Sangwon Suh
University of California, Santa Barbara
Sangwon Suh is a professor at the Bren School of Environmental Science and Management at the University of California, Santa Barbara.
The Paris Agreement of 2015 adopted the ambitious target of capping global greenhouse gas (GHG) emissions to limit the global mean temperature increase to less than 2°C. Meeting this target will require an aggressive and unprecedented effort to decarbonize global electricity generation while deploying a variety of energy-efficient and demand-side technologies to reduce fossil energy consumption. Because reaching this 2°C target will require a transformation of global energy systems and infrastructure, a careful assessment of the environmental impacts and resource requirements of these technologies is needed. Furthermore, many of the necessary demand- and supply-side technologies are rapidly changing in their capabilities, costs and environmental impacts, highlighting the importance of accounting long-term technological changes and regional differences their assessment.
To understand the environmental benefits, risks and tradeoffs of GHG mitigation technologies the United Nations Environment Programme’s International Resource Panel (IRP) commissioned a series of reports. The first report, Green Energy Choices (Hertwich et al. 2015), assessed the environmental and natural resource impacts of low-carbon electricity supply technologies by 2050. This analysis builds on that of the previous IRP report by integrating both supply- and demand-side mitigation technologies in a single model to understand their aggregate environmental and resource impacts when deployed together at the global scale. This analysis represents the first comprehensive global assessment of the life-cycle environmental and resource implications low-carbon supply- and demand-side technologies under a 2°C scenario, and it includes over 60 technologies in total.
We constructed a scenario-based, integrated hybrid life cycle assessment (LCA) model to evaluate the environmental benefits and impacts of demand-side technologies from 2010 to 2050 under electricity scenarios consistent with the International Energy Agency’s 2°C mitigation and 6°C business-as-usual scenarios. Specifically, we examine the impacts of over 30 demand-side technologies in 9 global regions from 2010-2050 in the following clusters: efficient lighting (including LEDs), building insulation, demand-side energy management, information and communication technology (ICT), efficient copper production, industrial co-generation, passenger transport (including electric vehicles), and freight transportation.
LCA results confirm that demand-side technologies exhibit substantial environmental co-benefits in most impact categories. Energy-efficiency improvements to buildings and industry, and increased vehicle fuel efficiency offer the greatest near-term environmental benefits. For example, present-day efficient lighting can reduce impacts by 20-85% while building shell and demand-side energy management technologies can reduce GHG emissions by 20-60%. Some technologies, for example replacing gasoline vehicles with battery electric vehicles (BEVs), require greater quantities of metals. The benefits of demand-side technologies generally increase as technologies improve and electricity is decarbonized, with the exception of industrial co-generation. Results also highlight that electrification of transportation should be preceded by electricity decarbonization, especially in regions like China and India that have more GHG-intensive electricity mixes.
Scenario analysis confirms the overall benefits of aggressive deployment of energy-efficient and demand-side technologies when combined with electricity decarbonization. While a transition to BEVs for passenger transportation may contribute to increased human toxicity impacts, the 2°C scenario shows lower impacts in human toxicity and other environmental impacts overall, with the exception of metal consumption.
• Life cycle sustainability assessment , • Sustainable energy systems , • Advances in methods (e.g., life cycle assessment, social impact assessment, resilience a
