Edie Zagona,
Research Professor, Department of Civil, Environmental and Architectural Engineering
Director, Center for Advanced Decision Support for Water and Environmental Systems (CADSWES)
University of Colorado at Boulder
zagona@colorado.edu
cadswes2.colorado.edu/~zagona

The Water Energy Nexus and CADSWES Hydropower Research  and Applications


The talk will begin with a brief introduction to the research center, CADSWES, the RiverWare modeling tools, 
and an overview of the water-energy nexus and the role of hydropower and water management in that context. 
The Department of Energy (DOE) has goals for doubling the 2010 level of renewable power generation by 2020. 
Additionally, a memorandum of understanding between DOE, the Bureau of Reclamation and the U.S. Army Corps 
of Engineers has set additional goals of increasing both the value and sustainability of hydropower in the 
U.S.  RiverWare's hydropower optimization algorithms provide a robust tool for scheduling hydropower 
operations with value objectives for two large utilities, Tennessee Valley Authority and Bonneville Power 
Administration, with distinct valuation metrics and complex operational constraints. To further increase 
renewables, utilities now are faced with the challenge of integrating wind power, which is highly variable. 
Past estimates of the flexibility of conventional hydropower for managing variability and uncertainty are in 
question due to conflicting constraints. In a study for Oak Ridge National Labs we quantified the 
limitations of wind penetration in a hydro dominated system. Spilling to avoid wind curtailment is also 
problematic in the introduction in the spillway of dissolved gases fatal  to endangered fish. Another study 
with ORNL develops a TDG model in RiverWare that allows utilities to manage that risk as well.  In a study 
with the National Renewal Energy Lab (NREL), we linked RiverWare model of the Middle Columbia to PLEXOS, the 
model of the US Western Interconnection used to project wind penetration levels across the western US. The 
results show the effect of detailed hydropower modeling on the power system and its benefits such as the 
decrease in overall production cost and reduction of variable generation curtailment. A few other CADSWES 
R&D projects may be briefly described if time allows.