The Future of New American Hydroelectric Projects, Large and Small: Towards More Efficient and Environmental Use of Hydro Resources and Hope for Faster and Better Permitting and Regulatory Assessments

The Future of New American Hydroelectric Projects Large and Small: Towards More Efficient and Environmental Use of Hydro Resources and Hope for Faster and Better Permitting and Regulatory Assessments

Although the potential for hydropower is ultimately limited both regionally and globally, there is still some room to expand, particularly with smaller projects that presumably would be less impactful. In Canada there is at least one large project looming, not without some controversy, as the three leaders of Canada, Mexico, and the U.S. recently announced joint clean electric power goals for North America.

2016 Assessment by the U.S. Department of Energy: Hydropower Vision

The DOE’s recent report Hydropower Vision, emphasizes optimizing the existing hydropower fleet, exploring growth, and ensuring sustainable development and water use management. Outfitting some existing dams on big rivers like the Ohio, Mississippi, and Missouri, and their major tributaries, with hydropower facilities is a part of that vision. The DOE estimates that “U.S. hydropower could grow from its current 101 GW to nearly 150 GW combined electricity generating and storage capacity by 2050.” In the DOE model about 13 GW of the 49 GW increase potential by 2050 would be additions of generating capacity both at facilities like dams (powering non-powered dams (NPDs)), upgrades of existing hydropower facilities, and a limited amount of new ones. 36 GW capacity would be for pumped storage. From 1950 through 2015 hydropower has cumulatively provided 10% of U.S. power and 85% of U.S. renewable power. Much of the pumped storage hydropower (PSH) is slated for the latter period, 2030-2050. Although the hydropower industry in the U.S. (and many other places) is considered mature and future opportunities are limited, there are still opportunities for better efficiency and to take advantage of new technology. Hydropower can provide baseload power that is renewable, reliable, predictable, long-lived, scalable, integrate-able with intermittent renewables, low-cost, and low-carbon. As a baseload source of power it can stabilize the grid during demand and during troughs in wind and solar generation. As pumped storage it can store energy in times of coincident low demand and high solar and wind generation and release it when needed. The DOE report notes that:

“By the end of 2015, the U.S. hydropower generation fleet included 2198 active power plants with a total capacity of 79.6 GW and 42 PSH plants totaling 21.6 GW, for a total installed hydropower capacity of 101 GW.” 

“Hydropower provided 6.2% of net U.S. electricity generation and approximately half (48%) of all U.S. renewable power in 2015.”

Ownership in hydropower generation is 49% federal government and 51% non-federal. In contrast most pumped storage is owned by utilities and makes up 97% of current utility-scale storage, although new battery storage and other forms of energy storage continue to be employed at utility scale. Ownership in PSH plants is 17% federal government and 83% non-federal. Most generation is fairly close to the coasts and higher population. Large projects occur in the Pacific Northwest. Most pumped storage is fairly near the Atlantic Coast. Hydropower capacity peaked around 2000 and has remained flat with only slight growth since then. Considerations for hydropower projects include other water uses (drinking, recreation, wildlife management, flood management, irrigation, and navigation), regulatory hurdles (which include regulations for ancillary services and grid integration of renewables and storage), and marketing hurdles, including proper valuation of storage and ancillary services. New hydropower projects are unlikely because it is difficult to meet sustainability requirements since damming often has negative effects on local ecosystems. Blocking rivers and flooding valleys for large projects is typically not popular with local populations either. Small-scale hydropower and new stream reach projects offers a very small potential for new projects with limited and small generation capacity. The barriers are technology and impacts on sustainability. This resource could grow significantly if these barriers could be overcome. As the Green Tech Media article notes:

“The {DOE} also announced $9.8 million in funding to develop low-head modular technologies to work at existing dams, as well as closed-loop pumped-hydro storage systems.”

Many full hydrokinetic resource evaluations have been done. One 2012 assessment done for the Continental U.S. by the Electric Power Research Institute along with the DOE’s National Renewable Energy Lab and the University of Alaska noted that technically recoverable and practically recoverable resource estimates could vary considerably. This evaluation noted that the highest technically recoverable resources are on the Lower Mississippi River followed distantly by Alaska then distantly by the Pacific Northwest then the Ohio River then the Lower Missouri River then the Upper Mississippi River. The Lower Colorado and Upper Missouri also have significant resources. 

