The Danish startup Hyme Energy, which has developed a way to store renewable energy using molten salt, is teaming up with dairy producer Arla to create the world’s largest industrial thermal energy storage system.
The proposed system, with a capacity of 200MWh, will convert renewable electricity — from sources such as wind and solar — into heat, stored in molten salt tanks at over 500°C. This stored heat can be used on demand to replace fossil fuels in Arla’s milk powder production at its plant in Holstebro, Denmark, enabling up to a 100% reduction in CO2 emissions from process heat.
“This is the size of projects that we are looking to do, so it’s pretty exciting,” says Nis Benn, Hyme’s chief commercial officer. “It will show that reducing CO2 emissions in large-scale industries is not only feasible but also economically attractive.”
Hyme Energy spun out of Seaborg, a next-generation nuclear startup based in Copenhagen, in 2021. It accidentally discovered a molten salt storage solution using sodium hydroxide that could halve the cost of storing green energy, offering a viable alternative for industrial companies that rely heavily on fossil fuels.
The technology works by heating salt to 600ºC using resistance heaters powered by renewable electricity. The salt is pumped from a cold tank to a hot tank while being heated. The hot salt — charged with energy — is then stored there until needed. To release the energy, the salt is pumped through a steam generator, which heats water into steam for industrial processes or cogeneration. The cooled salt is then cycled back to the cold tank for reuse.
For industrial companies facing rising carbon emissions allowance costs in the EU, this solution could be transformative — not to mention its significant benefits for the climate. And with the EU’s agreement to the global phaseout of fossil fuels from the energy sector by 2050, it’s also a necessity.
The industrial challenge to decrease CO2 emissions
The industrial sector’s energy mix has remained largely unchanged since 2010, with fossil fuels decreasing only slightly from 74% of the total in 2010 to around 65% in 2022. In the EU, the sector accounted for roughly 26% of greenhouse gas emissions in 2022.
One reason for the slow uptake of green energy is that industrial processes run 24 hours a day. Switching from fossil fuels to electric boilers would mean relying on electricity bought from the grid, exposing factories to fluctuating prices. During peak hours, electricity costs can be four to five times higher than gas or fossil fuels — making industries heavily reliant on fossil fuels even in countries leading the way in electrification.
Yet industrial companies in the EU must reduce CO2 emissions. Arla, for example, has committed to cutting emissions in its supply chain by 63% by 2030. The company says it has already reduced its footprint by 37% but recognises that partnerships with innovative companies are “critical” to meeting its 2030 goals.
Relying on EU funding
Hyme’s project with Arla is now looking to secure EU funding of about €20m-30m. Once the funding is in place, the two parties will lay the groundwork for its implementation. The plan is to have the plant up and running by 2029. Since this is the first large project for Hyme, Benn says that for future projects the costs will go down, and “if we can get money from the EU, why not?”
For thermal energy storage solutions like this, cost savings are just as important as environmental benefits. Hyme believes its system can help decarbonise the industry while delivering significant economic advantages. If realised, the project is expected to save Arla €3m annually.
This project will be more or less fully owned by Arla when it is up and running and Hyme expects significant commercial revenue from it, but for other customers which may not have the capital or knowhow to invest and run something similar Hyme offers a heat-as-a-service agreement where it’ll raise capital from infrastructure investors to build and manage the plant and then charge the industrial customer a set energy price.
In 2023, Hyme raised €8m from existing shareholders Heartland A/S, Nordic Makers and North-East Venture and is now looking to raise another €20m to further develop its product. It also raised an equity fundraise of €10.4m in 2021 and has also secured grants of €10m.
Read the orginal article: https://sifted.eu/articles/five-years-after-cracking-cheap-solar-storage-hyme-plans-the-worlds-largest-thermal-energy-storage-system-news/
