China’s State Grid Corporation is to invest some $88 billion in ultra-high voltage (UHV) power lines over the next 11 years to keep pace with electricity demand.

The country has already started operation of a pilot UHV power line and is in the process of constructing two major lines spanning 2000 km. State Grid also says that it wants to incorporate ‘smart grid’ technology into its power system to improve efficiency and flexibility.

Earlier estimates put China’s spending on UHV systems at 300 billion yuan ($44 billion) by 2012. UHV technology allows large quantities of power to be transmitted more efficiently than with conventional high voltage systems, and lines require smaller transmission corridors than the equivalent lines at lower voltages.

It is particularly suitable for countries like China, where large energy resources are located far away from demand centres.

Earlier this year State Grid Corporation said that European technology group ABB had successfully commissioned a switchgear unit capable of handling more than 1100 kV – a new benchmark in voltage levels. The development came just over a year after State Grid awarded ABB a $440 million contract to provide equipment for a 2000 km UHV power ‘superhighway’ linking power plants in western China to the industrialized east coast.

The incorporation of smart grid technologies into the transmission network in China will allow an increase in the share of clean energy, according to State Grid.

The UHV gas insulated switchgear designed by ABB and its technology partner Xian Shiky has a switching capacity of 6900 MW.