The new generation of intelligent controllers on refrigeration products can actually slice a considerable wedge from operating costs while keeping produce in optimum condition, as Kathy Bowry finds out.
Growing consumer interest in food provenance and local sourcing - driven by concerns about the environment as well as considerations for taste and freshness - means caterers are using increased volumes of fresh produce which, in turn, has led to a demand for increased refrigeration capacity.
However, as refrigerators use electricity day and night for 365 days a year the cost of running them is a huge strain on resources and has a negative effect on the bottom line. So what can be done to reduce the cost of intensively used refrigeration with incessant door opening and drawing back down to temperature while still providing the best storage conditions?
Plenty, according to Keith Warren, director of the Catering Equipment Suppliers Association (CESA), who says: "With the huge increase in energy costs, there is a big focus on energy efficiency and low power consumption. Smart controllers are a part of the solution - as they become more sophisticated, average energy consumption per cabinet should fall even more.
"Smart controllers reduce power consumption by adjusting to how hard the fridge is working," explains Warren. "Once the controller detects a change in the situation, it alters the way the refrigeration system operates to ensure that, while food is stored safely at the right temperatures, energy use is kept to a minimum. For example, if the door has not been opened for a given period of time, then the controller could switch off the evaporator fans. It'll carry on monitoring the temperature and, as required, switch the fans back on. This means that during quiet times - such as holidays or overnight - the refrigeration system will use less energy, while the smart controller ensures food safety and quality are protected."
Gram UK managing director Glenn Roberts says refrigeration manufacturers have been investing heavily in developing modern controllers that increase temperature control accuracy and improve operational flexibility.
"This can mean the same cabinet can store a variety of produce throughout its working week subject to the demands of the kitchen," he adds. "Having the technology to ‘read' the internal cabinet climate and regulate air flow and temperature levels on an ‘on demand' basis will ensure the optimum storage conditions and help to save energy costs."
Also forging ahead with new developments in controller technology is Foster Refrigerator. John Savage, foodservice director, says: "With running costs so high, it is of the utmost importance that food safety is not compromised by operators perhaps being tempted to raise temperature slightly in order to save money (commercial refrigerators should be between 0°C and 5°C). The use of intelligent controls ensures food safety is not compromised while providing the best storage conditions and better fuel efficiency.
"Using a ‘fuzzy logic' controller on our EcoPro range to measure coil and air temperature and monitor door opening and low energy fans which don't generate much heat, means they can turn in big savings," he says. "They also stop unnecessary defrosting by sensing when the coil is iced up and only doing it then instead of automatically as was the case in previous generations of cooling."
This point is picked up by Alan Evans, executive training chef at Electrolux Professional. "Most refrigerators defrost on average every four hours using a timed cycle, whether this is necessary or not," he says. "Our Smart Heavy Duty line of refrigeration uses sensors to detect ice in the evaporator to assess when to initiate a defrost cycle, ensuring that defrosting only occurs when it needs to. This means less defrosting and, as a result, greater energy savings, as well as improving the uniformity of storage temperature.
"For high capacity operators, such as prisons and catering colleges, the category function is an economical option available on our Smart refrigeration. This enables each fridge to be set to the correct humidity and temperature level for its contents, for instance, a meat fridge and a fruit and veg fridge."
Malcolm Harling, sales and marketing director, William's Refrigeration, has seen increased demand for refrigerated space over the past couple of years. "We used to supply more dual coldrooms (refrigeration and freezer) to commercial kitchens but recently there is more call for bigger chiller rooms as operators are promoting more seasonal produce on their menus," he says.
Like other major cooling manufacturers Williams has installed a new generation of intelligent controllers (Cool Smart) in its products, including coldrooms, which are claimed to contribute energy reductions of up to 15% by detecting changing situations and reacting by switching into economy mode in slack times and overnight.
The ‘next generation' of smart controllers is currently in development at British manufacturer Precision Refrigeration, says managing director Nick Williams. "These will minimise energy consumption by adjusting power requirement according to a variety of external factors, including door openings and ambient temperatures."
Matching cabinet temperature to food loads and product categories can also contribute to better energy usage. The Scanfrost Intelligent range from AHT Cooling features the Iridium Digital Controller which offers pre-set programmes with set points of temperature and humidity and the ability to vary the temperature/humidity within certain limits on individual programmes.
