Non-powered dams across US promise huge energy potential

Hydropower already accounts for about one-third of all the clean energy generated in the US, but it could produce even more without the need to build even a single new dam.

That’s because there are so many non-powered dams — that is, dams that weren’t built to generate electricity — across the country. In fact, dams not used for hydropower far outnumber the power-purposed ones: the US Department of Energy (DOE) estimates there are more than 80,000 of the former, compared to around 2,500 of the latter.

“The abundance, cost, and environmental favorability of NPDs (non-powered dams), combined with the reliability and predictability of hydropower, make these dams a highly attractive source for expanding the nation’s renewable energy supply,” notes the DOE in a new study examining the potential for greater hydropower across the US.

Existing conventional powered dams current produce around 78 gigawatts (GW) of electricity nationwide, while pumped-storage dams add another 22 gigawatts of capacity. Developing the full potential of today’s non-powered dams could add more than 12 GW of additional generating capacity, according to the DOE.

The department conducted the study as part of the Obama Administration’s “all-of-the-above” energy strategy, which aims to maximize domestic energy production from all fuel sources, fossil or not.

The greatest potential for additional hydropower from existing facilities was found at locks and dams along the Ohio, Mississippi, Alabama, and Arkansas rivers. The facilities are all owned by the US Army Corps of Engineers.  The top 10 sites alone have the potential to generate around 3 GW of energy, while the top 100 sites provide up to 8 GW of electricity. The DOE adds that “many of these dams could also likely be converted to power-generating facilities with minimal impact to critical species, habitats, parks or wilderness areas.”