The TIAM-UCL Global Energy Systems Model: Critical Comparison of UK and Global Climate Decarbonisation Trajectories

Mr William Usher, Energy Institute, University College London

Given the limited progress achieved at COP 15 in Copenhagen, UK based policy makers and international negotiators have a need to understand the economic, environmental and technological implications of meeting CO2 emission reductions at least cost under differential levels of domestic and international policy ambition.  However, there is currently a large difference between the stated ambition in carbon reduction levels of the UK and other countries. The UK has set an ambitious long-term mitigation target of 80% CO2 reduction over 1990 levels by 2050. This can be achieved  solely through domestic reduction or in conjunction with purchasing emissions credits on the international market.  The carbon price on the international market is heavily influenced by regional and country-specific climate policy ambition. Whereas the UK has committed to a legally binding CO2 emissions target, major economic powers, such as the USA and China, have committed only to modest reductions in the carbon intensity of GDP.

This paper analyses the economics of domestic CO2 reductions to meet UK’s long-term target under four global scenarios that characterise plausible future global levels of policy ambition.  These include a base case, GDP intensity improvements, an absolute CO2 reduction target for OECD members and a global absolute CO2 target reduction.  For each of these, the UK either substantially leads or at least matches the international targets.

The scenarios are analysed via the TIAM-UCL model, a newly developed 16 region global energy systems model, with a specific UK region. TIAM-UCL is a technologically explicit partial equilibrium energy economic model incorporating characterisation of global trade links. It is designed to investigate the range of global drivers that will affect long-term energy systems development in the UK.