Mills Group's main strategy to cut costs focuses on rolling out environmentally friendly chillers and heating systems.
The chillers are supplied by Franchill and use less energy than other units by utilising compressors more efficiently.
The retailer is looking into the possibility of using the chillers in at least half of its retail estate . The first is scheduled to be installed in a store in Doncaster on 28 August.
The move comes at a time when smaller retailers in particular are struggling with soaring utility bills - and highlights the fast-growing importance of green practices in the grocery sector.
Powering domestic and commercial fridges uses up to 25% of the national grid in the UK and can account for about 80% of a convenience store's energy bills.
Richard Linsell, group operations director at Mills Group, said: "The chillers only draw on the number of compressors needed at any one time and they use substantially less running power - a 30% reduction."
An added advantage of the chillers was they needed less maintenance, he said.
The chillers generate less heat than conventional units and so have the potential to shave substantial amounts off the cost of air conditioning, according to Franchill.
In addition, Mills Group has been working with The Frogbox Company to incorporate external heating units into stores.
The units work by using heat generated by the chillers to keep stores warm.
It is estimated that in some cases convenience stores have saved £1,200 to £1,300 on the annual cost of heating stores by installing the equipment.
Other retailers, such as Tesco and The Co-op Group, use the same heating method in some stores. Spar and Somerfield have installed Franchill chillers in stores.
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