"..cold river water from the Seine is pumped through one pipe, which runs right next to a secondary pipe carrying warm water from the city’s buildings. A thin metal wall separates them and a heat exchanger allows the heat from the warm city water to enter the cold Seine water without the fluids ever touching"

#Paris #Heat #ClimateEmergency #DistrictCooling

‘Kind of miracle solution’: How Paris is harnessing the Seine to replace air-con | Extreme heat | The Guardian
https://www.theguardian.com/environment/2026/jun/26/underground-revolution-seine-cooling-network-paris-buildings-heat

While Helsinki isn't exactly experiencing a heatwave currently, we do have some hot spells occasionally. That's why we've built multiple cold water reservoirs under the city over the decades.

Here's one under the very city centre:

https://helij.wordpress.com/2019/11/25/something-surprising-underneath-the-esplanade-park-in-helsinki/

https://yle.fi/a/74-20174567 "Underground 'lake' helps cool Helsinki as demand for district cooling rises"

#districtcooling #energy #greenenergy

#Helsinki energy utility Helen invests100M€ (incl. 14M€ govt. grant) in new #heatPump to produce 90MWth #DistrictHeat and 60MWth #DistrictCooling.
Heat source is wastewater, that has already delivered heat to the #KatriVala heat pump station, but with heat remaining.

Heat pump should be operational in late 2025 and deliver 460 GWh/a heat.

Too bad #SeasonalStorage is not included in this project, that could add value when power price volatility increases.

https://www.helen.fi/uutiset/2022/tyo-ja-elinkeinoministerio-on-myontanyt-investointitukea-helenin-uudelle-eiranrannan-lampopumppulaitokselle