Close this search box.

Waste heat from a data centre replaces fossil energy

Espoo will soon be the site of a giant leap towards carbon neutrality. Several parties are working together to put the green transition into action by harnessing the waste heat from a data centre to heat buildings.

Some ambitious targets are in place for carbon neutrality: Finland aims to become carbon neutral by 2035, and Espoo, the country’s second-largest city, is trying to get there by 2030.

Before Espoo and its 300,000 residents can reach this target, fossil energy needs to be eliminated from district heating production. Fortum has promised to do this by 2029. It has also set itself the milestone of
stopping the burning of coal at the Suomenoja thermal power plant by 2025.

A solution has been developed to help Fortum reach this goal, exploiting heat that has, until now, been an undesirable by-product.

“Data centres can be built in urban areas. They generate a lot of waste heat, which can be used in combination with CO2-free electricity to provide district heating for citizens,” says Antti Kaikkonen, Project Development Director at Fortum.

In practical terms, the waste heat is harnessed by sending the indoor air from the data centre through a heat exchanger, which transfers the thermal energy into water flowing in a closed loop to a heat production plant. The plant transfers the heat into the district heating system, which sends it onward to thousands of homes and workplaces.

Fortum aims to use waste heat from data centres to cover 40 per cent of the heat production in its area by the end of the decade.

Fortum aims to use waste heat from data centres to cover 40 per cent of the heat production in its area by the end of the decade. This could reduce carbon dioxide emissions by approximately 400,000 tonnes a year. 

The benefits actually accrue in multiples as Finland gains data centres, jobs and wellbeing at a stroke. Furthermore, coal purchased from foreign countries can be replaced by clean domestic energy, making Finland less dependent on imports.

The decision was taken to build a data centre in Hepokorpi, Espoo, as the area is close to both the district heating and electricity networks.

“The entire project relies on the construction of a new substation near the data centre. Fingrid’s new substation will serve the upcoming data centre while enhancing the electricity supply throughout Espoo as it continues to grow,” Kaikkonen says.

Using emission-free elevtricity as an incentive

Fortum set out to identify a partner for the data centre project that is compatible with Microsoft’s goals.

“Sustainability is one of the most important drivers of Microsoft’s business. The company has set itself the target of becoming carbon negative by 2030. That is why it is so important for us to have access to a reliable supply of CO2-free electricity,” says Patrik Öhlund, Director, Energy Markets at Microsoft.

Microsoft considers Finland a good place to invest and is establishing new data centres in Kirkkonummi and Vihti in addition to the one in Hepokorpi, Espoo.

Microsoft considers Finland a good place to invest and is establishing new data centres in Kirkkonummi and Vihti in addition to the one in Hepokorpi. These will supplement its global cloud infrastructure, which currently has more than 60 data centre regions and over 200 data centres. These serve more than a billion customers in 140 countries.

“When we evaluated where to invest, one of the central factors was Finland’s very stable and reliable power system. Furthermore, as Microsoft is committed to using 100 per cent renewable energy at its data centres, the fact that significant renewable energy production capacity will be built in Finland in the coming years was also important,” Öhlund says, praising the Hepokorpi data centre project as a very innovative idea.

Increasing consumption requires investment

When Fingrid’s substation is built in Hepokorpi along with Microsoft’s data centre and Fortum’s heat pump plant, the entire project will be in final, functional order.

The design focuses on ensuring that the building blends into its urban environment, and, to this end, timber construction will be one of the methods used. The substation will also have environmentally friendly ester oil transformers.

“Espoo’s high-voltage network will require substantial reinforcement as the energy revolution causes the required electricity capacity to soar. At the moment, Fingrid’s Espoo substation supplies all the electricity for Caruna’s network. The new Hepokorpi main grid station is an important step in boosting the capacity distributed around the Espoo region,” says Jukka Ihamäki, Regional Director at Caruna.

He points out that digitalisation and the green transition mean that many functions will be electrified.

“Electricity consumption is expected to increase dramatically in Espoo by 2030 due to heating, transport and also digitalisation. In the latter, data centres are the largest and most visible consumer,” Ihamäki says.

However, not all the electricity consumed by data centres should be counted as additional to the previous electricity consumption: companies and organisations are moving their ICT systems out of on-premises data centres and into energy efficient cloud services.

The rapid change also requires Caruna to invest tens of millions of euros.

The rapid change also requires Caruna to invest tens of millions of euros. One of the most important projects is a cable link from Hepokorpi to Finnoo, which will ensure the supply of electricity to South Espoo.

The urban environment poses challenges of its own, as construction work must be reconciled with the existing infrastructure, urban fabric, nature and the future plans for a growing city.

Challenges of the permit system

All the parties in the Hepokorpi project emphasise the importance of a smooth permit process so that practical progress can be made towards the carbon neutrality goals of Espoo and Finland, and companies are encouraged to invest.

The schedules are already tight due to the planning and construction alone, and the permit practices, with all the potential appeals, present an additional challenge.

“There are no shortcuts in the permit process, but it would be helpful if the excess delays could be eliminated. This would make the situation much easier, and we could get society electrified more quickly,” Ihamäki emphasises.

He considers the Hepokorpi project an example of how Finland is an attractive country for foreign investors with its reliable supply of CO2-free electrical energy.

“We should capitalise on the energy revolution and green transition that are now in train and boost employment and wellbeing in Finland.”


Leave a Reply

Your email address will not be published. Required fields are marked *