Hydro for higher education24 March 2022
With the recent completion of a hydroelectric generating station on the Kentucky River in the US, Berea College is leading by example when it comes to reducing carbon emissions.
Berea College is the first higher education institution in the US to complete construction of a hydroelectric generating plant. The US$11million Matilda Hamilton Fee Hydroelectric Station, named after the ‘First Lady’ and a co-founder of Berea College, is the first new hydropower facility built in the state of Kentucky in 94 years. It is also the first of its kind to use a combination of modern technology and existing infrastructure.
The result is that about half of Berea College’s electric power demands will be offset by this source of clean, renewable energy. Future plans to build a second hydroelectric station on the river will compensate for the other half of the college’s electric usage. And, if the carbon captured by the Berea College Forest is taken into consideration, the college’s carbon footprint will be negative in the future. (Although technically, the carbon credits created by the forest are sold in the California carbon credit market, so that absorption doesn’t really count against the college’s footprint; it is offsetting someone else’s.)
“The hydroelectric generating plant shows that local green initiatives like this one can be financially feasible and create reliable sources of income and acceptable rates of return on investment,” said Berea College President Lyle Roelofs. “At the same time, it displays to our students and everyone else both the college’s commitment to environmental sustainability and the viability of state-of-the-art renewable energy technologies.”
Roelofs goes on to describe the technical details of this 2.64MW hydropower demonstration project on the Kentucky River near Ravenna in Estill County as “dazzling”.
“Our engineering partners, Appalachian Hydro Associates (AHA), engineered the re-use of an existing, century-old lock and dam structure to house the power plant, providing a significant cost reduction,” he went on to explain. “The lock at dam 12 had been out of use and welded shut since the 1990s, and until now, the water flowing over the dam represented wasted energy.
“AHA ‘shoehorned’ five 528kW submersible turbine generators into the abandoned lock. Submersible generators are necessary for this application because they are unaffected by flooding, a frequent reality on our state’s fickle river.”
A project ten years in the making, the Ravenna hydroelectric plant is the result of a robust collaboration that includes Appalachian Hydro Associates, the Kentucky River Authority, Jackson Energy Cooperative, Wright Concrete & Construction of Pikeville, Kleinschmidt Group, Xylem and Berea College.
How It works
By “shoe-horning” a hydro powerhouse into an abandoned navigational lock, AHA significantly lowered the project’s construction budget. Flygt submersible turbine generators, developed by water technology provider Xylem, are not affected by the frequent flooding of the Kentucky River and offer reliable, efficient means for generating power. The generators have an efficiency of 96.8%, giving the units an overall efficiency of 81.1%.
The Flygt turbine generators are designed to last 50 years, helped by the application of Polyset which prevents rust on the units. This is the same zinc silicate coating used on US Navy aircraft carriers. It forms a chemical bond with steel and creates an impermeable glass-like surface. In comparison, conventional steel coatings last only 15 years before rusting.
Furthermore, the project is the first new hydroelectric plant in the US to use Variable Speed Technology. Borrowed from wind power, variable speed drives allow the turbines to operate at maximum efficiency as the river levels change, which increases net energy output by up to 15% over conventional fixed speed turbines.
The variable speed drives also correct the low generator power factors, eliminating the need for power factor correction capacitors. In addition, they allow the power plant to easily sync to rural power grids with an existing distribution line - a significant cost saving.
Berea College arranged funding for the project, investing some of its own funds and also making use of federal and Kentucky market and investment tax credits with assistance from key financial partners.
“The power generated by this facility is being sold to Jackson Energy Cooperative at a discounted rate, so its customers ultimately benefit as well,” Roelofs said. “The US$11 million construction cost of the project was partially offset by various available tax credits resulting in an acceptable rate of return for the college even after the discount. So, this project is a win-win-win: it’s a great long-term investment for us, but it’s also beneficial for the community and it’s the right thing to do for the climate of our planet.”
The area around lock and dam 12 has also been improved to include a pavilion with picnic tables for the benefit of local residents and a portage way for kayakers on the river.
Revenue generated by the project will be funnelled into Berea College’s general fund to support the mission of educating students of limited financial means.
“We’re glad that the money, the investment, is being used to teach students that otherwise couldn’t go to college,” said Robert Fairchild, Vice President of AHA. “We believe in the mission of Berea College as well.”
Completed in late May 2021, the plant will also create new learning opportunities for Berea College students while helping fulfil the college’s commitment to environmental sustainability.
Roelofs said: “Our students learn the science of sustainability and the importance of household-level activities like recycling or purchasing an electric vehicle. As we look toward a better, cleaner future, these same students will understand, as well, the opportunities at the institutional level. Through our demonstration project, we aim to show them and all other Kentuckians that environmentally sustainable projects are not only financially feasible and attractive, but also the right thing to do at this point in time.
“We must all take action against global climate change, and sooner rather than later,” Roelofs urges. “Our collective future and economic success depend on it. The Matilda Hamilton Fee Hydroelectric Station is one example of how we can work together to address these challenges.”
College officials say that they are also considering repurposing lock and dam 14 at Heidelberg in Lee County as a second hydro station.
“We don’t want the students just to think about sustainability as an abstract concept. We want them to see that to really pursue sustainability, you do big things like this,” Roelofs said.
IWP&DC would like to thank Berea College for its kind permission to reproduce the information and photos used in this article.