China has developed an innovative method to store energy: a giant battery made of concrete blocks.
This battery was built in the city of Rudong, in the Jiangsu province of China, and takes the form of a ‘tower’ measuring nearly 148 meters high, i.e., about the height of a 50-floor building.
This construction aims to store energy by means of massive concrete blocks which will be lowered to produce electricity.
How does a gravity battery work?
The process is actually very simple to understand.
When wind turbines or solar panels produce more electricity than the network can absorb, this surplus is used to drive the blocks up.
Thus, the kinetic energy of these blocks will be transformed into electric energy and stored.
When the battery is charged, the blocks will be discharged at the bottom of the tower.
At this point, the kinetic energy of the blocks will be used again to produce electricity.
According to the article, this battery has a power of 25 MW and a storage capacity of 100 MWh, i.e., it would be able to provide its maximum power for 4 hours.
Why concrete blocks?
It must be noted that gravity batteries have a decisive advantage over lithium-ion batteries: they do not have any of the drawbacks of these latter batteries.
Indeed, this technology does not require any lithium, but concrete blocks, which can be reused or recycled.
In addition, they are much more resistant than lithium batteries.
The objective of this project is therefore to develop a technology that makes it possible to store electricity for a long time, using recyclable materials.
Support for renewable energies
As explained in the article, the development of this type of battery is part of an effort to facilitate the transition to 100% renewable energy.
One of the problems with renewable energy is that it is not produced at the same time as the need for energy.
However, a battery can solve this problem, by storing the electricity produced at times of low demand, to release it when the demand is higher.
This is why this type of battery could make renewable energy a reality.
While the sun shines or while the wind blows, gravity batteries could store this energy under the form of concrete blocks.
Then, in the evening, when the wind dies down or when the clouds cover the sun, this stored energy could be used to compress air and produce electricity.
Nevertheless, this technology has some disadvantages.
These batteries are not always competitive compared to lithium batteries, as they require a lot of infrastructure: concrete blocks, large areas of land, and large machines.
According to the analysis mentioned in the article, a gravity battery with a capacity of 100 MWh would be significantly more expensive and would occupy much more space than a lithium-ion battery.
According to the article, China is not the only country to have developed such a technology.
China is not the only country to have developed such a technology.
Indeed, there is also the Chinese project of an abandoned mine that stores energy.
Other projects are based on similar principles, such as using a slope to move concrete blocks.
These different projects show that this technology can adapt to different environments.
It is not necessary to build a tower of 50 floors: it is possible to imagine a version based on a slope.
The tower built in Rudong will be connected to the last grid , and it seems that this test will provide valuable information on the potential of this technology.
The real question is whether this alternative to lithium batteries can become a serious competitor.
More information:
knowledgeeducationguidessciencesnews