What are Marine Renewables?
Marine Renewables refers to the endless source of reliable, clean energy carried by the ocean's waves and tides. The movement of water in the world's oceans creates a vast store of kinetic energy, or energy in motion. Great news for us, as this energy can be harnessed to create electricity to power our homes, transport and industries.
Also known as marine energy, marine power, ocean energy, and ocean power, its worth noting that offshore wind energy is also sometimes included under the description of 'marine'.
How does Wave Energy work?
Waves are created by the interaction of the wind with the surface of the sea. As the wind blows over the water, it creates ripples. When the wind continues to push against these ripples, it creates a snowball effect resulting in a wave. The size of the wave depends on the speed and duration of the wind and the distance of water it blows over (the fetch). The wave carries kinetic energy transferred from the wind; the bigger the wave, the more energy it holds. This energy can then be harnessed by a mechanical device (often referred to as a Wave Energy Convertor) to produce electricity.
How does Tidal Energy work?
Tides are created by the interaction of the gravitational fields of the earth, moon and sun. These gravitational pulls cause the coastal water level to fluctuate twice daily, alternately filling and emptying natural basins along the shoreline. Tidal barrages or dams can be used to trap and release large amounts of tidal water. By releasing this trapped water through a turbine, electricity can be generated.
The ebb and flood of the tides also create tidal streams - fast moving currents, which are formed when water is forced through narrow channels such as inlets or straits. The energy carried by these currents can also be used to drive tidal current turbines to create electricity.