Sustainable Re-Design of Hydropower Systems for Renewable Energy Transitions and Climate Change Adaptation

In the context of accelerating climate change and a rapidly evolving energy sector, managing hydropower systems requires balancing competing socioeconomic and ecological goals. This dissertation presents three studies that collectively illustrate a comprehensive approach to adapting hydropower operations in support of renewable energy transitions and increased climate resilience. At the heart of this work is the challenge of managing multi-purpose reservoirs that provide energy, water supply, and ecosystem support. The first study addresses a gap in the literature with respect to integrating water-energy-economic models that can explore tradeoffs in operating hydropower systems for conflicting objectives across these sectors. Such a model is introduced and coupled with a multi-objective optimization algorithm to identify alternative reservoir operation strategies that dominate historical operations in the Columbia River Basin across all identified objectives. The second study investigates how robust these operations are to potential climate and energy futures in which the grid decarbonizes at different rates in concert with the climate changing to varying degrees. Two forms of sensitivity analysis are then used to generate valuable insights about how to design robust operations. Finally, the third study uses these insights to re-optimize operating rules that condition reservoir release decisions on variables to which even robust operations are sensitive. This allows seasonal hydropower operations to adapt in response to changing resource availability, such as shifts in snowmelt timing and solar energy production. Together, these studies offer both methodological and practical contributions to the literature on hydropower operations, enhancing our understanding of how large river systems like the Columbia should adapt to the dual pressures of climate non-stationarity and grid decarbonization.