Stockholm has the "Open District Heating" project doing that: https://www.opendistrictheating.com/ https://www.opendistrictheating.com/ (Disclaimer: I work for

Stockholm has the "Open District Heating" project doing that: https://www.opendistrictheating.com/ https://www.opendistrictheating.com/ (Disclaimer: I work for a company involved in this)