Green hydrogen electrolysers double up as batteries

How is this flexible system making clean hydrogen more accessible?

Spotted: Substantial efforts have been made by EU nations to move away from fossil fuels, but recent analysis suggests that the region is unlikely to reach net zero until the 2060s, a decade behind the 2050 target formalised in the European Green Deal. Emerging technologies, like hydrogen, could play a big role in closing that gap, and Battolyser Systems has a novel solution to make green energy more affordable and accessible.

As the name suggests, Battolyser has created what it claims is the world’s only system that acts as both an electrolyser and a battery. In 1901, Thomas Edison created the nickel-iron battery for use in early electric vehicles. Although the battery proved successful, one inconvenience was that it also generated unwanted hydrogen. A group of researchers at the Delft University of Technology saw this inconvenience as an opportunity and created the Battolyser using Edison’s same nickel-iron electrodes.

When clean, renewable energy is available (and cheap), the Battolyser is charged up. Once the battery is full, the system nonetheless keeps charging. When it does so, the full battery acts as an electrolyser, automatically splitting water to generate oxygen and green hydrogen, which can either be stored or used in applications such as industry and clean transport. Once renewable energy is no longer abundant and energy costs rise, the Battolyser stops producing hydrogen and can instead discharge its energy and sell it back to the grid for a profit. Or, for off-grid projects, the battery can be used to provide backup power.

This flexible system helps to overcome one of the key barriers associated with green hydrogen generation: cost. Not only are the raw materials used to create the battery abundant and low-cost, but the flexibility of the system also means users avoid generating hydrogen when energy costs are high and instead make money by selling the power back to the grid.

In October last year, Battolyser signed a €40 million financing agreement with the EU’s European Investment Bank, which is helping the company scale production and commercialise its flexible technologies.

Written By: Matilda Cox