The major part of the world's first dual tower concentrated solar power (CSP) plant has started commissioning and testing in Guazhou County of northwest China's Gansu Province, and it is expected to officially generate power by the end of this year, said its operator, the China Three Gorges Corporation, on Monday.
The molten-salt CSP power plant, consisting of two solar towers, works by using nearly 30,000 mirrors that concentrate the sunlight onto the receiver at the top of the solar towers, which then heats the molten salt and drives electricity generators.
As the power plant can store surplus solar energy using the molten salt, it can deliver stable and uninterrupted electricity round the clock.
"The project adopts a dual-tower, dual-mirror-field design, so that the heliostat located between the two mirror fields can serve either solar tower, boosting the optical efficiency by about 24 percent under the same boundary conditions. The system also features a six-hour molten-salt thermal storage system, enabling long storage duration, rapid response, and stable power output," said Wen Jianghong, the project manager.
After being put into operation, the power plant is expected to generate 1.8 billion kWh of power annually, which can reduce carbon dioxide emissions by 1.53 million tons per year.
The project also incorporates various other innovative features to enhance the efficiency of power generation.
For starters, the project's mirror arrays can rotate freely and track the sun's position throughout the day like sunflowers, therefore converting a greater amount of solar energy into green electricity.
The mirrors feature ultra-white glass made from specialized materials, providing high optical clarity and the ability to reflect 94 percent of the sunlight towards the solar receivers.
The molten salt used in the solar power system has a boiling point of 600 degrees Celsius, able to store heat several times more effectively than water.
Compared with the conventional single-tower photovoltaic power plant, the dual-tower or even multi-tower design is not limited by installed capacity constraints. Therefore, its power generation efficiency, capacity, and energy storage capability will be significantly enhanced.
Known as CSP, solar thermal energy is believed to be the next generation of solar energy, and an ideal green power source.
World's first dual tower concentrated solar power plant starts commissioning, testing in China's Gansu
