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New Zealand has large ocean energy resources but does not yet generate any power from them. TVNZ reported in 2007 that over 20 wave and tidal power projects are currently under development. However, not a lot of public information is available about these projects. The Aotearoa Wave and Tidal Energy Association was established in 2006 to "promote the uptake of marine energy in New Zealand". According to their 10 February 2008 newsletter, they have 59 members.〔(AWATEA February newsletter )〕 However, the association doesn't list its members.〔(Aotearoa Wave and Tidal Energy Association )〕 From 2008 to 2011, the government Energy Efficiency and Conservation Authority is allocating $2 million each year from a Marine Energy Deployment Fund, set up to encourage the utilisation of this resource.〔(Energy Efficiency and Conservation Authority ) - Marine Energy〕 The greater Cook Strait and Kaipara Harbour seem to offer the most promising sites for using underwater turbines. Two resource consents have been granted for pilot projects in Cook Strait itself and in the Tory Channel, and consent is being sought for a project sites at the entrance to the Kaipara. Other potential locations include the Manukau and Hokianga Harbours, and French Pass. The harbours produce currents up to 6 knots with tidal flows up to 100,000 cubic metres a second. These tidal volumes are 12 times greater than the flows in the largest New Zealand rivers. ==Tidal power== Tidal power is generated by capturing some of the energy in the tides as they cycle forth and back, twice each day. Tidal devices can be weir or dam like structures (barrages), used to hold the tide back, or turbines anchored within the tidal stream. By world standards, New Zealand's tides are, for the most part, moderate. The tide usually ranges between one and two metres. Tidal currents are usually around two kilometres per hour (one knot). Some exception are in and around Cook Strait, where tidal currents can be much stronger, and at the entrance to some harbours, particularly Kaipara Harbour.〔Stevens, Craig and Chiswell, Stephen. (''Ocean currents and tides: Tides'' ) Te Ara - the Encyclopedia of New Zealand, updated 21 September 2007〕 Headlands and constrictions like these focus the currents, giving energy levels reaching 750 W per square metre.〔Stevens, Craig; Smith, Murray and Gorman, Richard (2005) (''Ocean bounty: energy from waves and tides'' ) Water & Atmosphere, Vol.13, No.4.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ocean power in New Zealand」の詳細全文を読む スポンサード リンク
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