District heating pipelines are being connected to a block of flats under construction. The isolated pipelines bring overpressurized hot water from a central power plant producing both electricity and heat with a energy efficiency of approximately 90%. This kind of underground pipelines cover most of the Finnish cities. In addition to district heating, also district cooling services are available in some cities.
<a href="//commons.wikimedia.org/wiki/User:P%C3%B6ll%C3%B6" title="User:Pöllö">Pöllö</a>
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<span class="int-own-work" lang="en">Own work</span>