Energy savings in display cabinets
Several new developments make it possible to save energy in display cabinets. - Optimizing air curtain velocity A team at the Air Curtain Research Laboratory at Kettering University in Michigan, US, has modellized the air flow in air curtains and air infiltrations behind them. The team discovered that the velocity of cold air sent into the cabinet could be reduced while raising the temperature of the air curtain. It was also shown that infiltration of warm air into the air cabinet could be maintained while lowering the velocity in the air curtain from 30 m/min down to an optimal 22 m/min. Decreased velocity surprisingly resulted in food being one degree colder as the cold air was distributed more evenly. Warm air infiltration was also reduced by 12%. Infiltration - which represents 83% of the cooling load - was reduced by 12% and power consumption by 13%. CCN World News, July 2009 - Automatic shutters ISA, a British cabinet specialist, is launching a multi-deck cabinet range with an innovative shutter device allowing for 35-40% savings over existing designs. The transparent shutter opens automatically when a customer approaches the cabinet and is activated by a movement sensor ("In-Touch") on the top of the canopy. A further sensor detects any resistance against the shutter as it closes, in case a product has been left blocking the shutter for instance. In-Touch technology has been shortlisted as a finalist in the Cooling Industry Awards 2009. RAC, June 2009 - Light Emitting Diodes LEDs are one of the most efficient and cost-effective sources of lights with fluorescent lamps (TL), but unlike the latter, they become more efficient at low temperatures, which makes them ideal candidates for freezer display cabinets. Less heat emissions from the light source result in additional energy saving in cooling: a 1 W reduction in input power of the light source will result in between 2.5 W and 4 W reduction in total power on average. Clients such as Sainsbury's have been realizing up to 70% energy savings on their frozen cabinet estate with a specific LED freezer module. RAC, June 2009