The combination of the recent climate conference in Copenhagen as well as ongoing climate-related legislation in the U.S., Congress has once again stirred up efforts of those who advocate hydrocarbons (HCs) and other natural refrigerants as long-term refrigerant options.

An organization called Hydrocarbons21 issued a statement in late December saying, “HCs have become a valuable alternative. [There is] the potential of opening up new market opportunities in the United States.” The natural refrigerant proponent added, “Until now only a few companies have taken the initiative to develop HC solutions for the U.S. markets.”

But it noted increased “interest in ‘green positioning,’ such as Ben & Jerry’s petitioning the U.S. Environmental Protection Agency (EPA) to be allowed to install its purified ice cream propane freezer design at 21 stores throughout the United States. This propane freezer design became the first hydrocarbon cabinet using propane listed under an amendment to UL 471 for flammable refrigerants in commercial refrigerators and freezers.”

Also the report said, “Taking advantage of the EPA’s Significant New Alternatives Policy (SNAP) program, General Electric (GE) petitioned for the approval of iso- butane (R-600a) refrigerant for use in its new Monogram brand refrigerator. If approved, GE plans to have these new refrigerator designs on the market by early 2010.”

Further, the report said, “Although the EPA SNAP program has not recognized the HC refrigerants for commercial or domestic products, Underwriters Laboratories (UL) has recently established a series of safety standards that now include HC refrigeration. This UL listing is a big step for the U.S.”

OBSTACLE

John Galyen, president of Danfoss Sales Americas, Refrigeration and Air Conditioning Division, highlighted some of the hindrances that hydrocarbons face in the United States.

According to Hydrocarbons21, they are:

• Charging and handling systems.“The EPA must determine whether natural refrigerants will have to be captured like synthetic refrigerants, or if a technician can safely vent the charge into the atmosphere. While some U.S. companies are experienced in handling HCs as a fuel, the HVACR OEMs will have to invest in technology to manage HCs moving forward.”

• Service and repair.“The industry will have to invest in training and certification to ensure safe and proper service and repair. This can be done through the Refrigeration Service Engineers Society (RSES). However, there will likely need to be some form of training requirements and certification to drive widespread adoption.”

• Compressor concerns.“Propane is used with POE oil in Danfoss compressors. Material compatibility is almost identical to R-134a or R-404A. Isobutane is most often used with mineral compressor oils. Material compatibility is almost identical to R-12.”

• Purity.“For an HC product to be UL listed, it must meet the requirements of a classified refrigerant, which means a base purity of 99.5 percent and a water content that does not exceed 25 ppm. Purification is not a major obstacle as hydrocarbon refrigerants are not patented, which assures OEMs and end users that supplies will be affordable.”

• Component cost.“Component manufacturers are already developing 220-V, 50-Hz products for HC systems for Europe and other global markets, including some 115-V, 60-Hz versions for certain Latin American markets. Therefore, manufacturers can readily extend their portfolios to include units for the U.S. without significant investments.”

THE CHANGEOVER

On a broad base, the natural refrigerant advocate Eurammon issued a statement saying, “System operators should use the opportunity posed by the 2010 phaseout of HCFCs to change over to natural refrigerants such as ammonia, carbon dioxide, or hydrocarbons.”

Monika Witt - chair of the organization, which is made up of companies, institutions, and individuals - said, “Even though systems with natural refrigerants may entail higher initial costs, when viewed over the entire life cycle, the costs are lower than in systems that use synthetic refrigerants.”

She noted, “Thanks to their higher energy efficiency, ammonia is deemed to be the most efficient refrigerant of all. These refrigeration solutions need less power and will have paid for themselves within just a few years.”

She added, “Carbon dioxide is frequently a good choice at very low temperatures, while ammonia is particularly suitable for industrial purposes above –35°C.

“Propane is the refrigerant of choice in the chemicals industry and increasingly in supermarkets and is ideal for use upwards of –40°C.

“Furthermore, various mixtures can also be used such as the azeotrope R-723, which consists of ammonia and dimethyl ether. This permits the use of air-cooled condensers at even higher ambient temperatures.”

For more information, visit www.hydrocarbons21.com and www.eurammon.com.

Publication date:02/01/2010