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New Zealand's electricity market (NZEM) is regulated by the Electricity Industry Participation Code administered by the Electricity Authority (EA). The Authority was established in November 2010 to replace the Electricity Commission. == Overview == Until 1987, New Zealand had a centrally run system of providers of generation, transmission, distribution, and retailing. Since then, a step-by-step process of industry reform has led to the separation of the monopoly elements from the contestable elements to create competitive markets in energy generation and electricity retailing, while imposing regulation on the natural monopolies of transmission and distribution. Currently the market is split into the following areas: regulation, generation, administration and market clearing, transmission, distribution, metering and retailing. The wholesale market for electricity operates under the Electricity Industry Participation Code (EIPC),〔(【引用サイトリンク】 title=The Code )〕 and is overseen by the market regulator, the Electricity Authority. Trade takes place at more than 200 pricing nodes across New Zealand.〔(【引用サイトリンク】url=http://www.systemoperator.co.nz/f1684,1999807/1999807_connecting-dispatching-new-generation-nz.pdf )〕 Generators can make offers to supply electricity at grid injection points, while retailers and some major industrial users make bids to withdraw "offtake" electricity at grid exit points. The market uses a locational marginal pricing auction which takes generators' offers and retailers' bids, and computes final prices and quantities at each node. The auction is held every half hour. The Electricity Authority contracts out the services required to run the electricity market. The Reconciliation Manager who reconciles all metered quantities, the Pricing Manager who determines the final prices at each node and Clearing and Settlement Manager who pays generators for their generation at the market clearing price and invoices all retailers for their offtake, are all contracted to New Zealand Exchange (NZX), who acquired the previous service provider M-Co in June 2009. The owner of the national transmission grid is Transpower, a state-owned enterprise. Transpower is also the System Operator, responsible for ensuring real time electricity supply security and quality. Transpower is the market scheduler, predicting likely demand to help generators make offers, and the dispatcher, in charge of matching demand and supply in real time. Distribution of electricity from the grid exit points to the end consumers' premises is the responsibility of about 30 distributors, also known as lines companies, who have monopoly control of the lines services on their networks. Ownership of distributors is through trust-owned companies and public companies. Some major industrial users are directly connected to the grid, such as New Zealand Steel and the Tiwai Point Aluminium Smelter. There are five major generators: Meridian Energy, Genesis Energy, Mighty River Power, Contact Energy, and TrustPower. These five together produce about 95% of New Zealand's electricity. Meridian Energy, Genesis Energy and Mighty River power are 51% majority owned by the New Zealand government, Contact and TrustPower are 100% publicly traded companies. An important feature of the New Zealand market is that all the major generators also own retailing arms. The companies are thus commonly known as "gentailers" (generator–retailers.) Retailers purchase electricity from the wholesale market, and on-sell it to consumers. Competition for retail customers varies across the country but since 1999, when full retail competition was introduced, customers have switched at a rate between 9% and 14% per annum.〔(【引用サイトリンク】author=New Zealand Electricity Commission )〕 Consumer NZ, with support from the Ministry of Consumer Affairs, provides a website called (Powerswitch ) that enables consumers to compare electricity prices from different retailers and to switch suppliers. 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「New Zealand electricity market」の詳細全文を読む スポンサード リンク
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