Cactos makes history on Finland's first congestion management flexibility market

June 7, 2026

In the beginning of June 2026, a milestone was reached in the Finnish energy market. The first ever trades were executed on FinFlex, and Cactos secured a capacity deal with Helen Sähköverkko Oy.

What is FinFlex?

In April 2025, the Finnish Energy Authority approved the conditions for FinFlex, a new TSO-DSO congestion management market operated by NODES. Helen Sähköverkko and Fingrid are piloting the market together in Helsinki for the first time, creating a marketplace where flexible resources can provide congestion relief to both distribution and transmission networks.

The logic is straightforward: instead of building more physical infrastructure to handle peak loads, grid operators can purchase flexibility through the market. Owners of flexible resources, such as battery energy storage systems, can sell flexibility to grid operators by adjusting their electricity consumption or production at the right time. This flexibility can be used to handle grid bottlenecks and prevent scheduled blackouts during grid maintenance.

What does this mean for Cactos customers?

Cactos operates energy storage that responds to grid signals almost instantly, making batteries one of the most effective flexibility resources available.

Through our deal with Helen, our customers are now actively participating in FinFlex. For example, an EV charging station in the Helsinki region is getting compensated for offering battery capacity to relieve congestion in the local distribution network.

New electricity markets like FinFlex demonstrate that the Finnish grid is evolving to meet the demands of an electrifying economy. We're glad to be part of it.

About Cactos

  • Founded in 2021 in Finland, Cactos manufactures and operates intelligent energy storage systems.
  • The company's name is inspired by a cactus, which adapts to its environment and excels at storing water and nutrients.
  • Revenue: €17 million
  • Employees: 100+
  • Has delivered energy storage solutions to over 400 sites across Finland, Sweden, the Netherlands, and Ukraine, with installed capacity exceeding 100 MWh.
  • Cactos systems manage peak consumption, secure critical power supply, and participate in electricity markets automatically.
  • Cactos also operates as an energy company, selling electricity directly to its customers.
  • Competitiveness is based on a full value chain approach. The Cactos Spine cloud service, developed in-house, maximises the value of energy storage for customers. Systems and key components are manufactured at the company's production facility in Kempele, Finland.
  • Cactos finances the majority of its energy storage systems.

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