Hydro power has been part of Cornell's energy supply since the 1880s...
Complete upgrades to the existing hydroelectric plant to optimize electric generation.
Goal: Upgrade Cornell’s existing hydroelectric plant to optimize electric generation. When completed, plant upgrades are expected to increase electric production by 1 million kWh per year and reduce greenhouse gas emissions by 450-600 metric tons per year.
Fall Creek has played an important role in Cornell’s history since Ezra Cornell first arrived in Ithaca in spring 1828. According to The Ezra Cornell Bicentennial Exhibition, “Ithaca in the 1820s was a growing community. Water from the creeks powered lumber, flour, plaster, paper, cotton, and woolen mills… Cornell first found work as a carpenter, before being hired as a mechanic by Otis Eddy to work at his cotton mill on Cascadilla Creek. On Eddy’s recommendation, Jeremiah S. Beebe then hired Cornell to repair and overhaul his plaster and flour mills on Fall Creek. During Cornell’s long association with Beebe, he designed and built a tunnel for a new mill race on Fall Creek; a stone dam on Fall Creek, which formed Beebe Lake; and a new flour mill. By 1832, he was in charge of all Beebe’s concerns at Fall Creek.” See http://rmc.library.cornell.edu/ezra/exhibition/ithaca/ for more details.
The first electrical generation facility in Fall Creek gorge was built in the early 1880s. That plant was powered by water from a dam just above the present plant and a cable to a generator located near the Cornell Foundry. In 1904, the plant was built in its present site under the Suspension Bridge.
Water is supplied to the plant from Beebe Lake by a five-foot diameter underground penstock, which is 1700 feet long. The water is then directed to one of two turbines, causing them to spin and drive an induction motor – thus generating electricity. Cornell’s hydroelectric plant is “run of river,” which means that no water is stored. At all times, 10 cubic feet per second of water must continue to pass over the dam. The average production for the plant is 4.5M KWh to 5.5M KWh per year depending on rainfall.
Both of the 30-year-old turbines have been rebuilt. Other plant upgrades include the restructuring of the intake, relining of the penstock, and possible optimization of the draft tubes. When the turbine upgrade project is completed, it will allow complete remote starting of the units – which will enable Cornell to take advantage of increased flows and operate two turbines (for example, during rainfall events) to generate more power without the need for manual adjustments.
- Design and rebuild the intake to reduce head losses and increase plant efficiency by 10%. Planned for 2017.
- Investigate installing a smaller, more efficient turbine for low summer and winter flows.
- Investigate modifying the plant’s Federal Energy Regulatory Commission operating license to permit partial water storage at Beebe Lake – which would enable electric generation at peak daytime hours during the summer months.
- Reline or rebuild and resize the penstock to reduce head losses at peak production times.
Most other renewable power sources are subsidized to offset high installation costs. If hydropower customers at the University paid a premium for their hydro-electricity, the rate of payback on the investment in plant upgrades would be considerably shorter than it is currently.