Page 3 OZONE LAYER Ozone (O3 ) is a gas composed of three oxygen atoms. 90% of the ozone is found in the upper atmosphere, 10-50km above earth surface (stratosphere). The ozone layer absorbs most of the harmful ultraviolet-B (UV-B) radiation from the sun. CFCs and HCFCs link to ozone layer depletion. If the ozone layer depletes, more harmful UV-B radiation will reach the earth through the damaged ozone layer. Ecological damages and health risk.
Page 6 In 1985, British scientists discovered a large thinning in the ozone layer over the Antarctic continent. In September 1998, the Antarctic ozone hole reached a record size of 25 million km 2,or two and half times the size of Europe. UV-B levels are now about 7% higher than thirty years ago.(1970s) UV-B radiation has increased dramatically nearer the poles, 22% higher in the Arctic and 130% higher in the Antarctic relative to values in the 1970s. OZONE DEPLETION Source: American Chemical Society [August 29, 2011]
Page 11 1.Developed under the United Nations Environment Programme (UNEP) in 1987. 2.Objective is to protect the Ozone layer by phasing out the production of numerous Ozone depletion substances. 3.Requirement to phase out CFCs in year 1996 and HCFCs in year 2030. 4.In Malaysia, CFCs total phase out in year 2010. HCFCs total phase out in year 2040. MONTREAL PROTOCOL
Page 13 World Top Ten GHGs Emitters (2010) KYOTO PROTOCOL Source: BP, Statistical Review of World Energy (London: June 2011)
Page 14 To phase out R22, alternatives to R22 should be chosen carefully though overall evaluations: 1.Energy efficiency 2.Total emission 3.Safety 4.Economic aspects There are several candidates: 1.HFC32 : Intermediate GWP and efficient 2.Propane(R290): Natural and efficiency but highly flammable 3.CO2: Natural but poor in efficiency 4.HFC410A: High GWP but applications are widely commercialized In comprehensive points of view, R32 is recommended as best alternative to new split air conditioners. R22 ALTERNATIVES