Directory of low carbon technologies

For more information about Low Carbon technologies select one from the list below:

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Marine

Marine energy comes from two main sources, waves (originating from solar energy) and tides (resulting from the gravitational pull of the moon and sun). Wave and tidal energy devices convert the oceans’ movement into electricity that is carried to shore using undersea cables and connected to the electricity grid.

The UK has some of the best tidal and wave resource in the world. Marine energy therefore offers high potential carbon savings and opportunities for economic development; the Carbon Trust estimates that between 15 and 20% of current UK electricity demand could be met by marine energy. Current costs are high, but would be reduced significantly through further device development and a reduction in component and installation costs. See our Marine Energy Accelerator and Marine Renewables Proving Fund for more information.

Wave energy

Wave energy occurs in the movements of water near the surface of the sea. Waves are formed by winds blowing over the surface and the water acts as a carrier for the energy. The amount of energy in each wave depends on its height and period (the time between successive peaks). The annual average power per unit in length of wave crest (e.g. 40 KW/m) is a good first indicator of how much energy is available at a particular site. Systems to convert wave energy into electricity can be located at deep water sites (offshore) or built into the coast line (near shore or shoreline). They vary in size from very large systems installed on their own, to smaller ones grouped into farms or arrays.

Tidal energy

Tidal energy can be grouped into two types, tidal stream and tidal range. Tidal stream energy results from large bodies of water moving around the ocean due to the gravitational pull of the sun and the moon. As water passes around peninsulas and through restrictions such as the channels between islands and the shore it accelerates, providing a potential source of energy The amount of energy it is possible to extract depends on the speed of the flowing tidal stream ( the ‘mean spring peak velocity’ is a good indicator of this). Systems to convert tidal stream energy take various forms, the most common extraction devices can be thought of as underwater wind turbines.

Tidal range systems use energy from the rise and fall of the tide in estuaries and bays. The larger the difference between high and low tide, the more attractive the site. Tidal range technologies are well developed, but there are currently no commercial scale examples in the UK.

For more detailed information on future cost-competitiveness and growth of wave and tidal stream energy click here.