Saturday, June 22, 2024

World’s largest compressed air energy storage plant connected to grid

Global electricity demand is constantly growing, making the utilization of solar and wind energy sources, which also reduce negative environmental effects, more and more important. However, the intermittent nature of these clean energy sources remains a challenge to grid operators when scheduling power generation. Therefore, the need for energy storage in electricity networks is becoming increasingly important.

Some of that comes in the form of big battery installations. But due to shortages of critical materials and vulnerable supply chains, production of lithium-ion batteries could fall far short of demand.

So, China has diversified its efforts. Just last week, it switched on the world’s largest flow battery energy storage station, connected to the grid in Dalian, China. The station offers relatively low-cost energy storage without using any lithium.

Now, after several years of development, the Chinese Academy of Sciences announced that it has successfully connected the world’s first 100-MW advanced compressed air energy storage (CAES) system to the power generation grid. The national demonstration project is also the largest and most efficient advanced CAES power plant so far. The system is ready for commercial operation in Zhangjiakou, a city in north China’s Hebei Province.

The CAES power plant can generate more than 132 million kWh of electricity annually, providing electricity for 40,000-60,000 households during peak electricity consumption. It will save around 42,000 tons of standard coal and reduce carbon dioxide emissions by 109,000 tons annually.

Conventional CAES utilizes renewable electricity in valleys of electricity demand to compress and store air in large storage caverns. At peak electricity demand, high-pressure air is released from the storage caverns and combusted with fuel to drive turbines for power generation.

CAES has the advantages of large storage capacity, low capital cost, long lifetime, safety, and environmental friendliness. It is recognized as one of the most promising technologies for large-scale energy storage. However, the application and promotion of the technology are restricted by its dependence on fossil fuels, large storage caverns, and low system efficiency.

The Zhangjiakou 100-MW advanced CAES project was launched in 2018. The system utilizes an artificial air storage vessel to improve energy storage density and reduce dependence on a large gas storage cavern. Recycling compression heat solves the dependence on fossil fuels.