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

11.3 Overall mitigation potential and costs, including portfolio analysis and cross-sectoral modelling

This section synthesizes and aggregates the estimates from chapters 4 to 10 and reviews the literature investigating cross-sectoral effects. The aim is to identify current knowledge about the integrated mitigation potential and/or costs covering more than two sectors. There are many specific policies for reducing GHG emissions (see Chapter 13). Non-climate policies may also yield substantial GHG reductions as co-benefits (see Section 11.8 and Chapter 12). All these policies have direct sectoral effects. They also have indirect cross-sectoral effects, which are covered in this section and which diffuse across countries. For example, domestic policies promoting a new technology to reduce the energy use of domestic lighting lead to reductions in emissions of GHG from electricity generation. They may also result in more exports of the new technology and, potentially, additional energy savings in other countries. This section also looks at studies relating to a portfolio analysis of mitigation options.

11.3.1 Integrated summary of sectoral emission potentials

Chapters 4 to 10 assessed the economic potential of GHG mitigation at a sectoral scale for the time frame out to 2030 (for a discussion of the different definitions of potential, see Chapter 2). These bottom-up estimates are derived using a variety of literature sources and various methodologies, as discussed in the underlying chapters. This section derives ranges of aggregate economic potentials for GHG mitigation over different costs (i.e. carbon prices) at year-2000 prices.