Preface. When fossil fuels are gone, there aren’t many ways to balance the unreliable, intermittent, and often absent for weeks at a time power from wind and solar.  Biofuels and burning biomass is one solution, it’s dispatchable and can kick in at any time to make up for lack of wind and solar, but there is far too little of it for power generation, let alone transportation fuels, soil nutrition and  replacing the high heat of coal to make cement, iron, steel, and other blast furnace / kiln products.  

So Plan B for renewable power would have to be hydropower.  That was the main proposal Stanford professor Mark Jacobson had to keep the electric grid stable and up and running.  But in 2017, a group of scientists pointed out that Jacobson’s proposal rested upon the assumption that we can increase the amount of power from U.S. hydroelectric dams 10-fold when, according to the Department of Energy and all major studies, the real potential is just 1% percent of that.  And since dams are so ecologically destructive, there would be a great deal of opposition to even building 1% of the dams Jacobson proposed.

How did they come up with just 1%? The National Hydropower Asset Assessment Program at Oak Ridge National Laboratory (ORNL) studied the potential for US hydroelectric power by looking both the 50,000 existing non-powered dams and new stream development. The dams that don’t generate power were assessed for their potential for electricity generation based on head-heights, average annual flow, seasonal weather patterns and run-off, and excluded dams that were too low and streams with minimal flow. ORNL estimated that the US could build another 5.6 GW of hydropower on existing non-powered dams, generating 32 TWh of electricity annually, which is just 1% of the total US electricity generation in 2015 (4,071 TWh).

For new dams, ORNL excluded national parks, scenic rivers and wilderness areas; rivers with insufficient water flow; and areas with project incompatibility issues, environmental concerns or existing hydropower facilities. They looked at over 3 million streams. Their results: 61 GW of new potential hydropower, capable of generating 315 TWh of electricity annually, but realistically at best a third of this due to the tremendous pressure against new dams in most areas from the harm they’d cause.

Plus, most states don’t have hydropower. Ten states have 80% of hydropower, with Washington state a whopping 25% of all hydro-electricity  generated (Homeland Security 2011).

Hydropower isn’t renewable, dams have a lifespan of 50 to 200 years.  The dams that exist are falling apart.  The American society of Civil engineers gives them a report card rating of D: “The average age of the 90,580 dams in America is 56 years. As our population grows and development continues, the overall number of high-hazard potential dams is increasing, with the number climbing to nearly 15,500 in 2016. Due to the lack of investment, the number of deficient high-hazard potential dams has also climbed to an estimated 2,170 or more (ASCE 2017).

More than half of California’s 1200 dams are rated high or extremely high hazard, yet only a few have submitted  inundation maps and emergency plans if they fail (Fimrite 2020).

Hydropower isn’t always available due to drought or held back for agriculture, drinking water, ecosystems, and fisheries. 

Without all that additional hydroelectricity, the 100% renewables proposal falls apart. There is no Plan C because of all the shortcomings of battery technologies.

Alice Friedemann  www.energyskeptic.com  Author of Life After Fossil Fuels: A Reality Check on Alternative Energy; When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Women in ecology  Podcasts: WGBH, Jore, Planet: Critical, Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, Kunstler 253 &278, Peak Prosperity,  Index of best energyskeptic posts