Calls to Cut Regulatory Red Tape and Expedite Permitting

In a January 2016 op-ed in the New York Times, Alaska senator Lisa Murkowski and businessman Jay Faison argued that new hydropower projects should be pursued, especially on existing locks and dams on the Ohio, Mississippi, Arkansas, and Alabama rivers. Indeed, this is now happening on some of those rivers. They also complained about environmental compliance costs and the time it takes for re-licensing existing facilities so they can continue operating (exceeding a decade and $50 million in some cases). They mention bills that were in both houses to expand hydropower as part of the larger energy bill that Obama threated to veto. They also recommended “coordinating hydropower projects on a regionwide basis” to decrease permitting time and enhance environmental mitigation. They also mentioned new hydrokinetic technologies for converting tides, waves, ocean, and river currents into energy. Murkowski’s bill suggested giving permitting authority for hydropower projects to the FERC and to exclude other regulatory bodies like the U.S. Fish and Wildlife Service from the permitting process. While environmental groups charge that excluding the U.S. Fish and Wildlife Service, U.S. Forest Service, the National Park Service, and the Bureau of Indian Affairs from the permitting process would remove safeguards – there is little doubt that doing so would allow projects to be built faster and cheaper without such bureaucratic red tape. Murkowski’s argument is basically for expediting permitting for both new projects and re-licensing. Even the DOE recognizes these regulatory problems and suggests better cooperation between agencies. As in several other industries the permitting process has become cumbersome and needs to be more efficient. 

Assessing Environmental Impacts of Hydropower Projects

While large hydroelectric dam and reservoir projects are happening around the world, in China, Brazil, and a few in Canada for instance, there is not likely to be any new ones of this type in the U.S. Dams and reservoirs in low lying areas require more land to be flooded than those in hilly areas. This can change land use massively as it has in projects in Brazil where wildlife and indigenous peoples were displaced and in China’s Three Gorges Dam where many villages and villagers and were displaced. Forests may also be destroyed. While dams may provide some benefits like water for irrigation and recreation there are detriments as well. Sediment and excess nutrients tends to accumulate in the reservoirs and the water there is more stagnant than it otherwise would be. The excess sediment and nutrients may encourage algae and aquatic weeds. There is more water loss via evaporation at dammed reservoirs than in naturally flowing rivers. There is also the possibility of drying out areas downstream and negatively affecting wildlife if too much water is held back behind the dams. Turbine blades can kill and injure fish. Water can become lower in oxygen which can negatively affect wildlife. Some mitigation can be incorporated into projects such as aeration turbines to increase water oxygenation. Multi-level water intakes can be installed which leads to water being released that is more uniform in temperature and dissolved oxygen and more similar to what would have been the natural river water without the dam. Another issue with large dams, particularly those near the Pacific coast is that they withhold sediment from reaching the coast and building up beaches. This creates an imbalance of available sediment and supports coastal erosion of beaches.

Small ‘run-of-the-river’ hydropower facilities and dammed reservoirs in temperate lands general have small carbon footprints but large dammed reservoirs in tropical areas (also in temperate peatlands) can release much more carbon dioxide and methane during their life cycle. Flooding the land causes decomposition of the vegetation and topsoil. Emissions can vary considerably by project and should be modeled previously. Some areas can emit nearly as much greenhouse gases per kilowatt hour as electricity produced by natural gas but still far less than electricity produced by coal. However, the run-of-the-river projects are often nearly 20 times less in emissions than natural gas plants. The Gizmodo article notes that new studies suggest that there is 25% more methane being emitted under dammed reservoirs than previously thought. It also mentions a current boom in dam building around the world. It says that reservoirs (power, flood control, irrigation) account for 1.5% of global greenhouse gas emissions. They also state that 80 of the emissions from the flooded lands is from the methane.  

Recent studies have also found that dams of all sorts negatively affect biodiversity. This was a bit unexpected but the studies are conclusive and consistent for species of both plants and animals around dammed reservoirs all over the world. Dams also threaten riverine species such as otters as well as freshwater fish. Migratory fish like salmon are often deprived of reaching their upstream spawning grounds. One study of a Brazil dam estimated that only 31% of fish were making it upstream to spawn. Such losses can also affect fisheries downstream. There are 370 dams on the Mekong River in Southeast Asia and another 100 are planned. The fishing industry downstream is valued at $17 billion a year. Other ‘ecosystem services’ such as floodplain agriculture can be affected negatively as well as natural flooding cycles are altered. 

