Small Hydropower: A renewable resource that could sweep the nation

Hydroelectric. Hydropower. Hydro. Whatever you call it, it’s all the same: a renewable, non-polluting, and reliable source of energy—an ideal solution to our nation’s immediate demand for renewable energy sources. Yes, hydropower could be the greatest power source available, in more ways than one. Unlike fossil fuels, it’s not rapidly depleting; unlike coal and nuclear energy, it doesn’t create hazardous byproducts; and, unlike solar and wind energy, it’s not dependent on weather conditions, so its supply can be increased or decreased according to demand.

Although only eight percent of the total United States electrical power was generated by hydroelectric power plants in 1999, the nation’s 2,000 hydropower plants make hydroelectric power its largest renewable energy source, a remarkable 49% of all renewables. Add to this the nearly 78,000 existing dams and countless other water features (e.g. pipelines, streams, irrigation ditches) that have a potential for creating hydropower, and we have a formula for successful renewable energy: retrofitting existing dams and other water features. According to the US Geological Survey, the likely trend for the future is toward small-scale hydroelectric power plants (or powerhouses) that can generate electricity for single communities.

“The definition of small hydro varies, but typically these projects are 20 megawatts or less,” says Alden Robinson, president of Sunrise Engineering. “And, since most of the viable projects out there today are less than five megawatts, there’s a lot of potential for small hydro. We need to be forward-thinking in where hydro can be used. Why don’t we put hydro on existing reservoirs and pipelines?”

Thankfully, as more and more energy users expect affordable, renewable, clean power and, as our nation confronts an overwhelming need to produce our own energy sources, public works districts, public agency leaders, and facility owners are realizing that part of the solution is right in their own back yard—on existing water infrastructure. Many communities may need to turn a critical eye to their existing dams and infrastructure to recognize their own possibilities for small hydro. But how does a community recognize these opportunities? And, how do they take an existing opportunity and turn it into reality?

Though the motivations for projects like this may differ, the process is formulaic: determine the feasibility, get the funding, obtain the license, and build the project. For the Town of Afton, Wyoming and the regional energy provider, Lower Valley Energy, the process of rehabilitating and retrofitting the Swift Creek Dam began with the motivation of cleaning up a run-down eyesore, and with total support from the community. The Swift Creek Hydroelectric Project is located in Swift Creek Canyon, a popular tourist and local hiking spot, partially within the Bridger-Teton National Forest near Afton, Wyoming. Originally licensed in 1942, the project includes two diversion dams, each with a powerhouse, and 2.5 miles of penstock. The project operated until 1968 when the penstock was damaged by an avalanche. Over the years, the two powerhouses were stripped and fell into disrepair. The facility became an eyesore in what was otherwise a picturesque canyon. With this dilapidation came increased liability—Swift Creek boasts a siphoning spring that attracts thousands of tourists each year.

In the early 90s, the project’s Federal Energy Regulatory Commission (FERC) license expired. The Town of Afton successfully obtained a new license, which mandated that they either remove the remaining hydroelectric structures or get the project running again. After much debate and deliberation, the major players—the landowner, the Bridger National Forest Service; the license holder, the Town of Afton; and the regional utility provider, Lower Valley Energy (LVE)—agreed the project should be rehabilitated.

Afton and LVE created an equal partnership for the project. They brought on Symbiotics LLC and Sunrise Engineering for their expertise to design, reconstruct, upgrade, and restore the two historic powerhouses, the nearly 9,000 feet of penstock up to 48" in diameter, and the dam itself. The total project cost came to around seven-million dollars, according to Chad Jensen, LVE’s vice president, and it will generate an estimated 1.5 megawatts of power—enough to power 2,250 homes.

Penciling out the project’s feasibility and details is necessary to determine the project’s return on investment based on accurate forecasts of costs including debt service, site purchase, construction, licensing, operations, and maintenance. It is essential to know ahead of time whether the power can be sold for more than what it costs to produce, whether the powerhouse can be operated to generate the power that is needed, and whether private investment or bonding will be needed—as well as if either of them is practical based on the specific project and situation.

“Small hydro powerhouses can last between 80 to 100 years, or indefinitely with the proper maintenance,” Robinson notes. “Once construction is complete and debt service is paid over 20 years, you have essentially free power for at least the next 60.”

Design is also a big component of this type of project’s success. Understanding the various methods to prevent environmental impact, such as providing safe fish passage, is crucial. Because these projects are located on existing waterways, many of which are community attractions, it is important to minimize aesthetic and visual impacts.

In the end, the proper feasibility, funding, and design can all combine for a successful project that is suited to produce renewable energy for years. The Afton project is an ideal example in that they used feasibility, funding, and design to gain community support. Bill Spaulding, LVE’s project manager for the Swift Creek project, who worked on the neighboring Cottonwood Irrigation system hydropower project back in 1971, perhaps, says it best: “Cottonwood was only a two-year project that is still producing hydropower today, and working great. Hydropower is an untapped renewable resource and in the history of our nation, no matter what, hydro is still king.”

Beth Fillerup is a freelance writer with over 20 years of experience marketing and writing for the A/E/C industry with particular focus and interest in sustainable communities, sustainable building, and water quality.

Sunrise Engineering
www.sunrise-eng.com