Construction is partially complete for 54,000 power plants that are poised to supply four million American homes with inexpensive, renewable energy that will have virtually no negative impacts on the environment. The required equipment has been field-tested for decades and is effective and highly reliable. It’s already being manufactured worldwide by companies like General Electric. And new research suggests that significant breakthroughs are imminent in the efficiency and flexibility of the generating technology. Most of these facilities are government-owned, and all are capable of reliably supplying electricity to the transmission grid without any modifications to the existing system.
If this sounds too good to be true, read on.
According to a new study, published in April 2012 by the U.S. Department of Energy’s (DOE) Wind and Water Power Program and carried out by Oak Ridge National Laboratory with input from Idaho National Laboratory, the United States can quickly add 12,000 megawatts of renewable energy capacity to the grid by adding hydropower turbines and generators to dams that already exist for other purposes like flood control, water supply, navigation and recreation.
Because the dam structures are already in place (many for decades, some for a century), the addition of generation equipment would not have a negative effect on surrounding sites. In a more profound sense, the environmental impact would be tremendously positive because the hydro plants would offset the use of fossil fuels, especially in states like Kentucky that depend on coal for more than 90 percent of electricity production.
The same DOE study estimates that Kentucky’s total potential hydro capacity at currently non-powered dams is greater than 1,700 megawatts. A more measured analysis, however, by one of Kentucky’s most respected renewable energy teams, Soft Energy Associates, (renovator of historic hydro projects on the Kentucky River, Elkhorn Creek and elsewhere), puts the feasible statewide estimate at 849.54 megawatts.
Even this conservative estimate is very good news. Although the 850 megawatts of hydro represents only about 5 percent of the total amount of electricity generated by coal-fired power plants in our state, every megawatt of generating capacity supports the energy needs of about 500 standard homes. Retrofitted dams in Kentucky could provide enough hydropower for about 425,000 homes. (Compare this to the 250,000 homes served by a large coal-fired plant like Kentucky Utilities’ E. W. Brown generating station in Mercer County.)
By offsetting the use of coal, these projects would immediately prevent more than a million and a half pounds of carbon dioxide from entering the atmosphere every hour. Every hour, less nitrogen oxide, sulfur dioxide, mercury, chromium, arsenic, ozone, soot, fine particulates, droplets of acid, and combustion waste (fly ash, bottom ash, scrubber waste). Every hour.
Two hydropower companies currently developing plants in Kentucky at retrofitted dam sites serve as important models for two reasons: They build public confidence in hydropower’s feasibility, and they help the government agencies that own the dams and control river issues, i.e., the Kentucky River Authority (KRA) and the U.S. Army Corps of Engineers (ACOE), to establish protocols for future projects in which private entrepreneurs want to retrofit dam sites.
The renovated Mother Ann Lee Hydroelectric Station at Lock and Dam number 7 on the Kentucky River has been completed, is operating profitably and is steadily improving efficiency. The smooth success of this project helped convince the Kentucky state legislature in July 2008 to make the development of low-impact hydropower part of the operational mandate for the KRA. Three new facilities are under construction at very large, existing lock and dam structures along the Ohio River — Cannellton, Smithland and Meldahl — and will be capable of producing 261 megawatts.
Preliminary permits have been issued by the Federal Energy Regulatory Commission (FERC) for 21 other projects on the Ohio, Kentucky, Salt, Licking, Barren, Green and Nolin rivers. These could provide an additional 586.5 megawatts of generating capacity. A number of these existing dams, like those on the upper Kentucky River, also have defunct lock chambers that would be used to temporarily dewater space in the river for construction and maintenance and therefore significantly reduce initial development expenses.
The cost of retrofitting these lock and dam structures is about $2.5 million per megawatt of capacity. Thus, for a total of $2.125 billion, Kentucky could boast 850 megawatts of perpetual renewable energy.
With hydropower, consumers’ energy bills would be lower and more stable. Energy customers in Kentucky have recently been subject to annual rate increases of more than 16 percent. This is, of course, unsustainable, especially in a state that is sixth poorest in the country. After construction is complete for a hydro plant (or other structural renewable generation system, like wind or solar), there would be virtually no expenses beyond predictable maintenance costs and efficiency upgrades.
Most importantly, there would be no fuel to purchase or emissions to manage, ever. Contrast this with a plant like E. W. Brown in Mercer County that burns about a million and a half tons of expensive coal a year. A ton of coal, delivered to a typical coal-burning plant, costs about $45. (This price is likely to rise, especially from mines in Appalachia, where access to coal seams is increasingly difficult and unnecessarily destructive.) Therefore, just to purchase raw fuel, a plant the size of Brown is likely to spend more than $67,500,000 per year.
The other perpetual expense associated with coal-fired power plants is the prodigious quantity of toxic waste produced. Building and operating emissions scrubbers, as well as processing and storing solid and liquid wastes, is a cost that coal-fired generation plants also pass along to customers.
Hydropower is also exempt from the hidden “externalized” costs that are passed on to everyone and are not reflected on consumers’ electric bills. The list of damages from fossil fuel-based power is long (and well-documented elsewhere), including the health costs to miners (black-lung, silicosis, mining accidents, poor work conditions, job insecurity, etc.); significant quality-of-life costs to coal-field residents (ruined property, devastated water supply, poor air quality, hazards from slurry impoundments, road damage by mining and conveyance vehicles, etc.); and damage to the environment and to the world at large (rapid climate change caused by carbon dioxide emissions, toxicity of soil and water resulting in high levels of mercury and other toxins released by mining and combusting fossil fuels, and the loss of valuable ecosystems, topsoil and habitat).
As we make more use of hydro and other structural renewable sources, the generation technology will continue to improve so that more energy can be made from the same amount of water, wind and sun that we already have. Right now in Kentucky, for example, Soft Energy Associates is using a prestigious 2011 DOE grant to evaluate the efficiency of variable speed, permanent magnet generators for low-head hydropower at small sites like the Weisenberger Mill project near Midway, Ky.
Renewable energy developers are eager to invest in Kentucky in part because the transmission grid here is more accessible and is in better condition than in many other states. A surge in sustainable energy from resources at hand, like existing dams, would set a powerful example, especially in a state that has historically been dominated by the coal industry. West Virginia, by contrast, has very little hydro power capacity, despite the fact that several large, federal flood-control dams in the region, e.g. Bluestone and Tygart, were originally designed for that purpose; penstocks were built into the original structures but never put into service because of resistance from the coal industry.
We have dams and a healthy grid. Let’s not squander this excellent potential to make cheap, clean, renewable power for some of Kentucky’s needs. Five percent is not enough, but it would be a good, solid start.