PNNL

Abstract

Power system operations are sensitive to climate-driven variations in both energy demands and water availability. Yet the combined effect of these impacts on power system adequacy is rarely evaluated. Here we assess power shortfall risk for the U.S. Pacific Northwest under combined climate impacts on loads and hydropower generation. Climate change emerges as both a risk and an opportunity; potential shortfall events occur more readily, but are significantly less severe in nature (annual shortfall probability is more than doubled for a business as usual policy; average shortfall event duration is halved and average maximum shortfall is reduced by up to ~60%). A seasonal reversal in shortfall risk occurs: winter shortfalls are eradicated due to reduced building heating demands, whilst summer shortfalls multiply as increased peak loads for day-time cooling coincide with impaired hydropower generation. Many of these summer shortfalls go unregistered when climate change impacts on loads and hydro dispatch are analyzed in isolation—suggesting an important role of compound events.