A Grey-System Assessment of Energy Use, CO 2 Emissions and Sectoral Environmental Damage in South Africa’s Electricity Sector

Abstract

South Africa’s reliance on coal-fired generation continues to dominate both its energy balance and its emissions inventory. Despite a sustained body of work on the country’s electricity sector, comparatively little attention has been paid to grey-system techniques, which are useful when one wishes to rank heterogeneous alternatives or to project trajectories from short, partially uncertain time series. This paper applies Grey Relational Analysis (GRA) and the GM (1, 1) Grey Prediction Model to a dataset assembled from previously published national energy and CO 2 statistics with a sectoral input-output life-cycle inventory for 1990 to 2012. GRA ranks twelve high-impact industrial sectors against four damage categories, namely human health, ecosystem quality, climate change and resources, with weights set to 0.30/0.20/0.30/0.20. The procedure isolates Electricity ( γ = 0.344) and Coal mining ( γ = 0.700) as the only two sectors whose damage profile departs sharply from the ideal low-burden reference; the remaining ten cluster above γ = 0.95. The GM (1, 1) model is then fitted to series for GDP, CO 2 emissions, total primary energy supply (TPES) and total final consumption (TFC). All four models satisfy grade I (good) or grade II (qualified) GM (1, 1) accuracy criteria, with mean absolute percentage errors below 4%. Medium-term baseline projections to 2030 indicate continued upward pressure on emissions in the absence of structural change: CO 2 emissions reach approximately 657 Mt, TPES approximately 224 Mtoe and TFC approximately 102 Mtoe. The projected 2030 CO 2 level sits at the upper end of South Africa’s Nationally Determined Contribution peak-plateau-decline band (398-614 Mt CO 2 -eq), suggesting that the pledged trajectory could be difficult to achieve under the assumptions of the GM (1, 1) baseline. These results corroborate the earlier finding that mitigation effort should be concentrated on Eskom’s generation fleet and the upstream coal value chain, and they quantify the extent to which mitigation must outpace the historical trend if the Just Energy Transition Investment Plan (JET-IP) closure schedule is to deliver the Nationally Determined Contribution (NDC) target.