Energy transition: World's largest battery is being built in Switzerland
Flexbase said the only financiers for the project, which costs several billion Swiss francs, are small and medium-sized companies or private investors from Germany, Switzerland and Austria. The investor did not provide any further details.
The planned location is a special one in the European electricity industry, because in 1958 the electricity grids of Germany, France and Switzerland were interconnected for the first time at the high-voltage level in Laufenburg. Even today, the small town is the electricity hub of Western Europe and is often referred to as the "heart of the European network".
In the electricity industry, people also speak of the "Star of Laufenburg" because 41 border lines converge there. This makes the location unique in Europe, says Marcel Aumer, Managing Director of Flexbase. The existing infrastructure enables a "direct connection of the battery storage system without detours and power losses".
The storage facility is to be used in various segments of the electricity market. On the one hand, it is to participate in electricity trading, i.e. to take in electricity when it is cheaply available on the stock exchange and to release it again when it is expensive . On the other hand, the storage facility is also to provide control energy to stabilize the power grid and it is also to serve as an emergency power source for the operation of an adjacent data center that is being planned and is to be used for artificial intelligence.
The storage will not be a conventional battery storage system, meaning it will not use lithium technology. Instead, a redox flow battery will be used. This is a system that stores energy in two liquids - two electrolytes. When the battery is charged, one liquid absorbs electrons from the other; when it is discharged, the charge carriers flow back again. If you want to increase the storage capacity of the battery, simply enlarging the two tanks is sufficient.
In order to achieve the desired capacity, Flexbase plans to build 960 tanks with 260 million liters of electrolyte fluid. The battery plant would take up a lot of space: the building would be 240 meters long and 80 meters wide, it would be 30 meters high and extend 25 meters underground. As things stand today, it would be the world's largest redox flow battery, as the Swiss company emphasizes. The largest of the plants is currently in China and has a capacity of 400 megawatt hours.
Flexbase emphasizes that this technology requires "fewer or no rare and problematic materials" and is very durable. In addition, it is less susceptible to overheating or fires than lithium-ion batteries. When asked, the company did not comment on the efficiency of the storage.
The most advanced version of the redox flow battery today is based on two vanadium salts in different oxidation states, each dissolved in 30 percent sulfuric acid. Another option is the zinc-bromine variant, but the systems are considered to be somewhat more sensitive.
Technical details for the Laufenburg model are currently still open. Flexbase says it will "set new standards in terms of the liquid used." It will not be decided until 2027 which technology will be used in detail. The battery is scheduled to go into operation in 2028.
taz
