Appliance Design - April 2008 - (Page 33)

COOLING TECHNOLOGIES the best refrigerant in the long-term. In efficiency testing, natural refrigerants did better than they initially expected, says Jacob. He says that the CO2 systems compared to the HFC systems were 4 to 7 percent better. Their testing found that CO2 systems work better at somewhat lower ambient temperatures, below 35 DegC, than did the HFC systems. While Coca-Cola chose CO2, Unilever chose the hydrocarbon, propane. In 1994, Unilever, one of the world’s biggest ice cream manufacturers, was one of the first company’s to transition to HFC-based freezer cabinets and have already moved to phase these systems out. By the end of 2007, about 200,000 hydrocarbon-based freezer cabinets were installed throughout Europe. According to the company, lab tests suggest these hydrocarbon cabinets are energy efficient, using up to 12-17 percent less energy than previous units. According to Alan Gerrard, Unilever’s Global Project Leader for this project, field-testing showed efficiency gains of around 9 percent. While the company had planned all along to phase out HFCs, it was uncertain about which natural refrigerant to choose. After testing many alternatives, they decided to back propane for a couple reasons. As an economic decision, they chose propane because at the time there were a large number of low-cost compressors on the market that could handle the natural refrigerant as compared to CO2 compliant compressors, which were not as available and cost more. The second, more important reason, dealt with thermodynamics. Gerrard says that to reach the operating temperature that they require (–18 DegF) using a CO2 system would have meant using two compressors in order to reach the same energy efficiency as the hydrocarbons. When choosing propane, they were initially concerned about safety issues. “The first question we had was the flammability of the refrigerant,” he says. “But, we knew that isobutane and propane have approximately the same flammability rating and that in the year 2000, there were about 120 million domestic refrigerators and freezers using isobutane and we weren’t aware of any accidents.” Unilever undertook a number of risk assessments before the introduction of the hydrocarbon cabinets. The company also did leak testing and found that the leak rates for hydrocarbons in operation were “very, very low,” he says, in line with HFC refrigerated cabinets.. Leak rates are in the range of grams per year, he says, and at this rate it was highly unlikely that flammable mixtures could be formed. Unilever’s environmental work is not just a www.applianceDESIGN.com AD04084Foam.indd 1 matter of good citizenship, but economics and it may point to a new paradigm for the industry – making design and engineering decisions based on the impact of a consumer’s awareness of how well a company acts as an environmental steward. “In the early stages of the program, the consumer was less strongly in mind,” says Gerrard, “But it has become clear to us that consumers are demanding more from our products than just quality and value, they are also looking for com- panies that are aware of their impact on society and the environment.” < For more information, enter numbers: Arkema Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306 Or email: stan .howard@arkema .com DuPont Refrigerants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 Or email: Ellen .G .Pressley@usa .dupont .com Ineos Fluor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308 Or email: KleaUSwebmail@ineosfluor .com For more Information Enter 111 applianceDESIGN April 2008 33 3/7/08 10:40:26 AM http://www.ecomatesystems.com http://www.ecomatesystems.com http://www.appliancedesign.com

Table of Contents Feed for the Digital Edition of Appliance Design - April 2008

Appliance Design - April 2008 Contents Editorial Shipments/Forecasts News Watch A Variant of Thermoacoustic Refrigeration Known as Acoustic-Stirling is Expanding Its Range Outside Cryocooling Into More Conventional Applications Such As Refrigeration and Air Conditioning Free-Piston, Stirling Coolers Are Now Showing Up in Mainstream Applications As Costs Come Down and Heat Transport Solutions Are Devised Heat Exchanger Innovations Are Helping To Improve the Overall Efficiency of Vapor Compression Systems Environmental Concerns Have Once Again Ignited a Debate Over Refrigerants A New Glass Ceramic Material for Induction Cooktops Can Be Decorated In a Variety of Glimmering Metallic, 3-D Looks That Can Employ a Number of Shades, Patterns, Styles, Colors, Intensities, and Textures Colorful, Reflective Coatings for Glass Create a Variety of Design Options To Help Designers Establish a Unique Look for Their Products Appliance Designers Faced With Different Motor and Drive Options Need To Understand the Differences and Tradeoffs Before Choosing A New MEMS Valve Offers a Number of Advantages Over Solenoids In Certain Applications, Including the Opportunity To Cut Energy Use The AHR Expo Set Attendance Records and Showcased Thousands of Innovative New Products Classifieds Design Marts Advertiser’s Index Association Report: CEA

Appliance Design - April 2008

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.