China’s first solar tower plant starts operating in desert

A water-tower-like chimney is eye catching in the desolate desert, where under the chimney is a glass-made house sitting above the ground.

This is a solar chimney plant system in Jinshawan, Wuhai City of north China’s Inner Mongolia Autonomous Region, which is the country’s first Concentrating Solar Power plant that combines solar and wind power into power generation.

Starting operation on Dec. 10, the 200-kilowatt concentrated solar energy can supply 400,000 kWh of electricity per year, saving the equivalent of 100 tonnes of coal and 900 tonnes of water, compared with thermal power generation.

China has been making efforts in emission control to fulfill its commitment of reducing carbon dioxide emissions per unit of gross domestic product (GDP) by 40 to 50 percent by 2020.

Based on the proposal for the country’s twelfth "Five-Year Program", which was released by the Communist Party of China Central Committee in late October, China should make the reduction of energy consumption intensity and carbon dioxide emission "binding goals" during the 2011-15 period.

Supported by the Ministry of Science and Technology and the Inner Mongolia Autonomous Regional Government, the project was co-designed and -developed by Inner Mongolia University of Science and Technology (IMUST) and the Technical University of Madrid, Spain.

"It took us three years to solve the technical bottlenecks," said Professor Wei Yili with the IMUST, who is a team member on the project.

The facility, composed of three parts — solar collectors, a chimney and a turbine generator — absorbs heat from the hot sand under the glass cover using the greenhouse effect, transmitting the hot air flows to the chimney and generating power by turning the turbine inside of it.

The energy stored in the sand, heated by the sunshine during the day,will discharge heat at night and continue to run the turbine, according to Wei.

"A feat of this facility is that an air door has been added to integrate wind power into the power supply, which enables the system to operate in winter when there is minimal sunshine. In this way, the system can operate 365 days of a year around the clock," he said.

Funded by a local company in Inner Mongolia with 1.38 billion yuan (208 million U.S. dollars), the project construction started in May 2009. It will consist of three phases covering a combined area of 277 hectares and its total generation capacity will reach 27.5 MW after the final phase is completed by 2013.

The power generated by the plant will then be transferred to the grid of Inner Mongolia and Hebei Province that provides electricity to Beijing, along with Hebei and Inner Mongolia.

Wei also noted that the most important substance in the technology was sand, which absorbs heat and accumulated energy. Therefore, the vast desert of west Inner Mongolia becomes the perfect site for locating such a plant.

More solar chimney plants of the kind will be built, taking the advantage of China’s 2.6-million-square-kilometer desert as "resources", Wei said.

"Energy saving, plus restraining sandstorms by covering the moving sand, the solar chimney plant is of great importance in improving climate," he noted.

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