea surface. Energy is transferred from the wind to the waves.
Wave energy is sometimes confused with tidal energy, which is quite different.
Waves travel vast distances across oceans at great speed. The longer and stronger the wind blows over the sea surface, the higher, longer, faster and more powerful the sea is. The energy within a wave is proportional to the square of the wave height, so a two-meter high wave has four times the power of a one-meter high wave.
Why Wave Energy?
Wave energy has the potential to be one of the most environmentally benign forms of electricity generation. It is a clean and renewable energy source and its potential is huge. Some additional benefits of wave energy are:
- With the wave energy resource distributed across the globe, wave energy offers many countries the benefit of security of supply
- Waves are generated over large areas of ocean and, once generated, travel immense distances with only small energy losses.
- Waves can be anticipated one or two days in advance through direct satellite measurements and meteorological forecasts which provide a high level of predictability and hence good network planning.
- Good seasonal load-following for regions where electricity demand peaks in winter given heating and lighting requirements (e.g. Northern Europe, Western Canada and North-West USA).
- Although wave energy is a concentrated source of wind energy, as it has often travelled very large distances it is regularly out of phase with the local wind conditions. Wave energy can therefore help to balance output variability from other renewable sources and maximise the efficient use of electricity networks
- Waves effectively average out the wind that generates them over large areas which results in a high level of consistency compared to wind or solar. Only on very few days per year are waves too weak to generate electricity.