In the U.S. remediation of old dams is happening quite a bit. In 2014 alone, 72 dams in the U.S. were torn down or blown up thus restoring about 730 miles of rivers to more unaltered conditions. This has been happening for a few decades and most of the dams are old ones that have been out of use for some time. The Take Part articles notes that: “Eighty-two percent of the 1185 dams removed since 1912 have been taken out in the last two decades.” Pennsylvania and California removed the most dams in 2014. The most spectacular dam destruction was that of the 210 feet high Glines Canyon Dam on Washington Elwha River. This allowed Chinook salmon to return to ancestral spawning grounds after 100 years. The conservation group American Rivers has been instrumental in dam removal and river restoration.

  

There are also pleas from indigenous peoples to stop dammed reservoir hydroelectric projects, especially those that would be directly displaced typically in tropical countries. Several projects in the U.S. have flooded ancestral lands of Native American tribes including the graves of their historic persons. The grave of Seneca leader Chief Cornplanter from the early 19^th century is thought to lie under the Allegheny Reservoir which dams the Allegheny River in Northwest Pennsylvania. A hydroelectric dam in British Columbia, Canada is being contested by First Nations. An environmental impact statement concluded that the dam would flood nearby agricultural land and “result in the loss of some important multi-use, cultural areas and valued landscapes.” These would be permanent losses and a violation of treaty according to the contesting tribes. The tribes would have to sue through the courts but the current government is backing the project. It is also in-line with Canada’s clean energy goals.  

Powering Non-Powered Dams: Projects on the Ohio River and Its Tributary the Muskingum River

Large dammed reservoirs produce from hydrostatic resources while the energy extracted from rivers is naturally moving water, or hydrokinetic resources, that are captured with hydrokinetic devices such as turbines. Riverine hydrokinetic energy is the resource. 

The EIA reported in mid-July that nearly 300 MW of electric generating capacity is set to come online from the powering of previously nonpowered dams (NPDs). That makes up most of the total new capacity for 2016 of 320 MW. This is in contrast to only 126 coming online from 2006 through 2015. Total U.S. hydroelectric capacity in April 2016 was at 80,000 MW. About 1000 MW of hydropower were decommissioned from 2006 through 2015. 74% of the NPD hydropower from 2006 through 2016 are in the Ohio River. Total capacity on the Ohio River will be 554 MW. As of 2012 it was estimated that NPDs had the potential to generate 12,000 MW in additional capacity with 3000 MW being on the Ohio River, so that makes it seem likely that more additions will occur in the future. The Meldahl plant based in Foster, Kentucky has a capacity of 105 MW and supplies the city of Hamilton, Ohio. It is the largest producer on the Ohio River. Hamilton had been partly hydropowered since 1893 and since 1982 from a plant in further away Greenup County Kentucky. Their positive experience there led to interest in the Meldahl project. Such projects vary by state whether there will be subsidy incentives or whether they can be used to meet renewable energy mandates. In 2014 EIA projected just 2000 MW of new hydroelectric capacity by 2040. Approximately 16% of that is expected to go online in 2016 alone. The 2014 report also suggests that it is economics more than anything else that constrains these projects. There are three classes of projects: NPDs, New Stream Reaches which refers simply to newly built dam projects, and adding capacity to existing hydropower facilities. A study by the Oak Ridge National Laboratory assessed hydropower resource potential based on streamflow studies. That report also assessed hydrokinetic resources which utilize in-stream turbines. The resources are certainly there for more additions but economics are tough with many projects. 

Six new small hydroelectric are slated for Ohio’s Muskingum River which is a major tributary of the Ohio River. Total capacity for the six NPD projects combined will be 23 MW. The existing locks and dams are owned by the Ohio Dept. of Natural Resources. The developers are FFP New Hydro LLC and partner AECOM Capital. Construction for these projects is slated to begin in 2017 and be completed in 18 months. They are set to utilize engineering techniques to inject air into turbines to oxygenate the water and oxygenation levels are set to be monitored at each site.

The velocity of flowing water translates to the kinetic energy extracted. According to the Electric Power Research Institute U.S. hydrokinetic resource assessment  “The power available from hydrokinetic devices {mainly turbines}, per unit swept area is termed the hydrokinetic power density (PD, W m -2). Hydrokinetic power density is a function of fluid velocity (V, m s -1), fluid density (p, kg m -3), and device efficiency €.” The potential impact of the various hydrokinetic devices needs to be determined in order to maintain sufficient channel depth and velocity for navigation which is a very important source of transport on these rivers. 

Small-Scale Hydropower

Some companies are acquiring and developing small-scale hydroelectric resources strategically. They may be reliant on state renewable energy subsidies and/or favorable retail contracts with local customers. Federal, state, local, and/or regional laws can be impediments in some places. There are also those who want to invest in renewables projects and community energy projects. The key is probably identifying good resources and local customers that can be served and benefited compared to other local energy sources.

