Cloverland Electric Cooperative Hydroelectric Plant

Construction of the landmark hydroelectric plant facility was completed in 1902. At that time, it was the second largest hydro facility next to Niagara Falls.

The hydro plant is constructed of steel and red sandstone. The stone was excavated from the power canal. The plant is a quarter mile long, 80 feet wide and has 74 horizontal shaft turbines located on the generation floor level. Each turbine has four runners (blades) that drive the 60-cycle generators. The water, which flows down the power canal, drops through gates in the turbines to make them spin, like a child’s pinwheel in the wind. The turbine turns the rotor—the last moving part. The turning creates electricity. To learn more please watch this video.

Under ideal operating conditions, the hydro plant is capable of producing about 36,000 kilowatts (36 megawatts). Power output depends on the volume of water traveling through the power canal and the plant’s operating head. The operating head is the difference in water levels at the plant’s forebay (upriver) and the tailrace (downriver) on the St. Marys River. This difference is equivalent to the drop in elevation between Lake Superior and the lower Great Lakes.

Plant production follows the swings of seasonal climate fluctuations and weather patterns. Power production has remained relatively steady over the decades notwithstanding the changes in water supply and flow restrictions.

Although percentages fluctuate monthly, renewable hydroelectric power accounts for about 40 – 50% of Cloverland’s power supply annually. The hydro plant generates about 30% of the hydroelectric power. An additional 20% is generated from the U.S. Army Corps of Engineers hydro plant located in the Soo Locks.

Architecture

Local architect, James Calloway Teague, designed the plant in 1899 to give the impression of power, importance and stability. The Romanesque design included three large pavilions and a double-pitched roof to counterbalance the length of the plant.

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Powerful Facts

• Cloverland’s maximum output is 36 megawatts and the plant average is 26-28 megawatts daily. By comparison, the Canadian plant in Sault Ste. Marie, Ontario, produces 45 megawatts, and the US Corps of Engineers plant at Soo Locks has a maximum output of 21 megawatts and averages 18 megawatts daily.
• At peak operation, the plant discharges approximately 30,000 cubic feet of water per second (equivalent to about 13.5 million gallons per minute).
• The hydro plant consists of 74 three-phase generators. Each 60-cycle generator operates at 4400 volts, 180 RPM. Each turbine supplies enough power for roughly 250 average homes, assuming each uses around 3-4 kVA at peak demand
• With 20 feet of headwaters falling from the upper St. Marys River to the lower river, rated output of the turbines is 772 to 935 horsepower.
• Three manufacturers (no longer in existence) built the turbines. Many replacement parts are now machined in-house.
• Canal water velocity is seven to 10 feet per second, or five to seven miles per hour.
• Most of the heat needed for the building during the winter months is generated by the operating equipment.
• The plant increases electricity production when the demand for electricity is highest (8 a.m. to 9 p.m.) and reduces production at all other times during periods of insufficient water allocations.
• Some of the original wood bearings for the turbines are still in use today. The bearings were made from lignum vitae, a rare dense wood found in Central and South America. The natural oils in this wood make it an ideal solution for water lubricated bearings. It is superior to most other man-made materials for this purpose.