As the grid evolves to incorporate more variable renewable energy sources, like solar power and wind energy, hydropower will play a key role in ensuring it remains reliable and stable. A major challenge for hydropower is how to meet growing energy demand while mitigating environmental impacts. But what if, rather than identifying ways to mitigate impacts, energy and environment priorities could both be optimized? Research from the HydroWIRES Initiative, led by the U.S. Department of Energy's (DOE's) Water Power Technologies Office (WPTO), investigates ways to plan water releases to support both energy and environment objectives, thus reducing the environmental impact of hydropower facilities and supporting power generation.
"There's a legacy paradigm in hydropower that pits power generation against environmental mitigation and protection measures, but it doesn't have to be like that. Our research shows that co-optimizing energy and environmental outcomes can lead to better outcomes in both areas," explained Brenda Pracheil, Pacific Northwest National Laboratory (PNNL) Earth scientist, fisheries biologist, and lead author of a report on co-optimization of hydropower outcomes.
Hydropower is an abundant, flexible energy source that provides nearly 30% of the country's utility-scale renewable energy, but hydropower facilities also affect the environment and natural resources. To that end, new HydroWIRES research from PNNL, Oak Ridge National Laboratory, National Renewable Energy Laboratory, Idaho National Laboratory, Argonne National Laboratory, and RTI International modeled operational approaches that optimize energy and environmental protection outcomes.
Focusing on Both Energy and Environment Priorities
Hydropower's ability to quickly increase or decrease power generation to meet changing electrical grid demand is tied to adjustable hydropower flows, or the amount of water flowing through a hydropower facility at any given time. More water released to flow through turbines means more power generated at a hydroelectric facility.
But power demand is only one factor that determines flows downstream of hydropower facilities. Minimum or other flow requirements are instituted during certain seasons, days, or hours to meet specific environmental priorities, such as supporting fish migrations through facilities or providing sufficient water to maintain fish spawning and growth habitats. These conditions are included in a hydropower facility's operational plan or license.
"We found that the environmental requirements for hydropower flows, such as minimum flows and restrictions on how quickly water flows can be increased and decreased over a given time, are most likely to limit operational flexibility during summer and the middle of the day, which in some cases is when the grid is most likely to experience stress," explained Vishvas Chalishazar, PNNL electrical engineer, grid resilience team lead, and co-author on the report. "But by co-optimizing energy and environmental outcomes, it's possible to create opportunities for energy-environment win-wins."
For more information
1000 Independence Ave. SW
Washington District of Columbia
États-Unis 20585
www.energy.gov
