Cactos is a Finnish energy technology company that designs, manufactures, and operates intelligent battery energy storage systems (BESS) for commercial, industrial, and grid-scale customers. Founded in 2021 in Northern Ostrobothnia, Finland, the company builds its systems — from battery modules to its proprietary Cactos Spine cloud software — at its factory in Kempele. Its products enable load shifting, peak shaving, solar energy storage, backup power, and participation in electricity reserve and wholesale markets, all managed autonomously without customer intervention.

Cactos initially gained attention for repurposing second-life Tesla EV batteries into energy storage units, reducing upfront costs and supporting circular economy principles. The company has since expanded to incorporate new battery modules as well, and now offers a full-service model covering financing, installation, optimization, trading, and monitoring. Its grid-scale platform, Cactos Nevado, is designed for large multi-site battery portfolios. Cactos also operates as a licensed energy company, selling electricity directly to customers in Finland.

With 300+ installed systems and 100+ employees as of 2026, Cactos serves logistics centers, manufacturers, EV charging operators, farms, and real estate investors across Finland, Sweden, the Netherlands, and Ukraine. The company quadrupled revenue for two consecutive years, reaching €17 million in FY2025. Its largest contract to date covers a 34 MW / 89 MWh portfolio across five grid-scale sites in Finland. Cactos has offices in Helsinki, Kempele, and Amsterdam.