- Finnish deep-tech startup Granarium Technologies has raised over €1M in a pre-seed round led by BSV Ventures, with participation from Beamline, FiBAN, EstBAN, and LatBAN, to commercialise the world’s first renewable supercapacitors made from nanocellulose and waste biomass.
- The technology, developed at VTT, can lower supercapacitor production costs by up to 80% compared to traditional methods.
- CEO Paula Viinamäki, a former Nokia and Microsoft director who joined VTT as commercialisation lead to bring the technology to market, is targeting first pilots within six months across process industries and continuously running production operations.
Paula Viinamäki built her career at top European tech companies like Nokia and Microsoft, where she led product management, user experience, and Nokia’s Forward Labs. She later co-founded the Finnish SaaS startup Duuers and worked as commercialisation lead at VTT, Finland’s national research institute.
Instead of staying in software, she decided to focus on renewables at Granarium Technologies. She joined two VTT scientists, Otto-Ville Kaukoniemi and Vesa Kunnari, who discovered that electricity storage could be made entirely from renewable materials, found in abundance in Finland’s forests.
“Our approach supports Europe’s strategic goals of reducing dependency on critical raw materials and building local, resilient energy infrastructure. The new technology offers an easily scalable, self-sufficient solution that removes complex logistics chains and enables simple production using locally sourced materials. Deployment is as simple as installing a battery,” Viinamäki says.
The Finnish startup has raised over €1 million in a pre-seed round led by BSV Ventures, with Beamline and support from FiBAN, EstBAN, and LatBAN.
The science behind the materials
Nanocellulose, which comes from wood pulp, can bind biocarbon structures to store electrical energy. Granarium’s devices are supercapacitors, which are fast-response storage components that charge and discharge in milliseconds.
“Compared to lithium-based energy storage devices that utilise finite resources, our devices are far more environmentally sustainable as they derive from local and self-sufficient renewable carbon sources, and lower in cost to produce compared to battery gigafactory investments,” says Kaukoniemi.
The manufacturing process is different. Conventional supercapacitors, like those made by Skeleton Technologies, need complex chemical processing and expensive materials. Granarium’s nanocellulose-based platform makes production simpler and can lower capital costs by up to 80% compared to standard methods.
At first, commercial production will be limited to 50 units per year as a proof of concept and a base for future industrial partnerships. The company is still in the early stages of commercialisation.
Why now, and why the grid needs it
Grid volatility is already a major challenge across Europe. As wind and solar power grow, the grid faces more frequent instability and quick imbalances between supply and demand that need fast power injection or absorption within milliseconds. While batteries work well for longer storage, the market for short, high-frequency balancing is still underserved.
EU grid codes and resilience rules are getting stricter. Industrial operators with continuous production, such as paper mills, data centres, and pharmaceutical companies, are facing more power quality issues due to grid volatility.
Granarium’s supercapacitors offer a fast-response solution that complements batteries, handling millisecond-scale events that batteries cannot respond to quickly enough.
“A key structural shift is that storage is no longer just ‘backup power’ – it is becoming core grid infrastructure. Granarium is solving a massive global challenge in a safe and scalable way,” says Jana Budkovskaja, partner at BSV Ventures.
The pre-seed funding will support the first phase, with pilot projects starting within six months. The company also plans to expand into Germany and other international markets that have high grid volatility and strong industrial power quality needs.
