Close Log in with or
Register here
Forgot password

Register with or
* Required fields
your profile is 33% complete:
Update profile Close
Hydrogen bromide flow batteries.
Hydrogen bromide flow batteries.
Energy Energy Storage

Elestor uses the flow battery to extract the energy transition from the start.

They are fuel cell and electrolyser at the same time and store electricity much more effectively than other batteries. With its flow battery, startup Elestor hopes to smooth the faltering energy transition.

The company, founded in 2014, builds hydrogen bromide flow batteries. After a number of pilots on a small scale, Elestor now has four prototypes of the second generation. These are being tested this year in pilot projects. The intention is to take a standard module with a capacity of 50 kW into production next year. By linking them, large systems with capacities up to 2 MW can be assembled. Elestor's standard module is too big for some households, but according to director Guido Dalessi he can offer a solution for a block of ten houses. Soon a large system will be installed at a machine factory in Kampen (Netherlands) that has recently completed its roof with solar panels.

2 men in white cloth working on the flow battery in a labratory

The flow battery converts hydrogen bromide into, for example, hydrogen as soon as a voltage is applied across the central membrane. That is the charging process. At the moment when power is needed, the reverse reaction is activated, and the battery acts as a fuel cell. The active materials are not consumed, the system is completely closed. Only the diaphragm must be replaced after about 10,000 charge / discharge cycles. The efficiency of the storage for one cycle is 80%.

Second prize on Building Holland

The principle of the flow battery has been known since the 19th century. The Nasa did research in the 1960s and in the 1980s the first experiments took place that showed that it is possible to make more than 10,000 charge cycles with one battery. Since 2014, Elestor has been working from Arnhem on a hydrogen bromide flow battery in accordance with its own patented design. At the innovation award of the Building Holland trade fair, Elestor won the second prize this week.

According to general manager Guido Dalessi, the storage costs for the Elestor battery are much lower than for all other battery systems currently on the market: around 5 cents per kWh. For the well-known home battery from Tesla you have to count on 20 to 25 ct / kWh. The limit, which can be earned with a battery of money, is about 7 ct / kWh. The goal is to create an earnings model instead of a cost item, as has been the case up to now. Only then will the industry start to invest in the battery on a large scale.

Elestors gen pilot gen 2 pilot systemNegative electricity price on days with a lot of wind

In Germany, for example, the supply of wind energy is so high on some days that wind turbines have to be stopped. On such days, the power grid simply cannot handle the large power generated. The price for delivering power then quickly goes back and sometimes even becomes negative. In Germany, due to this so-called curtailment effect in 2015, companies already lost half a billion euros in income from non-generated wind power. Dalessi wants to bring that unused potential back to life with his battery. He talks about the missing link, which should smooth the faltering energy transition again. "With even more wind and solar energy, the energy transition only stops and, if we do not watch out, even ends up in the gravel pit. We get it out again."

By: Ad Tissink