The examples are multiplying - as with heat pumps, which use 1 unit of electricity to produce 3-4 units of heat to supply the district heating:
Helsinki 🇫🇮 is a world leader, with a 500 MW seawater heat pump system under construction:
https://www.bloomberg.com/news/articles/2022-10-18/helsinki-utility-finds-a-surprising-heat-source-icy-seawater