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1. Ultimately dams silt up, usually within 25 to 200 years, so hydro-power is not a renewable source of power.
2. Eventually the rebar in dams will rust and break apart the cement, causing the dam to fail (A Century from Now Concrete Will be Nothing But Rubble)
3. We’ve already dammed up the best rivers. There are now more than 45,000 dams around the world, affecting more than half — 172 out of 292 — of the globe’s large river systems.  The largest are 1,000 feet high.
4. Damming prevents salmon and other fish migration.
5. Rivers don’t just carry water downstream, they also carry sediment, such as silt, sand and gravel.  These sediments are critical for maintaining river deltas, home to more than 500 million people and some of the most productive croplands on the planet.  Dams trap sediment behind them, depriving deltas of what they need to be replenished, particularly in the face of rising sea levels.  Many deltas around the world—including those of the Mississippi, Nile and Mekong rivers—are sinking and shrinking in large part because the sediment they need is trapped behind upstream dams.
6. We’ve built dams in more than half of the large river systems and have decreased the amount of sediment flowing to the world’s coasts by nearly 20%. This is causing long-term harm to the world’s river ecosystems and raising risks that many coastal areas — sometimes hundreds of miles from the dams — will be flooded soon because they are deprived of sediments that help offset soil erosion. The harmful effects of ebbing soil deposits will be accelerated by the rising sea levels caused by global warming, say the researchers. More than 37% of the world’s population, or over 2.1 billion people, live within 93 miles of a coast.
7. Dams reduce biodiversity
8. Dams create habitats more easily invaded by invasive plants, fish, snails, insects, and animals
9. The water backed up behind a dam can inundate crops and towns, requiring people to be relocated.
10. Dams can increase greenhouse gases as impounded water gets choked with rotting vegetation
11. Dams, interbasin transfers, and water withdrawals for irrigation have fragmented 60% of the world’s rivers
12. Run-of-river dams can have a very negative impact and actually dam up the river or lake despite a name that implies otherwise (Opperman 2019).
13. It can take years to build even a small run-of-river project.  Below are the permits/agencies AMP needed to build 4 run-of-river turbines in the Ohio River:

LIST OF PERMITS/APPROVAL/LICENSES/EVALUATIONS

1. OPSB Certificate, Ohio Power Siting, Certificates for 50MW+ projects and T-line
2. Preliminary Permit, FERC, Permit to prepare and submit a License App.
3. License, FERC, Comprehensive energy project license
4. NEPA, EPA, Compliance with statute on federal projects
5. Section 404/10, Army Corps, Impacts to jurisdictional water
6. Section 408, Army Corps, Permission to impair federal structure
7. Section 401, OEPA, Impacts to wetlands/streams
8. Water withdrawal registration, ODNR, Withdrawal of water
9. NPDES, EPA/OEPA, Discharge of industrial water
10. Stormwater Permit, OEPA, Manage site/construction stormwater
11. Historic Preservervation Act, SHPO, Evaluation of cultural/historic resources
12. Endangered Species Evaluation, ODNR/USF&W, Evaluation of endangered/threatened species
13. License, FAA, Transmission Tower approval for aviation
14. ODOT Permit, ODOT, Roadway considerations/crossings
15. Flood Impact Approval, FEMA, To insure no impacts to flood waters

OTHER REQUIRED/POTENTIAL CONSULTING AGENCIES

1. U.S Dept. of Agriculture-Forestry
2. National Park Service
3. U.S. Bureau of Land Management
4. Federal Emergency Management Agency
5. U.S. Geological Services
6. U.S. Department of Commerce

OTHER REQUIREMENT Regional Transmission Organization Interconnection Process (more than 20 MW)–PJM or MISO in our region

References

ASCE. 2017. Infrastructure report card: Dams. D. American society of civil engineers.

Fimrite, P. 2020.  Even after Oroville near-disaster, California dams remain potentially hazardous. San Francisco Chronicle.

Goldsmith, E., et al. 1984.  The Social and Environmental Effects of Large Dams. Sierra Club Books

Homeland Security. 2011. Dams and energy sectors interdependency study. U.S. Department of Energy and Homeland Security.

McCully, P. 2001. Silenced Rivers: The Ecology and Politics of Large Dams. Zed Books.

Opperman, J. 2019. Crocodiles are not geckos: the realities of Run-of-river hydropower. Forbes.

Orego, J. P. 2012.  River Killers: The False solution of Mega-dams. from “The Energy Reader: Overdevelopment and the Delusion of Endless Growth” by Tom Butler, eds et al.

Pearce, F. 1992. The Dammed: Rivers, Dams, and the Coming World Water Crisis.  Bodley Head.

Poff, L. et al. April 3, 2007. “Homogenization of Regional River Dynamics by Dams and Global Biodiversity Implications,” Proceedings of the National Academy of Sciences 104: 5732–5737.

International Energy Agency, Key World Energy Statistics (Paris: World Commission on Dams. 2000. Dams and Development: A New Framework for Decision-Making. Earthscan.