Electrical energy metering in China
The People’s Republic of China was established in 1949. Since then China’s electrical energy industry has experienced considerable progress. The annual growth rate of national total power generation and total installed power generation capacity is 12.5% and 10.8% respectively.
Six inter-province power grids have been formed, four of which exceed 30 million kW capacity. In 1996 China’s total installed generation capacity was 236 million kW, with annual power generation 1079.6G kWh. The national ninth five-year plan (1996-2000) makes provision for a further increase in power generation capacity of 80 million kW.
By the year 2010, the huge Tri-Gorge Hydro Power Station on the Yangtze River will be in operation. The national capacity will hit 500-600 million kW, and a giant power grid of 100 million kW, which traverses nine provinces from west to east China, will be formed. China’s energy bases are located in the west mountain region, where thermal power plants have been constructed near coal mines. A feasibility study to interconnect China’s national power grid with that of Russia is underway.
Since the late 1970s China has insisted on economic reforms and open politics, and the energy industry has grown rapidly. There are 757 509 villages in the country and 263 529 658 households in the countryside. The electrification rate was about 95% in 1996.
China’s electrical energy industry has been a government monopoly until very recently, managed by the Ministry of Electrical Power Industry of China. Since the regional economy develops unevenly all over the country, however, the energy industry has been in a state of imbalance. After years of effort to improve the infrastructure in the eastern well-developed coastal area, there is a buyer’s market as far as energy supply is concerned. In the under-developed western and central China, however, shortages in the energy market still exist. Because the power grids have not yet been networked, it has not been possible to adjust energy surpluses and shortages in any kind of organised manner.
Even though the energy industry is a government monopoly, China is following the world-wide utility deregulation trend. The Ministry of Electrical Power Industry was disbanded and reshaped as the National Electrical Power Company in 1998. In 1996 the National Power Grid Company was established to concentrate on power transmission. The power generation side has been de-monopolised and opened up over the past 20 years.
Electrical Energy Metering
Power generation has come a long way in the past 20 years, but the distribution infrastructure has become the bottleneck in the attempt to satisfy commercial and residential customers’ requirements. 1998 the Chinese government developed a three year plan to invest 300 billion RMB ($34 billion) to improve the power distribution network. Because metering makes up an important component of the electrical power distribution industry, considerable growth in this segment is also expected.
China’s watt-hour metering industry can be traced back about 100 years, when the first meter factory was set up in Shanghai. After the People’s Republic of China was established in 1949, a new meter factory was built in north-east China, with the help of the former Soviet Union. Today there are about 200 meter factories in China, the largest manufacturer being Holley Group Co Ltd, located in Hangzhou, the capital of Zhejiang Province. Its annual throughput of both Ferraris and electronic meters is about 10 million units.
Since China is moving in the direction of deregulation, the National Electrical Power Company (NEPC) must operate in terms of effectiveness and profitability. A one-household-one-meter (OHOM) policy is being implemented all over the country for electrical energy metering. The size of the domestic market is estimated in Table 1.
The technological trends in metering electricity consumption can be summarised as follows:
- For Ferraris meters, current mainstream products are Model DD28 and DD86 which adopt double-jewel bearings. Their designed lifetimes are 5 and 10 years respectively. In an effort to reduce costs, NEPC has called for Ferraris meters whose lifetime is 25-30 years. This meter should employ suspension magnetic bearing.
- The overload range for long life Ferraris meters (Imax/Ib) should be 4-6.67. This can meet projected natural growth requirements over the next 25-30 years.
- The NEPC has introduced automatic meter reading (AMR) technology in order to reduce the cost of meter reading and billing. Reliable power line communication (PLC) technology is very promising.
- The communication requirements of AMR have resulted in the traditional Ferraris meter building in a pulse generator module. The full electronic meter market is booming.
- Prepayment metering is expected to be the technology of choice to implement OHOM.
- Big customers whose transformer capacity is larger than 50 kVA already use time-of-use metering. TOU metering will be put into practice for residential customers in the next 3-5 years.
|Year||Total Quantity||Single Phase||Poly-phase|
|Single phase||Poly-phase||Ferraris||Full Electronic||Ferraris||Electronic|