Making traditional hydropower more environmentally friendly
On September 7, the University of Minnesota was awarded a $250,000 grant from the U.S. Department of Energy (DOE) to develop state-of-the-art computational tools that will advance the use of aerating turbines at hydropower facilities.
The project is a collaborative effort between the University of Minnesota’s St. Anthony Falls Laboratory (SAFL) and Alstom, a global leader in energy technology development and U.S. power generation. In addition to the DOE funds, Alstom will provide $250,000 in matching funding.
The grant is part of a total of nearly $17 million awarded by the DOE and the Department of the Interior over the next three years to advance hydropower technology. Sixteen projects in 11 states were selected for their potential to develop innovative technologies that increase the nation’s ability to generate renewable, environmentally responsible, and cost-effective electricity from water resources. The funding will help advance the administration’s goal of meeting 80 percent of our electricity needs from clean energy sources by 2035.
The SAFL project is aimed at developing a conventional hydropower turbine aeration test bed integrating cutting-edge laboratory experiments and computer simulation tools to help advance hydropower development. Through this research, SAFL and Alstom will address an important issue plaguing the conventional hydropower industry: the need to improve both the efficiency of hydropower facilities and their environmental impact.
“Hydropower turbines often have to shut down – especially in the summer, when the power is needed most – because they pull water from the bottom of the reservoir where it’s not oxygenated,” explains SAFL researcher John Gulliver, Professor of Civil Engineering. “Releasing that non-oxygenated, colder water can suffocate the river downstream.”
Turbine aeration is one of the most cost-effective ways to address this problem. “The idea is to release bubbles along the hydroturbine blade, and the bubbles have a lot of mass transfer. You want oxygen to transfer from the bubble into the water.”
Through their work, Gulliver and the other principal investigators at SAFL, Civil Engineering professor and SAFL director Fotis Sotiropoulos and Civil Engineering professor emeritus Roger Arndt and their research teams will develop a modeling tool to advance the development and implementation of aerating turbines at hydropower facilities to improve water quality. The two-year project will combine a physical test bed with new analytical models for investigating how the shape and operation of hydropower turbine blades affects oxygen transfer and aeration.
“We’re excited to be working with Alstom on this,” said Gulliver. “They came to SAFL because they recognized that we had the unique ability to do all three parts of the project together in one place – the detailed experiments in the SAFL water tunnel, the fluid mechanics experiments measuring oxygen transfer, and the computational modeling.”
In addition to the DOE and Alstom funds, The University of Minnesota is contributing $63,000 as matching funds, half of it made possible by the Institute on the Environment’s Initiative for Renewable Energy and the Environment (IREE) and the other half from the College of Science and Engineering and SAFL.
In summing up the project’s long-term effect, Gulliver said “It’s all about reducing the environmental impact of hydropower facilities on the river, so they can produce more energy and have a river that is functional and cleaner.”