Estonia has successfully leveraged its digital expertise to drive innovation in the physical realm of climate technology. The nation now produces deep-tech companies that address the most challenging challenges in materials science and energy infrastructure. Founders here do not just build tracking apps. They engineer the batteries, grid systems, and sustainable materials required for a carbon-neutral future.
The ecosystem combines Nordic design sensibilities with industrial-grade engineering. These startups are turning waste streams into valuable resources and converting CO2 into critical battery components. Here are the 10 Climate and ESG startups in Estonia you need to watch in 2026.
Skeleton Technologies
Taavi Madiberk and Oliver Ahlberg founded Skeleton Technologies to solve the power density limitations of lithium-ion batteries. They manufacture ultracapacitors using a proprietary curved graphene material that enables charging in seconds. The company has raised over €300 million and partnered with Siemens to build the largest supercapacitor factory in Europe. Their technology captures wasted energy from heavy machinery and trams, instantly redeploying it to meet peak power needs.
Sunly
Priit Lepasepp founded Sunly to accelerate renewable energy production across the Baltics and Poland. The independent power producer develops solar and onshore wind parks with a strong focus on community involvement. Sunly raised significant capital in 2024 to integrate battery storage directly into its generation sites. This strategy stabilises the grid and demonstrates that decentralised developers can deploy renewable infrastructure more quickly than state-owned utilities.
Single.Earth
Merit Valdsalu and Andrus Aaslaid created Single. Earth to align financial markets with planetary health. The platform tokenises the ecological value of forests, such as carbon sequestration and biodiversity. It pays landowners to preserve ecosystems rather than harvest timber. The system uses satellite imagery and AI to verify the condition of the forest in real time. This approach creates a nature-backed digital currency that rewards conservation directly.
Woola
Anna-Liisa Palatu founded Woola to replace plastic bubble wrap with a sustainable alternative. The company utilises waste sheep wool that would otherwise be burned to create shock-proof packaging envelopes. Woola supplies major e-commerce retailers and luxury brands, such as Madewell, with compostable shipping solutions. The business model addresses two key issues by reducing plastic pollution and generating a revenue stream for sheep farmers who struggle to sell coarse wool.
Roofit. solar
Andri Jagomägi founded Roofit.solar to integrate solar energy generation directly into building materials. The company manufactures steel roofing modules with photovoltaic cells embedded inside the metal. The product generates electricity while maintaining the aesthetic look of a traditional Nordic black metal roof. This building-integrated photovoltaic solution appeals to homeowners who want energy independence without mounting bulky panels on top of their homes.
UP Catalyst
Gary Urb founded UP Catalyst to localise the supply chain for electric vehicle batteries. The company uses a molten salt electrolysis process to capture CO2 emissions from heavy industry and convert them into carbon nanomaterials and graphite. These materials are essential anodes for batteries. The technology creates a circular carbon cycle, reducing European reliance on imported battery raw materials from geopolitically unstable regions.
eAgronom
Robin Saluoks built eAgronom to provide a financial incentive for sustainable farming. The platform initially launched as farm management software but now operates as a carbon credit engine. It helps farmers implement practices like cover cropping and verifies the resulting soil carbon sequestration. Farmers can then sell these high-quality credits to offset buyers. Backed by investors like Swedbank, the company provides the capital bridge necessary for agriculture to transition to regenerative methods.
Reverse Resources
Ann Runnel founded Reverse Resources to close the loop in the global fashion industry. The SaaS platform tracks textile waste from garment factories to recycling plants. It provides visibility into the supply of leftover fabric, which allows major brands like H&M to source recycled materials effectively. The digital tracking system ensures that waste is actually recycled rather than dumped. This transparency is crucial for fashion brands as they navigate the implementation of new EU regulations on textile waste.
R8 Technologies
Siim Täkker founded R8 Technologies to reduce energy consumption in commercial real estate. Their AI engine connects to existing HVAC systems in large buildings to optimise heating and cooling automatically. The software adjusts settings in real-time based on electricity prices and weather forecasts, eliminating the need for human intervention. The system manages over 3 million square meters of commercial space and typically reduces energy costs by approximately 20%.
Grünfin
Triin Hertmann and Karin Nemec created Grünfin to simplify sustainable investing for retail users. The platform builds portfolios of ETFs that strictly comply with the highest EU sustainability standards. It filters out greenwashing to ensure capital flows to companies with genuine impact. The service enables individuals to grow their savings while supporting causes such as climate change mitigation and gender equality.