According to Greg Pahl in his 2012 book, Power From the People: How to Organize, Finance and Launch Local Power Projects, a major impediment to small-scale and community hydropower is permitting red tape as getting approval from FERC typically takes five years and significant expense. Such a long time frame is not conducive to profit generation for a business. It is a disincentive and this is basically the same argument Murkowski makes for larger projects. He did go on to mention FERC’s fast-tracking as part of their Small/Low Impact Hydropower program. Private companies and municipalities are exploring low cost/low output ''in-conduit projects with microturbines, which can replace pressure-reducing valves in pipes. Those have the fastest approval times. Pahl’s book case-studies several small-scale and community hydro projects. One in South Dakota had long permitting delays due to disagreements about permit conditions and jurisdiction between the state DNR and the U.S. Forest Service. – again similar to Murkowski’s red tape/delay complaints. The Meldahl project took over a decade to permit and required a big legal team, many consultants, and multiple regulatory agencies. Apparently, many of the Ohio River dams were built by the Army Corp of Engineers with the expectation that in the future they would be fitted with hydroelectric plants as better technologies became feasible. 

Riverine Hydrokinetic Technologies

According to the research paper by Long Pham at Oregon Tech there are two main types of hydrokinetic turbines: the axial flow turbines are more suitable to the needs of ocean currents and tides while the cross flow turbines are more suitable to riverine environments as well as being much cheaper and more durable since there are no sealed internal parts and the rotors can be connected directly. Both types are considered ‘low-head’ devices that can tap water power with low velocities due to lower head than say the large dammed reservoirs. As the DOE Hydrovision report notes the economics for the riverine hydro industry can be improved by manufacturing and using standardized and modular components and by incorporating mitigation technologies like oxygenation and low and easier and safer fish passage. New style such as the Archimedes Screw design are being used in some places and new compact turbine types and turbine/generator combinations are being tested and compared, some which eliminate the need for housing structures. 

   

References:

The DOE’s Path to an American Hydropower Renaissance – by Julian Spector, in Green Tech Media, July 27, 2016

Hydropower Vision: A New Chapter for America’s 1^st Renewable Electricity Source – by U.S. DOE, Office of Energy Efficiency and Renewable Energy, July 26, 2016

Several Nonpowered Dams Along the Ohio River to be Converted to Hydroelectric Dams in 2016 – By Energy Information Administration: Today in Energy, July 15, 2016

Is Obama Blocking Smart Hydropower Development? – by Ben Adler, in Grist, Jan 27, 2016

Stop Wasting America’s Hydropower Potential – by Lisa Murkowski and Jay Faison, in The New York Times, Jan. 14, 2016

Hydropower Dams Are Creating Wildlife Wastelands – by John R. Platt, in TakePart, June 3, 2016

Ohio Project Takes Advantage of Untapped Hydro Potential – by Douglas J. Guth & Midwest Energy News, in Green Energy Ohio, Vol 9, Issue 1, Spring, 2016

Canada’s Trudeau Promises to Do No Harm to First Nations, Does Harm Anyway – by Aura Bogado, in Grist, Aug. 3, 2016

Scientists Just Discovered a Major New Source of Carbon Emissions – by Maddie Stone, in Gizmodo, Sept. 29, 2016

Environmental Impacts of Hydroelectric Power – by Union of Concerned Scientists (2012, 2013)

This New Startup is Doing Hydropower Right – by Ben Adler, in Grist, Nov. 16, 2015

The Hydro Dam Boom Could Devastate Tropical Wildlife – by Taylor Hill, in TakePart, Jan 8, 2016

Dams are Being Blown Up All Over America, and That’s a Good Thing – by Taylor Hill, in TakePart, Feb 6, 2015

Environmental Geology, Fourth Edition – by Edward A. Keller (Charles E Merrill Publishing, 1985)

EIA Projections Show Hydro Growth Limited by Economics Not Resources – by EIA, Today In Energy, July 10, 2014

Power From the People: How to Organize, Finance, and Launch Local Energy Projects – by Greg Pahl (Post Carbon Institute/Chelsea Green Publishing, 2012)

Assessment and Mapping of the Riverine Hydrokinetic Resource in the Continental United States: 2012 Technical Report – by Electric Power Research Institute (EPRI), Final Report 1026880, Dec. 2012

Riverine Hydrokinetic Technology: A Review – by Long Pham – Oregon Tech REE516 Term Paper, March 2014