Grid Integration: Hydropower's Role in the Next-Generation Grid

NREL's hydropower researchers perform cutting-edge research in multiple aspects of grid integration research, including hydropower's role in grid planning, operations modeling, reliability and resilience research, and how hydropower connects to other sectors.

NREL is the only national laboratory able to perform interconnectionwide grid operations modeling and analysis at nodal resolution and dispatch timescales—an important capability for understanding the full value of both hydropower and pumped storage hydropower. This expertise is leveraged from our previous successes with wind and solar integration research and applied to the hydropower industry.

Photo of wind turbines on a hill above a hydropower dam.

NREL's grid planning researchers improve hydropower's representation and its ability to provide high-capacity, extended-duration storage in capacity expansion models—a capability that is increasingly important as renewable penetrations increase.

We utilize two models:

Regional Energy Deployment System (ReEDS): NREL's flagship capacity planning model for the North American electricity system.

Resource Planning Model (RPM): NREL's capacity expansion model designed for a regional power system.

The ReEDS model helps stakeholders to understand hydropower's contributions from a national perspective, and RPM informs decisions at the utility service territory, state, or balancing authority level.


Stuart Cohen

Researcher V, Model Engineering

Like our work in capacity expansion planning, NREL works to improve hydropower's representation in grid operations modeling.

Framework for Linked Analysis of Streamflow and Hydropower

With support from the U.S. Department of Energy (DOE) Water Power Technologies Office, NREL researchers are developing the Framework for Linked Analysis of Streamflow and Hydropower (FLASH), a systems-engineering-based approach that will improve hydropower's representation in grid operations modeling.

FLASH combines NREL's grid integration expertise with the river-basin-scale modeling and water forecasting expertise of RTI International, a North Carolina-based nonprofit research organization and partner on this project. 

North American Renewable Integration Study

NREL's research in this area spans multiple scales, from the North American Renewable Integration Study (NARIS) that looks at hydro's ability to enable ever-increasing amounts of clean energy to investigating how small, cascading hydro can be operated so that plants meet revenue objectives without significantly impacting a river's natural flows.

NARIS' hydropower research helps the water power industry understand the value of hydropower and pumped storage hydropower to an evolving, North American grid. The study will identify aspects of flexibility that will be valuable in the future grid so new technologies can be tailored to provide enhanced grid value.

Additional Research Projects

NREL researches the value of new pumped storage hydropower technologies and projects from the perspective of the developer, owner, and operator—helping each better understand the worth of their investments.

For our ternary project, we worked with the developer, Absaroka Energy, and its equipment provider, General Electric Renewable Energy, to investigate the value of ternary pumped storage to the Pacific Northwest and California markets.

In our Obermeyer Hydro project, we supported Obermeyer in its efforts to design and site an easy-to-install turbine that is expected to markedly reduce civil works costs.

We also worked closely with Natel Energy to develop a control strategy for operating a series of small, low-impact, cascading hydro plants so the plants would meet revenue objectives without significantly impacting a river's natural flows—addressing a critical environmental concern and providing the possibility of using small-scale hydropower for stream restoration.

Additionally, NREL is developing the next generation of grid operation simulation software. This research, which is part of DOE's Water Power Technology Office's HydroWIRES initiative and NREL's Scalable Integrated Infrastructure Planning (SIIP) Project, will:

  • Integrate river-basin and reservoir operations water models into the SIIP grid operations framework
  • Improve hydropower's representation in grid operations models
  • Allow the near-term and seasonal value of water to be included in grid dispatch decisions.

We are leveraging techniques learned in our integrated energy system and ReEDS capacity expansion work to benefit hydropower.


Stuart Cohen

Researcher V, Model Engineering

The NREL hydropower team works in several areas of reliability and resilience research.

For both the ternary and Obermeyer projects, we evaluated how the addition of the pumped storage hydropower projects would improve the resilience of the grid, and we developed a new dynamic presentation of the ternary unit so that the full capabilities of the technology are well-represented in the transient analysis.

Leading DOE's Extreme Events research, NREL also investigates hydropower's role in providing grid power during times of extreme weather events.

NREL is also a key member of the Office of Electricity's North American Energy Resilience Model project, helping to ensure abundant, reliable, and affordable energy.


Tessa Greco

Water Power Special Projects Lead

NREL researchers are investigating the environmental impacts of hydropower, working to optimize its integration into a low-carbon electricity grid while mitigating negative environmental impacts.

Renewable Energy Focus Study

NREL partnered with Oak Ridge National Laboratory and Pacific Northwest National Laboratory to use a production cost model to understand the role of hydropower in a U.S. power grid with increasing levels of renewable energy. Results, published in December 2022 in the Renewable Energy Focus article Hydropower Operation in Future Power Grid With Various Renewable Power Integration, point to future hydropower costs and use relying on water availability, which needs to be accurately understood to inform system operations.

Water Biology and Security Study

In a study, NREL collaborated with Oak Ridge National Laboratory to analyze how shifts in hydropower operations affect hydropower plants’ effects on aquatic environments. Using power cost modeling, researchers characterized how current and future seasonal patterns could impact hydropower’s contribution to the grid as well as local environments. Results, published August 2022 in Water Biology and Security under the title Shifts in Hydropower Operation To Balance Wind and Solar Will Modify Effects on Aquatic Biota, note that the shift away from fossils fuels will increase the demand for flexible hydropower to stabilize wind and solar energy in the grid. Aquatic environments might be affected by changes in water flow to meet this rising demand, but mitigation options in this study point the industry toward potential solutions. 


Thushara De Silva

Researcher III, Model Engineering