LAND, PUBLIC WORKS AND UTILITIES
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An extra high voltage transmission system at 400kV was completed in 1986 to transmit power from the Castle Peak Stations to the various load centres. Currently it comprises a double-circuit overhead line system encircling the New Territories, underground cables and eight extra high voltage sub-stations. Planning and construction work for the addition of new extra high voltage sub-stations and for the reinforcement of the existing system is in progress.
In HEC's supply areas, electricity is supplied entirely from the Lamma Power Station. At the end of 1994, the total installed capacity at the Lamma Power Station was 2 605MW. There are plans to add two 350MW units to Lamma one each in late 1995 and 1997.
HEC's transmission system operates at 275kV, 132kV and 66kV and distribution is effected mainly at 11kV and 380 volts. With the exception of a small proportion of 132kV overhead transmission lines, all supplies are transmitted and distributed by underground or submarine cables.
The transmission systems of CLP and HEC are interconnected by a cross-harbour link. This provides emergency backup and achieves cost savings to consumers through economic energy transfers between the two systems and a reduction in the amount of generating capacity that needs to be kept as spinning reserve against the tripping of other units. The interconnection, commissioned in 1981, currently has a capacity of 720MVA.
CLP's system is also interconnected with that of the Guangdong General Power Company of China and electricity is exported to Guangdong province. Such sales, which - Fare made from existing reserve generating capacity, are governed by an agreement with the government, signed in March 1992, under which CLP's consumers receive priority of supply and 80 per cent of the profit from the sales.
CLP also, in July 1985, signed a contract with the China Merchants Steam Navigation Company Limited for the supply of electricity, for a 10-year period starting from late 1986, to the industrial zone of Shekou and the adjacent Chi Wan area, both in Guangdong. The arrangement, which affords Shekou a reliable electricity supply without subsidy from Hong Kong consumers, is illustrative of the close co-operation on energy matters which has developed on both sides of the border.
CLP, through its affiliated company, the Hong Kong Pumped Storage Development Company Limited, has purchased the right to use 50 per cent of the capacity of the Guangzhou Pumped Storage Power Station, located at Conghua. The total installed capacity of the current phase is 1 200MW. The first two 300MW units were commissioned in early 1994, while the other two were commissioned in late 1994. Off-peak electricity from the Castle Peak Stations and Guangdong Nuclear Power Station is used to pump water from a lower reservoir to an upper one. The water is allowed to flow downhill during the day to generate electricity to meet Hong Kong's peak demand.
The Electricity Ordinance, enacted in 1990, provides, among other things, for the registration of electrical workers and contractors. The registration of electrical workers and contractors started in November 1990 and November 1991, respectively. To be eligible for registration, applicants must possess the necessary experience and qualifications. The Electricity Ordinance and its subsidiary regulations also require all electrical work to be undertaken or supervised only by registered contractors, and set out the standards for electrical wiring to which registered electrical contractors and workers have had to adhere from June 1992.