IPCC Fourth Assessment Report: Climate Change 2007
Climate Change 2007: Working Group III: Mitigation of Climate Change

7.4.8 Other industries

This section covers a selection of other industries with significant emissions of high GWP gases. While some analyses include all emissions of these gases in the industrial sector, this chapter will consider only those which actually occur in the industrial sector. Thus, HFC and PFC emissions from use of automotive and residential air conditioning are covered in Chapter 5, section 5.2.1 and Chapter 6, section 6.8.4 respectively.

The manufacture of semiconductors, liquid crystal display and photovoltaic cells can result in the emissions of PFCs, SF6, NF3 and HFC-23 (IPCC, 2006). The technology available to reduce these emissions from semiconductor manufacturing, and the World Semiconductor Council (WSC) commitment to reduce PFC emissions by at least 10% by 2010 from 1995-levels are discussed in the TAR (IPCC, 2001a). US EPA (2006a) reports that emission levels from semiconductor manufacture were about 30 MtCO2-eq (7 MtC-eq) in 2000, and that significant growth in emissions will occur unless the WSC commitment is implemented globally and strengthened after 2010. US EPA (2006a) estimates that this 10% reduction could occur cost-effectively through replacement of C2F6 by C3F8 (which has a lower GWP), NF3 remote cleaning of the chemical vapour deposition chamber, or capturing and recycling of SF6. Emissions from the production of liquid crystal displays and photovoltaic cells, mainly located in Asia, Europe and the USA, are growing rapidly and mitigation options need further research.

SF6 emissions in 2000 from the production of medium and high voltage electrical transmission and distribution equipment were estimated at about 10 MtCO2-eq (2.8 MtC-eq) (IEA GHG, 2001). These emissions, mainly located in Europe and Japan, are estimated to have declined, despite a 60% growth in production between 1995 and 2003, mainly due to targeted training of staff and improved gas handling and test procedures at production sites. Emissions of SF6 at the end-of-life of electrical equipment are growing in relevance, and US EPA (2006b) estimates total SF6 emissions from production, use and disposal of electrical equipment at 27 MtCO2 in 2000 growing to 66 MtCO2 in 2020, if no mitigation actions are taken. Emissions from disposal of electrical equipment could be reduced by implementation of a comprehensive recovery system, addressing all entities involved in handling and dismantling this equipment (Wartmann and Harnisch, 2005).

A third group of industries that emits hydrofluorocarbons (HFCs) includes those manufacturing rigid foams, refrigeration and air conditioning equipment and aerosol cans, as well as industries using fluorinated compounds as solvents or for cleaning purposes. This group of industries previously used ozone-depleting substances (ODS), which are subject to declining production and use quotas defined under the Montreal Protocol. As part of the phase out of ODS, many of them have switched to HFCs as replacements, or intend to do so in the future. Mitigation options include improved containment, training of staff, improved recycling at the end-of-life, the use of very low GWP alternatives, and the application of not-in-kind technologies. A detailed discussion of use patterns, emission projections and mitigation options for these applications can be found in IEA GHG (2001), IPCC/TEAP (2005) and more recent US EPA reports (2006a,b).

IEA GHG (2001) estimated that global fugitive emissions from the production of HFCs will rise from 2 MtCO2-eq (0.6 MtC-eq) in 1996 to 8 MtCO2-eq (2.2 MtC-eq) by 2010. Solvent and cleaning uses of HFCs and PFCs are commonly emissive despite containment and recycling measures. IEA GHG (2001) forecast that these emissions would increase to up to 20 MtCO2-eq/yr (5.5 MtC-eq/yr) by 2020. However other analyses suggest a more moderate growth in emissions from solvent applications to about 5 MtCO2-eq/yr (1.4 MtC-eq/yr) by 2020 (IPCC/TEAP, 2005).