Vatajankoski is a New Energy Company focused on renewable and combustion-free energy production. Starting in summer 2024, the company has met the entire summer district heating demand using waste heat recovered from a data center. Calefa’s AmbiHeat heat pump plant both processes the data center’s waste heat for the district heating network and provides cooling for the data center facility.
AmbiHeat® heat pump plant produces up to 2.6 MW of heat output from data center waste heat
Since summer 2024, Vatajankoski has been supplying the full summer energy demand of its district heating network with waste heat from the data center. This means providing heating for up to 400 properties and domestic hot water in Kankaanpää, a town in western Finland.
The data center has a capacity of 2 MW. When low-temperature waste heat is upgraded to district heating through the AmbiHeat® heat pump plant, the total output increases to 2.6 MW. The energy recovered from the data center accounts for 20% of Vatajankoski’s total district heating sales.
“In recent years, we have invested not only in renewables but also in combustion-free energy production methods. The data center and the AmbiHeat heat pump plant built alongside it have had a significant impact on our production profile.” – Lauri Hölttä, Production Director, Vatajankoski
Upgrading low-temperature data center waste heat into 85°C district heating water
After several years of planning, the data center began operating in June 2024 and has been operating at full capacity since then. At first, the company installed smaller water-cooled data centers at strategic points in the district heating network and customer sites to utilize the low-temperature waste heat.
Based on experience with these smaller data centers, the company opted for a larger data center sized to match the summer demand of the district heating network. Calefa and the AmbiHeat® plant were brought on board to upgrade the low-temperature waste heat into district heating water of up to 85°C.
A trusted partner for the data center project
Based on a successful collaboration in an earlier project in 2022, Vatajankoski saw Calefa as a natural choice for the data center project.
In 2022, an AmbiHeat heat pump plant was installed at the Kankaanpää Sports Center to provide cooling for the facility and recover surplus heat for the district heating network. The modular solution is housed in a separate container behind the sports center. Despite its compact size, the AmbiHeat plant provides sufficient cooling for a sports center of over 5,000 m², which includes a swimming hall, a sports hall, a gym, and other indoor sports facilities.
The first project marked one of Vatajankoski’s key steps toward fossil-free and combustion-free energy production. After the second project, more than half of Vatajankoski’s district heating now comes from various waste heat sources. This has further reduced the company’s CO₂ emissions from district heating.
“Calefa’s previous implementation and their expert solution for a similar data center project influenced our decision,” says Hölttä.
Read also about Calefa and MinersLoop’s data center project.
Smooth commissioning completes an innovative project
Hölttä is very satisfied with the collaboration with Calefa and considers the project an important step in reducing both energy production costs and climate emissions.
Together with the data center, the AmbiHeat heat pump plant allows Vatajankoski’s district heating customers to benefit from low-emission heating and stable pricing in the future.
In addition to these positive impacts, Hölttä was impressed by the quick and seamless commissioning of the new data center and the AmbiHeat heat pump plant.
“I was surprised by how short and painless the commissioning period was for the new plant.” – Lauri Hölttä, Vatajankoski
