Nando's recycles kitchen heat to warm water

The scheme has been rolled out to 14 more restaurants

A restaurant chain is using waste heat generated from its kitchen to heat water and buildings following trials.

The success of the year-long trial at Nando's Didsbury branch in Manchester has been rolled out to 14 other stores.

The system created by Lancashire energy firm Dext Heat Recovery uses a heat exchange - a box on the roof which collects the heat produced by cooking.

Instead of releasing it into the atmosphere, the heat is filtered and recycled.

Prof Karl Williams said he was "excited" by the development

Prof Karl Williams, director of the centre for waste and resource management at the University of Central Lancashire, said he was excited about ways to recover energy to combat the climate emergency.

"There's lots of technology out there to recover energy for example from sewers, but every bit helps to reduce our reliance on fossil fuels," he said.

Prof Williams added: "The main challenge I see with this is cost, to have a real impact it needs to go into smaller businesses on our high streets because there are a lot more of them than big chains.

"They'd find it difficult to invest as it would take them longer to get payback as they don't generate as much heat as larger chains."

The amount of heat produced in the average Nando's kitchen a year is enough to heat more than 30 homes for a year.

The heat exchange is on the restaurant roof

Neil Bracewell said it was a "game changer" for the restaurant industry

Dext has been working with Nando's since 2009 when they started collecting the heat from its grills to heat water- a system which is now used to save energy in 300 branches.

Heat recovery

Director of Dext Heat Recovery Neil Bracewell said he believed it could be a game changer for the restaurant industry.

"We work with Sheffield Hallam University where we developed and researched the heat exchanger to cope with dirty air from restaurant kitchens.

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"Nando's have helped us financially and by allowing us to test our equipment."

He added it was still a "learning curve", but they were "saving money and reducing CO2 emissions".

Sam McCarthy said Nando's was "keen" to share the technology

Mr Bracewell said their systems currently start at about £20,000 but estimated the outlay could be made back in 18 months depending on the size and use of the kitchen.

Sam McCarthy, Nando's head of sustainability for the UK and Ireland, said they were keen to share this technology with other restaurant chains.

"We have a net zero target of 2030 and this new technology is proving to be a success reducing the impact on the planet and saving money on energy bills which we want to reinvest in the future of our restaurants.

"We're always looking to trial new technology to help us with this and it's great to support and work with a small business like Dext."

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