The US Department of Energy (DOE) Water Power Program has assessed the National Inventory of Dams (NID) to evaluate the potential of additional hydropower from non-powered dams (NPDs) that could contribute to the amount of renewable energy available across the nation. Oak Ridge National Laboratory (ORNL), with input from the Idaho National Laboratory (INL), executed a technical analysis and identified 54,000 NPDs in this hydropower resource assessment effort. The main purpose was to estimate the maximum generation potentials of all NPDs in a nationally consistent manner (Figure 1). This information is available to developers for use in focusing their attention on selected regions for more detailed site identification and analysis. This resource assessment is not intended to provide economic feasibility of the 54,000 potential sites.

The findings indicated that there is the potential to add up to 12.1 GW (12,100 MW) at NPDs in the US. However, this estimate does not consider economic limitations on facility capacity—it does include assumptions that all of the water passing a facility can be converted to electrical energy and that hydraulic head is constant at facilities. Those economic considerations will be the focus of future investigations and reporting. Site-specific designs will (a) incorporate detailed monitoring of daily and hourly head and flow variations and (b) balance initial costs with energy revenue to yield site-specific designs of lesser capacity and production potential.

Most of this potential is located at US Army Corps of Engineers (USACE) lock and dam facilities on the Ohio, Mississippi, Alabama, and Arkansas rivers. The concentration of potential hydropower available at the top 100 existing NPDs is a substantial portion of the total. These facilities collectively exhibit a potential of up to 8 GW of clean, reliable hydropower. Many of these dams could likely be converted to power-generating facilities without impacting critical habitats, parks or wilderness areas. Among the top 100 candidates for hydropower development at identified NPDs, 81 are USACE projects.

The National Hydropower Association (NHA) estimated that these projects will bring enough new renewable energy to the region to serve more than 250,000 households and help avoid more than two million metric tons of carbon dioxide emissions each year. Recent developed and proposed project capacities provide insights into the distinction between the potential reported herein for undeveloped sites and the design capacity that comes to fruition after site-specific daily and hourly time series data and economics are considered. In the last decade, three of the USACE locks and dams on the Ohio River were developed: Cannelton (Cannelton, IN), Smithland (Livingston County, KY), and Meldahl (Braden County, KY), with installed capacity of 88MW, 76 MW and 111 MW, respectively. Two additional USACE dams on the Ohio River are also candidates for development by American Municipal Power (AMP), Willow Island (Pleasants County, WV) and RC Byrd (Gallipolis Ferry, WV), with proposed capacity of 44 MW and 48 MW, respectively. These Ohio River design capacity values are approximately one-third of the potential that would have been reported by the methodology documented herein. This ratio is likely to vary significantly across regions and river settings. Thus, the importance of site-specific daily and hourly flow and head analyses, in addition to other site-specific design factors, should not be overlooked in making detailed resource planning and investment decisions related to the development of NPDs.

Summary of Non-powered Dam Hydropower Potential by Federal Agency

Federal Agency NPDs located on land owned by agencies NPDs owned/operated by agencies
# of NPDs MW # of NPDs MW
US Army Corps of Engineers 121 517.1 373 8241.6
Bureau of Reclamation - - 191 268.3
Bureau of Land Management 657.0 102.4 6.0 0.3
Department of Defense 219.0 19.7 162.0 11.7
Forest Service 2,531.0 637.6 129.0 5.5
Fish and Wildlife Service 297.0 94.0 143.0 6.5
National Park Service 96.0 3.6 42.0 0.5
Bureau of Indian Affairs 694.0 56.2 90.0 8.1
Other * 4 0.1 34 70.2

*Other: Includes the International Boundary and Water Commission (IBWC), US Department of Energy (DOE), Tennessee Valley Authority (TVA), and US Geological Survey (USGS).