Shared and district heat reuse
One site's waste heat warming others: data centres, sewers, metros, factories, supermarkets.
Recovery and reuse · Shared heat and everyday recovery · No. 137
- Recovery and reuse
- Heat grade: Low
In Finland, heat from Microsoft's data centres now warms homes, supplying about 40% of a 2 TWh city heat network.
Chart: Illustration: Shared and district heat reuse
Where it comes from
Chart: Map of where it comes from
Shared heat schemes collect lukewarm heat from data centres, treated sewage, metro tunnels or factories and lift it with big heat pumps into district heating pipes.
Three things to know
- German data centres turn more than 13 TWh of electricity a year into heat, most of it simply thrown away.
- EU rules now require data centres above 1 MW to use their waste heat unless shown not feasible.
- Helsinki's Katri Vala plant sells both heat and 100 MW of cooling, helping it run about 6,250 full-load hours.
The journey
- 1 Lukewarm sourceData centres, sewage, metros, factories
- 2 Heat captureExchangers collect heat at 25-40 C
- 3 Heat pumpElectricity lifts it to network temperature
- 4 District networkUnderground pipes carry hot water to buildings
- 5 Homes, officesWarmth in winter, sometimes cooling in summer