Ilmatar and Polar Night Energy Join Forces to Store Excess Wind and Solar Energy in Large-Scale Sand Batteries


Polar Night Energy is developing the world-renowned Sand Battery towards Power-to-Heat-to-Power (P2H2P) capabilities – a cutting-edge system that converts excess renewable energy into heat, then back into electricity. The company will start a two-year program of development and commercialization of its electricity production capabilities.

Ilmatar, one of the leading IPPs in the Nordics, will participate in the development and will be among the first to be offered these state-of-the-art large-scale P2H2P systems. Ilmatar will provide Polar Night Energy with commercial piloting opportunities on their wind farms when the technology reaches an advanced stage. This will mark a significant step toward the practical deployment of this innovative solution.

“Renewable energy production business has finally reached the volume level where we can focus more on the cost-efficient, large-scale and flexible energy storage”, says Ilmatar’s New Business Development Manager Katja Koponen.

The collaboration aims to boost wind and solar power profitability and, at the same time, promote innovation in the energy storage sector.

A well-known challenge of weather-dependent energy production is that electricity market prices are often low when production is at its peak. By developing new high-capacity energy storage solutions, the companies are building flexible and decentralised energy system of the future while also creating new business opportunities and addressing bottlenecks in electricity transmission.

“Installing energy storage behind the meter at a wind farm makes controlling electricity output to the national grid easier. Similar advancements will follow with solar power as its grid presence grows. These large-scale storage solutions are crucial in our long-term strategy for cleaner energy,” says Markku Ylönen, CTO of Polar Night Energy.

“We highly respect Ilmatar and are thrilled to collaborate. Ilmatar’s exclusive focus on wind and solar, without any history of combustion-based production, aligns with our vision. Being acknowledged as a key technology partner by Ilmatar, who are one of the leading players of future energy companies, is an honor,” he adds.

Polar Night Energy and Ilmatar are committed to exploring the most effective methods for integrating Polar Night Energy's thermal energy storages into Ilmatar's wind and solar installations and drive the transformation of the renewable energy landscape.

Ilmatar's Project Developer Samuel Heino and New Business Development Manager Katja Koponen with Polar Night Energy's CTO Markku Ylönen and Project Manager Liisa Naskali (from left to right) at Ilmatar's Humppila-Urjala wind farm. PHOTO: Marjaana Malkamäki