A North of England convenience chain is to add doors to its dairy cabinets after trials revealed a dramatic improvement in energy efficiency with no impact on sales when doors were fitted.

The doors will be installed in 40 of Spar wholesaler James Hall's company-owned stores this year, in a move which the group says will generate huge long-term savings.

"Installing these doors means less power consumption, better temperature control and increased product life," said general manager store design and technical services Frank Frayling.

"The cabinet doors also mean air-conditioning systems don't have to work so hard at heating the stores, and the lack of a cold aisle means customers are likely to linger for longer and potentially buy more."

One trial store showed daily energy savings of nearly two-thirds on average, with a payback on investment of just over 12 months.

Cambridgeshire retailer Jonathan James has also seen a cost-saving from closed cabinets. "With open-deck chillers the running costs were £13,577 per annum, and for closed doors it was £5,393," he told Convenience Store. "It's a massive saving."