Operational Impacts of Drought and Changing Electricity Load on the Western U.S. Power System in Low and High Renewable Systems

Abstract:

How the power system in the Western U.S. responds to future drought and increasing temperatures depends on its composition. A largely thermal (coal, natural gas, and nuclear) power system will adapt differently than a high renewable penetration system. We explore the combined impacts of drought and climate-forced electricity load in the Western U.S. under a range of potential future electricity infrastructures. We use hourly production cost models to simulate power system operation and quantify the impacts of drought and changing electricity load on production costs and use of thermal generators. We explore these impacts on four potential infrastructures determined by least-cost optimization in capacity expansion models under a range of renewable energy capital costs and climate-forced water availability and temperature. Electricity load changes are spatially diverse according to regional warming and historical sensitivity to temperature. We explore moderate and high load cases selected from climate models. We explore three different water conditions and their associated impact on hydropower: a non-drought year and two different drought years. The operational results show how the response to drought and temperature forcings in the four infrastructures vary by type of generation used and generation cost impacts. This work links hydrology models, global circulation models, an electricity capacity expansion model, and an electricity production cost model to address these questions and suggests future work under near-zero emission renewable scenarios and in other regions. This talk will focus on production cost modeling (operational) results which provide particular insight into hourly operations.