January 20, 2016

Stream Heat Model Strengthens Water-Energy-Land Dialogue

PNNL researchers developed new way to understand stream temperatures

The new model can simulate stream temperature to explicitly account for the impacts of climate change and human activities, such as using freshwater for power plant steam generation and cooling. The ability to simulate stream temperature over complex river systems is important to support decisions on management and policy related to the water-energy-land nexus.

In the United States, 90 percent of electrical power comes from generating electricity using heat-conversion (thermoelectric) systems, fueled by coal, gas, oil, and nuclear generators. These power plants require fresh water to generate steam and for cooling purposes.

To better understand how stream temperature is influenced by climate change and human activities, scientists at PNNL developed a new modeling tool.

First they applied the new module in a river transport model and coupling it with a generic water management model within an Earth system model framework. From that, they were able to closely mimic the observed stream temperature variations from over 320 river gauges across the contiguous United States.

Their additional analysis focused on reservoir operations. They found that by altering the timing of streamflow to boost throughput in the low-flow summer season—from August to October—downstream temperatures could cool by as much as 1 to ~2°C.

"Our new capability lays a solid foundation for future studies on the water-energy-land nexus," said Dr. Hong-Yi Li, a PNNL hydrologist who led the study. "It opens exciting opportunities to evaluate our options for managing resources in an evolving environment."

For more information, read the research highlight.


About PNNL

Pacific Northwest National Laboratory draws on its distinguishing strengths in chemistry, Earth sciences, biology and data science to advance scientific knowledge and address challenges in sustainable energy and national security. Founded in 1965, PNNL is operated by Battelle for the Department of Energy’s Office of Science, which is the single largest supporter of basic research in the physical sciences in the United States. DOE’s Office of Science is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science. For more information on PNNL, visit PNNL's News Center. Follow us on Twitter, Facebook, LinkedIn and Instagram.

Published: January 20, 2016