Green Economy in a Blue World-Full Report

in a Blue World

Development in offshore wind capacity

Installed capacity in 2011 Planned installed capacity by 2020 Countries having or planning installations

Europe

Gigawatt 50

10 5 1

The capacity of 1 nuclear power plant is around 1 Gigawatt

Other European countries

0.5 or less

Source: Frauenhofer Institute for Wind Energy and Energy Systems, 2011.

• By building semi-permeable barrages across estuaries with a high tidal range. • By harnessing offshore tidal streams. The tidal barrage in La Rance, France is the world’s first tidal power station. The facility is located on the estuary of the Rance River, in Brittany, France. Opened in 1966, it is currently operated by Électricité de France (EDF), and is the largest tidal power station in the world, in terms of installed capacity, with a peak rating of 240 Megawatts, generated by its 24 turbines (Wyre Tidal Energy, 2012). Further, there is a 20 MW experimental facility at Annapolis Royal in Nova Scotia, a 0.4 MW tidal power plant near Murmansk in Russia, several locations in China since 1977, totaling 5 MW and the Sihwa Barrage in South Korea (254 MW) which is operational since August, 2011 (IPCC, 2011 and Ocean Energy Council, 2012). The UK has several proposals underway (Ocean Energy Council, 2012). Studies point to several other promising locations, including Alaska, British Columbia, Washington, Maine, the Severn River in England, and the White Sea of Russia (Ocean Energy Council, 2012). Tidal currents are the flow of water resulting from the rise and fall of the tides, particularly near islands or other natural constrictions. There is more potential for such resources to be harnessed, particular around headlands

showing rapid progress in offshore wind- energy installation. For instance, the UK added 90 MW in 2006 and another 100 MW in 2007 to its installed offshore wind-energy generation capacity (EWEA, 2009). 1.3 Tidal energy Tidal range is the change in height of water level driven by gravitational forces; the difference between high and low tides. While tides’ amplitude may vary during the year, depending on the relative positions of the Earth, Moon and Sun, they are regular and predictable. Tides are more predictable than wind energy and solar power and hence have the potential to generate stable income for the producer. Greater tidal ranges typically occur in estuaries and bays with the highest range being found in the Bay of Fundy, Canada (17m), the Severn Estuary, the UK (15m) and the Baie du Mont St Michel, France (13.5m). A tidal range of at least 7m is considered to be required for economical operation and for sufficient head of water for the turbines (Ocean Energy Concil, 2012) Tidal range power is a form of hydropower that converts the energy of tides into electricity. It works on the principle of turbine energy generation, where a tidal energy site consists of a storage pond, filled by the incoming tide through a sluice and emptied during the outgoing tide through a water wheel that drives turbines to generate electricity. Tidal energy can be exploited in two ways:

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