At this Rema supermarket in Trondheim, surplus heat generated by the refrigeration system is being stored temporarily in water tanks. The heat is then returned to the store via the ventilation and underfloor heating systems – when it is needed. This picture was taken on the day the supermarket opened. Credit: SINTEF
Waste heat and locally-produced renewable energy can be generated by compact, "urban power plants" that are efficient enough to supply heat to entire housing estates.
By supplying surplus heat, facilities such as freezers and IT server rooms can be transformed into compact "urban power plants." This energy, in the form of waste heat, can be distributed via so-called low-temperature district heating grids, also known as "fourth generation district heating." Such systems are currently being introduced as part of new housing projects.
This is good news for both the environment and energy consumption.