"The programmes allow the operator to easily change the temperature of the cabinet to suit the food types being stored, to ensure the temperature is not higher or lower than required," says AHT Cooling managing director John Lougher.
An internal humidity control, which is adjustable from 60% to 90% to ensure the ideal ambient temperature for delicate food, is a feature of the new Evolution 3 refrigerated cabinets from Friulinox. Easy-to-read panels and technological controls have been incorporated into the range which head of export sales Gianni Monai considers necessary adjuncts to ensure that chefs can easily see their refrigeration units are delivering hygienic and efficient performances.
"The self-diagnosis and function recording system prevents loss of efficiency of the refrigeration system and informs the user with a message on the display. It is this kind of sophisticated monitoring and controlling that is the future of refrigeration, minimising hygiene risks and ensuring energy efficiency," he says.
WAXING ON SAVINGS
But what about those who may not be in the market for new kit despite generous tax incentives offered by the Government Enhanced Capital Allowance scheme for operators stepping up to more ecologically sound kit? Paul Bracegirdle, environmental manager at Sodexo, thinks he has discovered the answer in a handy little device called the eCube.
eCube is a wax cube which can be easily fitted to a thermostat sensor. Instead of responding to fluctuating air temperature inside the cabinet, eCube reads food temperature only. By putting the temperature probe into the wax cube, which is like sticking it into a piece of meat in the refrigerator, the device measures the actual temperature of the food and stops the compressor switching itself on when it is not needed.
"We ran two double-door uprights for one week with eCube fitted and the next week without," says Bracegirdle. "The weeks with eCube gave us between 20% and 24% savings on those units. Fewer start-ups of the compressor to bring down temperature mean less fuel used and more money saved as it is the food temperature constantly being monitored."
David Bell, chief engineer at the Riverbank Plaza hotel, in London, is another eCube fan. He says: "After installing more than 150 eCubes, we are saving about £17,000 per year on our electricity bill. The eCube is being installed throughout the Park Plaza hotels in the UK."
AHT Cooling, 01280 826600
eCube Distribution, 020 8500 5033
Electrolux Professional, 0800 988 2809
Foster Refrigerator, 01553 691122
Friulinox/Frost Tech, 0845 290 3273
Gram UK, 01322 616900
Precision Refrigeration, 01842 753994
Williams Refrigeration, 01553 817000
KEY MAINTENANCE POINTS
Refrigeration breakdowns always increase when the weather get hotter. Here are six important things to do now to minimise the risk of breakdowns.
With greater throughput in the summer, train your staff to stack the fridges and freezers properly. Propping open the door of the fridge or coldroom is one sure-fire method of wasting energy and making the compressor work hardest. Do not stack boxes all round the evaporator, and don't fill a cabinet or bottle cooler so full that the air cannot circulate. Remember to chill bottles first before putting them in a bottle cooler.
Failure to keep the condenser clean will cost you about 8% in extra energy consumption. If you can see lots of fluff or dirt covering the components, have it properly cleaned by a service engineer. This will also help to stop the risk of overheating when it gets hotter.
A split door seal could cost you 10%-15% more energy. Split seals waste huge amounts of energy and you don't need that when kitchen temperatures soar. Wash all round the door seal with warm, slightly soapy water and a cloth. Don't use a knife. Check closely for splits or ill-fitting seals and replace if damaged.
If you have a coldroom, look closely at the evaporator, that's where the cold air is blown from. If there is any ice on it, or around it, particularly at the back or sides, there's a problem. If the ice has formed a stalactite, there's a bigger problem. You'll need a fridge service engineer to examine the cause.
Look closely at the ice from your ice maker. If it is usually clear, but has become cloudy, you may need to have the icemaker descaled. If you have a water filter fitted, change it at least once a year, and before the summer is a good idea. If you have a removable filter, pull it out and wash it thoroughly.
Check the temperature readouts of all cabinets at the end of a long shift; these will show if a cabinet is recovering temperature properly when used heavily. If they are not recovering the correct operating temperature - and especially if your fridges or freezers haven't pulled down to temperature after working all night - call an engineer immediately.
Source:Serviceline, 01438 363000