Y-Säätiö chose Voltan as their energy partner

Y-Säätiö selects Voltan as energy partner — geothermal heat-as-a-service for three large Helsinki properties

Y-Säätiö ran a competitive tender for heat-as-a-service geothermal providers in 2024. The goal was to determine whether geothermal as a service could deliver a technically sound, financially predictable and operationally hassle-free solution for a large residential portfolio.

The process began with a pilot at a smaller property. The pilot demonstrated in practice that service-model geothermal can offer property owners more predictable energy costs, lower CO₂ emissions and the ability to upgrade the heating system without the owner taking responsibility for the technical maintenance and performance of the system.

In spring 2025, we were selected as the service-model provider for three large residential properties in Helsinki. The decision was based on a thorough evaluation process that emphasised technical expertise, project management, risk management and lifecycle responsibility.

Y-Säätiö project manager Tuomas Ylä-Mononen describes the collaboration:

"Voltan's performance during the project was a positive surprise. The construction phase ran considerably more smoothly than in comparable previous projects, and disruption to residents was kept to a minimum. From the client's perspective, one of the most important successes was the clarity of the procurement process. With the service model, the entire scope — from design to implementation and maintenance — came through a single partner, which simplified decision-making and reduced the internal resourcing the project required. Procuring geothermal as a service was surprisingly straightforward from the client's perspective. Voltan's expertise was particularly evident in the way the project progressed as planned and the collaboration worked throughout."

The service model transfers risk away from the owner

Service-model geothermal means the heating system is not purchased as an asset but bought as a service — that is, as consumed energy. Voltan designs and builds the system, but also takes responsibility for the investment, operations, monitoring and performance throughout the contract period. For an organisation managing a large residential portfolio, this means stability both financially and operationally: the energy system is continuously monitored, optimised and under the partner's responsibility.

Transitioning to geothermal under a service model is a concrete example of how an energy system can be renewed without committing significant capital to an own investment. At the same time, technical and operational risk transfers to the energy partner, supporting risk management objectives and cash flow predictability.

Energy efficiency as part of a social mission

Y-Säätiö is one of Finland's largest non-profit landlords and a significant social housing operator. The foundation owns more than 10,000 apartments across Finland and provides affordable rental housing particularly for those in a more vulnerable position.

Y-Säätiö's decision to tender and pilot the service model reflects how energy matters are now being managed as a strategic whole rather than as an isolated technical procurement. With the service model, the client does not need to concern itself with optimising the system in existing apartment building stock.

When heating solutions are evaluated from a lifecycle perspective, the question is not simply about technology or a one-off equipment purchase. It is about a long-term partner capable of delivering both technical implementation and system performance for years to come.