Keeping the heat in
Published: 09 May, 2012
Retailers want to keep shop fronts open to invite potential customers into their stores. But this means heat can escape, costing money and increasing carbon emissions. Phil Chilton of Dimplex has a solution.
Open doorways can be a major challenge to energy efficiency in commercial premises, and air curtains offer the perfect solution, providing an invisible curtain of air to separate internal and external environments when access points are open. Installing air curtains can give a head start to reducing energy use by cutting a building’s energy consumption by up to an industry-recognised 30 per cent.
Phil Chilton, product manager for commercial installed products at Dimplex, says: “Air curtains have huge potential to cut carbon emissions when used with heating systems, and can have an even greater impact on energy use from air-conditioning systems. With businesses of all types, particularly retailers, under increasing financial pressure from tough trading conditions, and now the CRC Energy Efficiency Scheme adding to costs, air curtains can create high levels of savings for relatively little investment.”
Dimplex has a full range of air curtains that can all have a positive impact on carbon emissions wherever fitted, from the CAB and DAB ranges installed over doors of 3 m or 4 m, respectively, to the prestigious ARC designer models and heavy duty IAB range for large industrial premises.
|Air curtains can reduce energy consumption by up to 30%.|
To further reduce energy use, Dimplex air curtains are supplied with a built-in Building Energy Management System (BEMS) interface as standard and they can also be controlled via timers, presence detectors and temperature controls, which together improve the overall performance of a heating or cooling system.
A Clinton Cards retail outlet at Whiteley Village Outlet Shopping near Southampton noticed immediate benefits from the installation of a Dimplex CAB 1.5 m air curtain.
The store’s doors are open for at least eight hours a day, but the existing 12 kW air curtain was installed some distance inside the store and not directly over the door itself, meaning it wasn’t working efficiently to separate the indoors from the outside environment. To make up for this, the air curtain was running all the time during store opening hours, resulting in high energy usage.
A Dimplex 13.5 kW unit was installed to cover the entire width of the entrance and set for automatic selection of its “Eco” (6 kW) mode, and the default ambient setting, i.e. no heat. The thermostatically-controlled heating capability was only activated if the internal temperature dropped below the desired temperature.
For the 10-day test period in April, the thermostat was set to 21.5°C to achieve an average internal temperature of 20°C. With external temperatures varying from 12-17°C, on some days there was no requirement for additional heat to bring the internal temperature up to 20°C. In fact, on six of the ten days, the air curtain operated entirely on its ambient setting, effectively keeping draughts and external pollution out of the retail unit, but with minimal energy usage.
Energy costs for the test period were estimated at £13.50 (based on £0.10 per kWh), compared with the £96.00 which the previous 12 kW air curtain would have used. In terms of carbon emissions, based on an industry standard 0.51 kg CO2/kWh, the Dimplex air curtain delivered a carbon saving of 420.8 kg over the ten-day test period, with emissions of just 68.9 kg compared with an estimated 489.6 kg from the previous 12kW air curtain.
Keith Bray of Chertsey-based K&T Bray carried out the installation. “The important thing is to highlight to the customer that these air curtains are designed as energy-savers, rather than heaters. Fitted properly to completely cover an open doorway and used appropriately, they can make a real difference to a building’s energy use.”