In November, Li Junfeng, deputy director of the energy research institute under the National Development and Reform Commission (NDRC), the country's industrial watchdog and policy maker, said that the standard would be delayed until at least early 2011.
The national standard covers technologies for wind turbine control, power forecast and energy storage. It contains detailed requirements on technical specifications and performance of wind turbines, such as voltage, frequency, power factors, reactive power, low-voltage ride-through and monitoring communications.
It also sets out requirements for the management of grid integration, system adjustment and testing periods, dispatching and operation, power generation planning, safety and communication procedures.
The National Energy Bureau (NEB) has commissioned two bodies to establish the national standard. One comes from the electric power sector, mainly China Electric Power Research Institute under the State Grid. The other is from the wind turbine manufacturing sector. NEB will hear the views of the two organisations and combine their opinions.
Chai Jianyun, a professor from Qinghua University, says the national standard will basically follow the Technical Specifications on Integrating Wind Farms to the Grid, an industry standard enacted by the State Grid in December 2009. The national standard will be published as a guide, says Chai, and will set a relatively low threshold.
Even so, Chai says that if strictly implemented the national standard will increase costs for makers of wind turbines with a double-fed induction generator, which will have to be protected against damage in the event of a grid breakdown. These wind turbines represent about 80% of installed turbine capacity in the country.
Chai predicts that the standard will become stricter in the future, to match those for thermal power and hydropower.
Wind turbine makers largely say they can meet the standard. Liu Dongyuan, general manager of Guodian United Power, one of China's largest manufacturers, says: "Turbine manufacturers and wind farm operators believe the national standard is very appropriate, because we share the same ultimate target: to send wind power safely and steadily to the grid. This demands us to fully respect the requirements of the grid at the very beginning of producing wind turbines and constructing wind farms."
China will put forward a national testing and certification system, which the wind industry will have to meet in order to integrate to the grid. The National Wind Power Technology and Testing Research Centre will test turbines produced and installed in the country. Certificates will be issued by the China General Certification Centre and China Classification Society.
Industry insiders say this means China will evaluate wind turbines already in operation and gradually upgrade the unqualified turbines. It is expected to be easier and cheaper for Goldwind's permanent-magnet direct-drive turbines to be modified to meet the national standard than for Sinovel's turbines with double-fed induction generators.
The introduction of the standard, says Li, will add costs from installation of extra devices to solve problems such as active and reactive power, low-voltage ride-through, and harmonic wave control. The standards have nothing to do with giving preferential treatment to one type of turbine technology over the other, he says. Chai believes that modifications to a double-fed induction generator to meet the standard will cost CNY600,000-CNY700,000 ($90,000-$105,000).
More than 10,000 are in operation in China.
Liu says the standard will increase costs of research and development, and production. But, more importantly, the national standard will help promote industrial development and technological progress.
"The national standard will not be an obstacle for industrial development. The wind power industry and wind turbine manufacturing sector will develop faster under a high standard," he says.