The renowned thermal waters of Bath will bring warmth to the floor of the city's historic abbey, in one of the first "eco-friendly" projects of its kind globally.
Under plans, engineers will install heat exchange devices in a Roman-era drain carrying hot spring water to the famous Roman baths. They will transfer the heat into renewable energy.
Alix Gilmer from the Abbey told Premier: "It's very tried and tested technology. It's called a heat pump system. We've got some really good people working on it."
The work forms part of the £19.3 million Footprint project which will also see the dilapidated Victorian-era heating system ripped out and the crumbling floor replaced.
Alix Gilmer added: "In the centre of Bath, there's the Roman baths; the water from that goes in what was the old Roman drain through the city and down into the River Avon.
"So, it's not being used at the moment as a resource for heating in anyway."
An estimated quarter of a million gallons flows through the Roman baths every day.
It is hoped the scheme could eventually provide 1.5 megawatts of continuous energy - the equivalent of powering five hundred homes - to support a 200kW ground source heat pump system.
Photos from our exciting day yesterday when engineers from @isoenergy surveyed the Great Roman Drain to begin work on using hot water from the @RomanBathsBath to heat the Abbey. #Footprintproject https://t.co/fZFJaXvJuE pic.twitter.com/8bLhjTgCqg— Bath Abbey (@bathabbey) January 9, 2019
Engineers say disruption to York Street will be "minimal" while work to install the heat exchange devices underneath the road gets underway.
Click here to listen to Premier's Glyn Jones speaking with Alix Gilmer at Bath Abbey:
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