Is demand-side management environmentally beneficial? Analyzing the greenhouse gas emissions due to load shifting in electric power systems

Abstract

Demand-side management via load shifting allows synchronizing electricity demand with supply from fluctuating renewable energies. Synchronizing seems desirable so that electricity from renewables will not be curtailed and overall greenhouse gas (GHG) emissions can be reduced. However, the change in GHG emissions by utilizing load shifting in electric power systems depends on the prevailing electricity generation mix. Although some publications discuss the impact of load shifting on the GHG emissions of specific electric power systems, a systematic analysis on the GHG emissions due to load shifting in general is still missing. We fill this gap by determining the changes in GHG emissions that result from cost-optimal load shifting in electric power systems. For our analysis, we consider the impact of load shifting in electric power systems with different shares of low-, medium-, and high-emission technologies. The results show that GHG emissions can both increase and decrease by utilizing load shifting, depending on the electricity generation mix in electric power systems. Hence, we emphasize that load shifting is not per se environmentally beneficial. Furthermore, we analyze the electric power systems of three regions of the world and conclude that utilizing load shifting is not reducing GHG emissions in every region today. However, the targeted electricity generation mix for the regions in 2050 suggests that the utilization of load shifting will reduce GHG emissions in the future. Furthermore, we show that under a sufficiently high CO2-price, load shifting is always environmentally beneficial in today's electric power systems.