The role of international drivers on UK scenarios of a low-carbon society

An integrated set of low-carbon society (LCS) scenarios for the UK were analysed using the UK MARKAL Macro (M-M) model. A $100/tCO(2) carbon price scenario was compared with long-term LCS scenarios with a domestic 80% CO2 reduction target. As M-M is a national-level model, a set of five international drivers were investigated, and grouped under Annex I consensus and Global consensus assumption sets. For economy-wide results the inclusion of international aviation and potential large-scale purchases of CO2 permits (when available) are most important. For sectoral implications, all international drivers considered here are important; for example in divergent overall size and configuration of the UK electricity sector. The carbon price scenario and set of 80% LCS targets scenarios give GDP losses rising from 0.36% to a range of 1.64-2.21% in 2050. This steep cost convexity in deep CO2 reductions represents increasing efforts to decarbonize the UK energy system, and the further impact of key international drivers. This illustrative analysis demonstrates that UK policy makers should be cognisant of, and flexible with respect to, international strategies on LCS and emission reduction targets.