The implications of upstream emissions from the power sector

Abstract

Upstream environmental burdens arise from the need to expend energy resources in order to extract and deliver fuel to a power station or other users. They include the energy requirements for extraction, processing/refining, transport and fabrication, as well as methane leakages from coal mining activities – a major contribution – and natural gas pipelines. The upstream carbon dioxide emissions associated with various power generators and UK electricity transition pathways towards a ‘low carbon’ future have been evaluated on a ‘whole systems’ basis. Carbon dioxide capture facilities coupled to fossil-fuelled plants are shown, for example, to deliver only a 70% reduction in greenhouse gas emissions (including both upstream and operational emissions), in contrast to the normal presumption of a 90% saving. In addition, the present UK greenhouse gas trajectories associated with transition pathways to 2050 are found to differ significantly from those produced by the British government's Department of Energy and Climate Change and its independent Committee on Climate Change. These bodies do not currently account for upstream, ‘fugitive’ greenhouse gas emissions. Therefore, there will actually remain further emissions upstream that are unaccounted for, even if the current UK carbon dioxide equivalent reduction targets are apparently met.