Rust-based battery connects to an electricity grid for the first time

An iron air battery that stores and releases energy thanks to a reversible rust process has become the first of its kind to connect with a public electricity grid. On July 30, the Dutch start-up Ore Energy announced that its batteries had connected to the Delft University of Technology University in the Netherlands.

Batteries can help provide a coherent supply of electricity by storing renewable energies from solar or wind parks, releasing it if necessary to ensure that a sudden change in sun or wind does not mean an immediate drop in available electricity.

“You must be able to store this excess energy when the wind blows and the sun is shining, to be able to deploy it when you need it during periods of critical demand during the day,” explains John-Joseph Marie at the Faraday Institution, a battery research organization in the United Kingdom. “Essentially, batteries can help smooth this output power to make it usable on the grid.”

Many batteries connected to the grid are now those of lithium iron phosphate made in China. But they generally have power for only 4 to 6 hours and are prohibitive, explains Marie. On the other hand, the iron batteries developed by the ore can store power for 100 hours or more and are made from inexpensive and widely available materials.

“Iron is the most extracted metal in the world, it’s incredibly cheap,” explains Marie. “And when you combine this with air, which is literally all around us and essentially free, it is almost the two cheapest components that you could find.”

The loading system and stores energy using electricity to convert iron oxides – a rust shape – in metal iron. The iron can then unload or release its stored energy by reacting chemically with the oxygen of the air to form the rust again.

“When the battery discharges, we take the iron and transform it into a special type of rust,” explains Aytac Yilmaz, CEO of Ore Energy. “And when we load the battery, we take the rust in iron, and we do it again and again [while] The battery breathes and exits oxygen at the atmospheric air. »»

The batteries are stored in standard 12 -meter shipping containers and can store several energy megawattheures – with 1 megawat -hour enough to provide more than a month of electricity to a typical American house.

In addition, the company based in Massachusetts Form Energy has several current air battery projects in the United States. They are planned for installation in New England and Midwest.

In addition to iron and air, these batteries incorporate water -based electrolytes which are also inexpensive and abundant – not to mention the risk of battery fire considerably. “I wouldn’t want to be the only one to say ever, but you can’t set fire to the water,” said Marie.

But the main objective of battery technology is to help renewable power sources to replace fossil fuels in electrical networks.

“Energy companies still count a lot on gas gas [power] Generation to provide the necessary flexibility when wind and solar energy are not sufficient, “explains Low kil, Director of Commercial Development at Ore Energy.” But in the long term, we will need a different type of flexibility, and this is where our battery really excels – to offer this flexibility of several days. “”