Maggad Khalidy points to a big metal box on the roof of a Burger King in Malmö, southern Sweden, surrounded by pipes and wires.
Although it may not seem like a revolutionary invention, the large metal box on the roof of a Burger King in Malmö, southern Sweden has saved the franchise around $16,000 (£13,000) a year in heating bills, according to Maggad Khalidy, the franchise owner.
Enjay, a start-up from Malmö, has developed a new type of heat exchange equipment called Lepido that recovers energy from kitchen fumes to heat other areas inside restaurant buildings, reducing bills for conventional heating and emissions.
After being chosen for Enjay’s pilot project in 2016, Mr Khalidy, the owner of a Burger King franchise in Malmö, had initial doubts about the Lepido technology. However, he has since seen substantial savings and a fast return on investment.
Enjay claims to have developed the world’s first profitable energy recovery product from contaminated kitchen exhaust air.
Its patented product, Lepido, has been commercially available since 2018 and has been installed in approximately 250 Burger King franchises across Sweden, Norway, and Denmark, as well as other commercial kitchens in the Nordics and Benelux.
Despite minimal marketing outside the Nordics, the company is receiving an increasing number of inquiries from restaurateurs in Europe, Canada, and the US amid the global energy crisis.
Enjay has begun trials in various UK locations, such as a Burger King in Welwyn Garden City and Turtle Bay restaurants in Salford Quays and Brindleyplace.
Matt Mansfield, facilities manager for Turtle Bay, says the results of Enjay’s trials in Sweden impressed him, and the company is looking for ways to become more sustainable and reduce costs.
According to Arne Speerfork, a professor specializing in thermodynamics at Hamburg University of Technology, heat exchange systems that transfer warmth within a building are already widespread in many sectors, but recovering energy from commercial kitchens poses a challenge.
The hot air in kitchens contains grease and soot particles that cling to conventional heat exchange technologies, making heat recovery difficult.
As a result, the hot air generated during cooking is often directly vented outside restaurant buildings.
Enjay’s Lepido technology is designed to prevent grease and soot particles from sticking to the metal coils inside, which is a common problem with traditional heat exchange systems, explains Arne Speerfork, a thermodynamics professor.
Instead, the hot air is pumped over pipes carrying cold water, which warms up and can be used to heat other parts of a building.
While effective, the average cost of $30,000 (£24,000) for a Lepido heat exchanger may be a challenge for smaller independent restaurants, though Enjay’s Nils Lekeberg argues that most businesses should recoup their investment within a year or two.
Source : bbc.com