Video | my country’s first 100-megawatt giant “power bank” was successfully connected to the grid

Today (October 2), my country’s first hundred-megawatt compressed carbon dioxide energy storage project, China Huadian Xinjiang Mulei Compressed Carbon Dioxide Energy Storage Project, was successfully connected to the grid, opening up a new green, zero-carbon, efficient and economical route for large-capacity compressed carbon dioxide energy storage.

The first 100-megawatt class

Compressed carbon dioxide energy storage project connected to the grid

CCTV reporter Gu Junling:This is my country’s first 100-megawatt compressed carbon dioxide energy storage project. It is like a giant “power bank” standing on the Gobi Desert. It can flexibly store and discharge according to the needs of the power grid, charge at low valleys, discharge at peak times, and respond in minutes. It can store 290 million kilowatt hours of electricity every year when the power grid is at low times, and release 180 million kilowatt hours of clean green electricity at peak times. It can continuously generate electricity for more than 6 hours.

The project is equipped with 5 gas storage silos, 141 liquid storage units and 97 thermal storage units. The entire system uses carbon dioxide as a closed circulation medium. It is an energy storage technology in which gas and liquid interchange and the two states cooperate. It does not rely on geological conditions, has low pressure and temperature requirements, high reliability and low cost. The key core technologies of design and manufacturing are completely independently controllable.

Ma Guojiang, person in charge of China Huadian Mulei Compressed Carbon Dioxide Energy Storage Project:Compressed carbon dioxide has a higher energy density ratio and has many advantages such as high efficiency, low cost, high safety, and no pollution. The design efficiency of the project is currently the carbon dioxide power generation unit with the highest power generation efficiency in China. After the project is completed, the annual power generation will be about 200 million kilowatt-hours, saving 50,000 tons of standard coal and reducing carbon dioxide emissions by about 170,000 tons every year.

The project will strengthen the power grid’s peak-shaving and valley-filling, frequency and voltage regulation capabilities, significantly improve the flexibility and security of the power system, and continue to expand the supply of green power. It is of great significance to ensuring energy security and promoting green development, and will assist the economic construction of my country’s new power system.

How does compressed carbon dioxide energy storage generate electricity?

As a new energy storage technology, how does compressed carbon dioxide generate electricity?

The compressed carbon dioxide energy storage power generation system mainly consists of a gas storage system, a liquid storage system, a compression system, a heat storage system, a heat exchange system, and an expansion power generation system.

In the energy storage stage, during the low period of electricity consumption, abundant electricity is used to drive the motor to compress carbon dioxide at normal temperature and pressure through the compressor. This process is like using a pump to inflate a tire. The pump will generate heat, and a large amount of heat will also be generated when compressing carbon dioxide. The project will first store this heat, and then condense the compressed carbon dioxide into liquid for storage. This way, the energy density ratio is higher, which means that more energy can be stored.

During the power generation stage, during the peak period of electricity consumption, the project uses an evaporator to vaporize liquid carbon dioxide, and then uses the heat stored in the compressed carbon dioxide energy storage process to heat the high-pressure liquid carbon dioxide to a high-temperature and high-pressure gaseous state, and then drives the turbine blades to rotate, thereby generating electricity to generate clean green electricity.