Sunday, May 3, 2009

The "Green" Future of Refrigeration

Over the last twenty years Hydrofluorcarbons (HFCs) have substituted the ozone depleting chlorofluorocarbons (CFCs) in refrigeration for their lower global warming potential. Still HFCs are powerful greenhouse gases when compared to fluids such as ammonia (NH3) or carbon dioxide (CO2). The combination of the natural refrigerant CO2with, for example, NH3 or propane, is a new development and currently practiced in several European countries.

Quite revolutionary in terms of refrigerant choice is the use of carbon dioxide (CO2)in supermarket refrigeration systems. The application of this natural fluid gas in combination with ammonia (NH3) has shown a large increase in the industry over the last few years. The two can replace environmentally harmful HFCs and are suitable as supermarket refrigerants.

Major advantages are a reduction of greenhouse gas emission by 40 per cent, when compared to HFC-use, and a 10 to 15 per cent lower energy consumption. Moreover, CO2 is a totally harmless refrigerant and absolutely safe in use. In spite of proven technology both retailers and installers are skeptical. According to TNO Environment, Energy and Process Innovation (TNO-MEP), a Dutch consultant firm, the benefits seem to be overshadowed by fear of an unfamiliar system with higher installation costs. However, stimulated by governmental subsidies the first supermarket refrigeration system in the Netherlands with only natural refrigerants has been established.

In March 2004, a store of the C1000-chain in Bunschoten introduced a so-called NH3/CO2-cascade system. NH3 is applied as a primary refrigerant for cooling and freezing, which is an innovative combination for supermarket refrigeration. Most experiments with CO2 in supermarkets in Europe have been restricted to CO2 in the freezing section. There is no doubt that the future of employment in this industry lies in the need to get the required education. Education should be a life-long process along with the pursuit of good health habits and proper exercise.

Roger J. Desrosiers

Roger has over 40 years experience in Air Conditioning and Refrigeration. He is also a member of R.S.E.S., CM, The Association of Energy Engineers, Certified Energy Manager, ASHRAE, Certified Pipe Fitter, United Association and is 608 Universal Certified. Roger is a contributing faculty member of