Stationary air conditioning systems are used to provide cooling for indoor occupants for their thermal comfort at a suitable indoor air quality. Within the cooling sector the stationary air...
The commercial refrigeration sector comprises the equipment, technologies and services used to store and dispense frozen and fresh foods at the appropriate temperatures. This sector includes stand-alone or self-contained systems, condensing unit systems, and centralised or ‘multiplex rack’ systems. According to the 2010 assessment of the Montreal Protocol advisory panel, the Technology and Economic Assessment Panel (TEAP) Technical Option Committee, these categories were estimated to contribute 7%, 47%, and 46% respectively to the total quantity (or ‘refrigerant bank’) of refrigerant used in 2006.
The special report of the Intergovernmental Panel on Climate Change (IPCC)/TEAP indicated that on a global basis, commercial refrigeration is the refrigeration subsector with the largest CO2-equivalent emissions, representing 40% of total annual refrigerant emissions. These emissions are categorised as direct and indirect emissions. Direct emissions refer to emissions of the refrigerant itself during system manufacturing, operation, and disposal at end-of-life. Indirect emissions refer to the emission of carbon dioxide and other greenhouse gases (GHGs) that result from the energy consumption (usually electricity) of the system over its lifetime.
Reducing leakage rates through better design and installation practices will reduce direct emissions. As reported by the IPCC, the refrigerant emissions might represent 60% of the total emissions of GHGs resulting from system operation, the rest being indirect emissions generated by power production. A higher Coefficient of Performance (COP = heat removed/ required work) for the refrigerated system will help in reducing the indirect emissions since the amount of work required to remove the heat will decrease.
Meanwhile, the transport refrigeration sector comprises the equipment, technologies and services used to transport and dispense frozen and fresh foods at the appropriate temperatures. Travel time, ambient temperatures, and risk of spoilage often make temperature controlled transportation necessary. Because some commodities are sensitive to the relative humidity and chemical composition of their surrounding atmosphere, these conditions may also need to be controlled. Today many commodities travel to distant markets intermodally (i.e., by some combination of highway, ocean and railroad).