Life cycle burden-shifting in energy systems designed to minimize greenhouse gas emissions: Novel analytical method and application to the United States

Energy systems are currently designed focusing only on minimizing their cost or, at most, including limits on greenhouse gas emissions. Unfortunately, electricity technologies performing well in global warming potential might not necessarily behave equally well across other sustainability criteria. Hence, policies focused solely on mitigating greenhouse gas emissions could potentially resolve one problem (i.e., climate change) by creating another, thereby leading to burden-shifting. Here, the occurrence and severity of burden-shifting in energy systems design are both investigated through the application of a novel approach integrating multi-objective optimization, life cycle assessment and multivariate regression based on elasticities. Environmental impacts are classified into three categories: no burden-shifting, total burden-shifting and partial burden-shifting, providing for the latter two a measure of their severity. Due to inherent trade-offs in the life cycle performance of technologies, discussed in detail in this work, the Paris Agreement 2 degrees C targets would lead to burden-shifting in the United States (total or partial) in up to eight environmental impacts. On the other hand, stringent carbon emissions reductions in line with the 1.5 degrees C targets can lead to burden-shifting in three environmental impacts. Indeed, in both cases undesirable increases in some damage categories of up to 1.64% for every percentage increase in cost can take place as a result of more stringent limits on greenhouse gas emissions compared to the least cost solution. Overall, this work aims to foster fruitful discussions on how to generate energy within the Earth's ecological capacity by expanding the analysis beyond climate change. (C) 2019 Elsevier Ltd. All rights reserved.