The Oak Ridge National Laboratory analysis concluded that currently undeveloped streams could support roughly 65 gigawatts of new hydropower. Streams on lands currently under federal protection could host an additional 19 gigawatts, the report said.
Energy Secretary Ernest Moniz, speaking at a Washington conference hosted by the National Hydropower Association, said that amounted to more than double current production levels.
It's time to "pull the cover off this hidden renewable right in front of our eyes," Moniz said.
The push comes after President Obama signed into law last year a measure to spur development of small hydropower projects and revive non-producing dams. The National Hydropower Association estimates the law could spark 60 gigawatts of new hydropower by 2025.
Much of the hydropower potential identified in the report comes from the Pacific Northwest. Washington, Idaho and Oregon had the top, second- and fourth-most undeveloped capacity at 6.1, 4.9 and 4.5 gigawatts, respectively. Alaska clocked in at third, posing an opportunity to support slightly more than 4.5 gigawatts of hydropower.
Some other regions could host significant amounts of new hydropower, the report noted. Kansas has a potential for 2.5 gigawatts; Nebraska could support 1.9 gigawatts; Missouri has 2.5 gigawatts of untapped capacity; Pennsylvania is looking at possibly 2.4 gigawatts.
Still, Moniz said the Department of Energy and the industry will have to monitor how a changing climate affects hydropower viability.
Moniz said drought that some scientists have linked to climate change has posed risks to hydropower production. He noted that the Energy Department is undergoing a second round of assessments as to how climate change affects water resources.
Hydropower generation hit a 10-year high in 2011, hitting 319,355 megawatt-hours according to the U.S. Energy Information Administration. But then drought set in — generation plummeted 15.7 percent between then and last year, when hydropower provided 269,136 megawatt-hours of power.
Moniz said climate change has hurt hydropower for several years. He noted the Energy Department-run Bonneville Power Administration failed to meet its electricity obligations in 2010 because drought reduced the Columbia River's water levels.
"The problem hasn't gone away," he said. "These uncertainties affect long-term capital planning horizons, which again could threaten our goal of doubling."