About us

Polar Night Energy develops high-temperature thermal storage systems to reduce combustion, boost renewables, and combat climate change.

As featured in

Helping the world shift from fossil fuels to wind and solar power

Founded in 2018, Polar Night Energy is a Finnish company specializing in the design and manufacture of high-temperature thermal energy storage systems. Our mission is to reduce combustion in energy production and accelerate the expansion of wind and solar energy. 

Combining a simple yet ingenious concept with cutting-edge technology, the Sand Battery provides our customers with a cost-effective, sustainable, and reliable solution to reduce carbon emissions and maximize their use of renewable energy.

We help the world shift from fossil fuels to wind and solar power. We are the market leader in industrial-scale renewable energy storage solutions.

Key Figures

Company founded

Polar Night Energy was founded to decarbonize the energy sector.

Employees

Our team is focused on developing innovative energy solutions to fight climate change.

Technology readiness level

The Sand Battery is ready for commercial delivery, offering a proven, reliable solution for thermal energy storage.

Total funding

In 2024, we achieved a significant milestone by securing €7.6 million in seed funding.

Sand Battery projects

Sand Batteries are located in Tampere, Kankaanpää and Pornainen.

Founders

Polar Night Energy was founded in 2018 by Tommi Eronen and Markku Ylönen who first met in 2013 while studying at Tampere University of Technology. Tommi holds an M.Sc. in Power Plant Engineering, and Markku has a Ph.D. in Applied Mechanics.

”We saw the trend of declining electricity prices and increasing volatility a decade ago. It was clear to us that increasing renewable energy production won’t be enough to decarbonize the energy sector without high-capacity storages. We turned our idea of innovative energy storage into reality with very limited resources. The Sand Battery is the first of its kind and now ready for global deployment. Join us on our journey!”

Acknowledgements

According to Mission Innovation’s assessment, Polar Night Energy’s sand-based thermal energy storages may save over 100 Mt of CO2e per year in 2030.

Polar Night Energy was awarded an honorary certificate in the High Potential Carbon Handprint Innovation category at the International Carbon Handprint Awards 2022.

Junior Chamber International Finland selected the world’s first commercial Sand Battery as the Finnish Innovation of 2023.

The City of Tampere Technical Creativity of the Year 2022 Award was awarded to Polar Night Energy’s innovative way of storing renewable energy in sand.

According to the World Economic Forum, Polar Night Energy’s Sand Battery ”could help to solve one of renewable energy’s biggest challenges”.

Polar Night Energy was selected by One Initiative as one of the Nordic Top 50 Impact Companies in 2021.