LLNL partners with FATHOM to develop new additive manufacturing technology
ICCT: US domestic airlines show modest improvement in fuel efficiency since 2010, top performers Alaska and Spirit widen lead

ORNL assessment finds >65 GW of untapped hydropower in US rivers and streams

A new assessment conducted by Oak Ridge National Laboratory (ORNL) has identified more than 65 gigawatts of untapped hydropower potential in US rivers and streams. The greatest hydropower potential was found in western US states, including Alaska, California, Colorado, Idaho, Montana, Oregon and Washington. Kansas, Missouri, Pennsylvania and Wyoming led the rest of the country in new stream-reach hydropower potential.

The highest potential was identified in the Pacific Northwest Region (32%), followed by the Missouri Region (15%) and the California Region (9%). In total, the undeveloped NSD capacity is 84.7 GW, and the undeveloped NSD generation is estimated to be 460 TWh/year. When areas protected by federal legislation limiting the development of new hydropower (national parks, wild and scenic rivers, and wilderness areas) were excluded from the analysis, the estimated NSD capacity falls to 65.5 GW, slightly lower than the current existing U.S. conventional hydropower nameplate capacity (79.5 GW; NHAAP, 2013).

Undeveloped NSD generation with these areas excluded is estimated to be 347.3 TWh/year, roughly 128% of the average 2002–2011 net annual generation from existing plants (272 TWh/year; EIA, 2013). Since the assessment was designed to identify potential run-of-river projects, NSD stream-reaches have higher capacity factors (53%–71%), especially compared with conventional larger-storage peaking-operation projects that usually have capacity factors of around 30%.

—ORNL NSD assessment

Development potential by sub-basin. The New Stream-reach Development (NSD) Assessment analyzed more than 3 million stream-reaches, making it the most detailed evaluation of new US hydropower potential to date. Source: ORNL NSD. Click to enlarge.

The US Department of Energy (DOE) tasked ORNL with evaluating the new stream-reach development resource potential of more than 3 million US streams. Such a wide spatial scope required a methodology that can (1) resolve aggregate potential within hydrologic regions and electric power systems; and (2) enable the modeling of regional and national scenarios for existing and new electric power generation technology deployment through the development of curves for hydropower capacity cost versus supply.

ORNL designed a methodology containing three main components: (1) identification of stream-reaches with high energy density; (2) topographical analysis of promising stream-reaches to estimate the characteristics of potential inundations of reservoirs; and (3) environmental attribution to spatially join the energy potential of stream-reaches with information related to the natural ecological systems; social and cultural settings; and policies, management, and legal constraints.

Some of the environmental, technical and socioeconomic factors variables included:

  • Endangered species;
  • Federally protected lands;
  • Water use and water quality concerns;
  • Fishing and boating access.

In addition to voluminous new data and the methodology, the NSD assessment focuses specifically on undeveloped stream-reaches, unlike previous assessments that examined all types of streams without further breakdown (i.e., including river segments with existing hydropower plants or non-powered dams).

Hydropower makes up 7% of total US electricity generation and continues to be the US’ largest source of renewable electricity. Hydropower also provides reliable baseload power day and night, providing greater flexibility and diversity to the electric grid and allowing utilities to integrate intermittent renewable sources such as wind and solar power.

The NSD Assessment builds on a 2012 Energy Department assessment that found more than 12 GW of hydropower potential at the nation’s existing 80,000 non-powered dams. The results of the new resource assessment show that there are opportunities to develop new hydropower projects around the country, most of which would likely be smaller, run-of-river facilities that could utilize new low-impact designs and technologies.




Its amazing what gigantic impact on the real environment these supposedly 'ecological' alternatives have.
Building 65GW of nuclear would have impact on the environment which is trivial in comparison.


Who said that Hydro energy was all harnessed in USA?

This is equivalent to 65+ new Nuke power plants or 130+ old coal power plants.

Putting people to work with the construction of clean hydro plants and dismantling of 130+ old CPP could be a win-win solution for USA?


Davemart, I am with you.

Harvey, I get your point on value-added infrastructure spend, but the jobs generated in the construction of 65 APS1000 (or equivalent) would be equally beneficial, with far less impact to the natural features of the country. I'm all for preserving, refurbishing, and maximizing the generation from current hydropower installations in the US (go grab the 12GW available and wring power out of the rest). But tread very, very carefully in any further construction.


I agree with Davemart and Herman. The jobs created only last a few years anyway. You can create jobs with any form of construction -- solar, wind, nuclear, wave/tidal -- all producing clean energy for a long time to come.


And nothing personal HarveyD, but I have come to detest the argument that this approach or that will create jobs. That is usually a political lie to garner votes while supporting some donor's pet project.


Sorry to have to repeat it, but added infrastructures create jobs, more wealth, economic prosperity and new government revenues to reduce the National and States debts etc.

More clean 24/7 e-energy production is required if USA wants to build more clean intermittent e-energy production facilities such as Solar, Wind and to progressively phase out many of the oldest dirty CPPPs.

Hydro facilities with adequate water reservoirs can be over equipped to better deal with peak demands.


I don't like the idea of damming up streams either, but when the current real-world alternative is to pollute them with mercury from coal-burning power plants, it seems likely that dams with mitigation techniques like fish ladders are a more environmentally responsible choice.


The ecological aspect is better for NSD than you think.

Hydropower is based on head (height of water drop) and flow rates, not hydrostatic pressure, which is what the big holding capacity of traditional dams seem to imply. A look at the physics formula for kinetic energy will tell you this. A set of low head, low capacity dams, intermittently operating will provide seasonal capacity comparable to wind or solar. But they will also accomodate flood control, management of marshes and fish hatcheries, and erosion control (underwater cement structures and open turbines will really help).

I contemplate these matters as the Raritan and Delaware river systems are about to crest into the fifth 200 year flood in 15 years. A furtune has already been spent here by the Army Corps of Engineers with all the environmental review you can imagine. I see no reason why we can't exploit micro-hydropower in the process.


HarveyD, You added elements to your argument. I can agree with the benefits of infrastructure, reduced debt, and clean energy. I just have a visceral negative reaction to the jobs argument.

The comments to this entry are closed.