Capturing solar and wind: how Geyser Batteries can balance the grid

The grid needs a rapid way to balance input and output. Geyser Batteries of Finland may have the ideal solution.

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Grid management is a minute by minute, second by second, art form. Demand changes every time a kettle is turned on. Supply varies whenever the sun appears from behind a cloud or a gust of wind pushes a turbine's blades. The grid must balance demand and supply or hit a blackout or blowout.

What the grid needs is a way to store energy, and release, in the very short term. It's an issue Geyser Batteries is solving.  

Geyser is based in Finland, in a town called Mikkeli, a two and half hour drive north-east from Helsinki. The company specialises in aqueous electrolyte batteries designed for hundreds of thousands of fast charge and discharge cycles with minimal performance degradation.

“In the old world, power generation could react to disturbances in the grid,” explains Andrey Shigaev, CEO and co-founder of Geyser Batteries. “Coal, gas, and nuclear rely on turbines with big rotating mass that can offer smooth supply, and respond to changes in demand. Renewables can't do that. Solar and wind are highly intermittent and also can not really be controlled. A sudden flash of demand, or when the sun doesn't shine, and the grid struggles. That is a challenge.”

He points to unwanted frequency deviation away from the desired 50Hz. “Frequency deviation has been growing since 2017. The more renewables there are, the less reliable the grid.”

Here is where aqueous electrolyte batteries enter the equation. “Our electrochemistry team has invented a product that allows for hundreds of thousands of charges and discharges, at a fraction of cost of a supercapacitor.” The electrolyte is a solution of active salts, with water as the solvent. “That makes us a low carbon and low-cost technology.”

The battery can soak up excess power from volatile sources such as wind and solar, and rapidly stabilise the grid.

Ideal for short term fluctuations

The storage density is good, although not as high as lithium-ion. “The key is the power rate we can achieve,” says Shigaev. “Our product is the greenest and cheapest MegaWatt-minute. We have a compact device that can react really quickly to charge and release.”

The batteries do not heat up and are non-hazardous. The batteries can be discharged to zero with no impact on performance.

The batteries can be located strategically. One obvious place at the source of power generation, for example near a solar farm. But Geyser Batteries are also ideal close to consumption. “Imagine a bus depot, with electric buses stopping each round to top up,” says Shigaev. “The buses need extremely high power for a few minutes. It could be 300 kW to 1000 kW of power. Our batteries can pre-charge and then release in minutes thereby slashing power connection requirements.”

The advantage here is to reduce stress on the grid infrastructure. Setting up a 500kW supply, for example, requires a major upgrade of cables. With a Geyser Battery, the local site can keep its old infrastructure, using the battery to achieve high output for short time frames. 

The construction world is another potential customer. Anywhere using cranes, stackers, forklifts or generators may need a storage system on site. Geyser can work with grid supply or internal combustion engines to capture energy. Fire safety and size is a major selling point over lithium-ion alternatives.

The precise formulation of the electrolyte is confidential. There are a few varieties in use. Shigaev emphasises that all its battery ingredients are straightforward to source – there are no esoteric ingredients which might risk a bottleneck in supply.

Geyser is still in development mode. It is working on pilot programmes, two with utility companies and one with a charging infrastructure firm. It works with the likes of Shell, Ørsted and Fraunhofer Institutes to perfect the design and go-to-market. Geyser is now looking for EU funding to integrate its batteries into the grid.

Unlocking renewables

Are there rivals? “Always!” says Shigaev. “We are competing with supercapacitors, but our technology is simply better. There are approaches to bridge the gap with lithium-ion and supercapacitors. Unfortunately, the current designs just combine all the disadvantages of both technologies.”

Short term energy management is one of the lesser known challenges of adopting renewables. But solar and wind can't deliver stable energy without an intermediary storage system to cope with spikes in demand and supply.

Geyser Batteries is a young company, but it has the potential to solve this tricky problem. The path to net zero will be all but impossible without Geyser, or a rival, able to balance the grid.



A fascinating time for the energy storage sector

Callum McGuinn, Partner and Patent Attorney at Mewburn Ellis, comments:

"Large-scale storage will be an essential component of any transition to a grid powered by renewable electricity. Factor in their ability to compete with supercapacitors when it comes to high-power discharge, and Geyser’s batteries look set to become an important part of the large-scale storage landscape. The next few decades will be a fascinating time for the energy storage sector, and we’re excited to see the part Geyser come to play in helping the move towards net zero."



Written by Charles Orton-Jones