90-GWh thermal energy storage facility could heat a city for a year
Some cool green engineering:
The project has a total volume of 1.1 million cubic meters (38.85 million cubic feet), including processing facilities, and will be built into [Vantaa]’s bedrock at around 100 m (330 ft) below ground – though the deepest parts of the setup could go down as far as 140 m. Three caverns will be created, each measuring 300 m (984.25 ft) in length, 40 m (131.2 ft) in height and 20 m (65.6 ft) in width. These will be filled with hot water by a pair of 60-MW electric boilers, powered by renewables when it’s cheap to do so. Pressure within the space allows for temperatures to get as high as 140 °C (284 °F) without the water boiling over or steaming away. Waste heat from industry will also feed the setup, with a smart control system balancing energy sources. The Varanto facility is reported to have a total thermal capacity of 90 GWh when “fully charged” – enough to meet the year-round domestic heating needs of a “medium-sized Finnish city.”
(tags: engineering finland district-heating energy energy-storage caves cool)