New technology has opened up for restaurants to finally start recovering the warm energy in their kitchen exhaust. The average annual incremental energy save per kitchen is 80,000 kWh, which not only helps restaurants cut down their energy bills, but they will also save 20 tonnes of fossil fuels and operating expenses.
Thermal energy in kitchen ventilation has always been considered waste – there has been no technology available to unlock energy recovery for these air streams, so the energy has been released straight out into the ambient air. This case study tested new heat recovery technology from Sweden with the aim to see if energy could be recovered robustly and profitably.
Kitchens produce pollutants like odours, soot, excessive heat and moisture. Overall, the typical kitchen exhausts around 1 cubic metre of air every second.
This energy output has always been seen as waste, but new technology can now transform this into a new source of energy to be re-inserted into the Kitchen.
The new heat recovery technology by Enjay was first evaluated based on data from other installations in multiple countries, and a simulation for the site was then made to get a figure of how much energy could be saved.
Subsequently, the technology was installed at a new Burger King restaurant in Welwyn Garden City. The data is being measured and gathered over a test period, with the team monitoring energy consumption at Welwyn against comparable restaurants in the wider estate to understand the impact of installing the system and therefore payback against the initial investment. Finally, the test data is being compared to the simulation data to verify how close the real-life data was to the simulated data.
According to the simulations, when thinking about the wider hospitality industry, the average energy per restaurant that could be recovered by the new technology is around 80,000 kWh. At the current energy rates, that adds a very useful annual cost save for the operator. And, as an industry, the UK hospitality could save 8,000,000,000 kWh every year, which equates to at least a saving of £2 billion that would also generate a reduction 2,400,000 tons of fossil fuels.