What is Hydropower?
Hydropower uses the energy of falling water to do work, either to move machinery or generate electricity. Originally, a metal turbine underneath the gristmill harnessed the power of Fleming Creek. Water from the old millpond flowed through an underground channel into the mill, spinning the turbine blades. A main driveshaft transferred power from the turbine to a series of gears, shafts, pulleys and belts that operated the equipment in both mills. A simple turbine is illustrated here. In 1978, a flood destroyed the dam and millpond. Today, the mill still grinds corn thanks to the installation of an electric motor in 1985.
Where did the Water Go?
Follow the red an blue arrows to learn how the water flowed through the mill and then back to Fleming Creek...
1 Water from the millpond flowed into an underground channel called the "headrace"
A dam just upstream of the Geddes Road bridge, created a millpond which raised the water level by several feet. Raising the water level is important. The farther water has to fall before hitting the turbine, the more energy it will have and the more power it can generate. Water from the millpond flowed into the headrace channel and down to the turbine, located 20 feet below the lower floor of
2 Flowing water spun the turbine blades and generated power
Water flowing downhill through the headrace picked up enough speed to spin the turbine blades. The main driveshaft connected to a large gear called a bull gear, which was connected to more gears that operated the millstones, sifters, grist elevators, grain cleaners, and so on, even a lathe!
3 Water flowed into the "tailrace"
After the water turned the turbine blades, it flowed through the hollow center of the turbine and into another underground channel called the tailrace. At this point, the water has given up most of its energy.
4 Water in the tailrace flowed back into Fleming Creek
Question: Where does the water flow faster, in the headrace or the tailrace?
The King of Turbines
In 1924, Geddes Road was raised, widened and paved. At the same time, the Parkers raised the stone foundations of the mill buildings, replacing the original wooden-paddled tubwheel with a smaller, more efficient metal turbine.
The 24" Double Perfection Water-Wheel
has two wheels stacked one on top of the other. A gate was used to control the flow of water to the turbine. With the gate half opened, one wheel received 700 cubic feet per minute (cfm) of water and generated approximately 15 horsepower. At full gate, both wheels used double the water and gave double the power!
Question: What are some other benefits of having TWO water wheels in the turbine instead of just one?
Fun Facts about Hydropower
- The Greeks were the first to use water power to grind grain around 19 B.C.
- Michael Faraday created the world's first hydroelectric generator in 1831.
- In 1880, Michigan's Grand Rapids Electric Light and Power Company was the first to combine a water wheel and a generator to produce hydroelectric power.
- Percentage of U.S. energy supplied by hydropower:
- 1907: 15%
- 1920: 40%
- 1940: 25%
- 2000: about 7%
- Unlike oil or coal, which exist in limited amounts on earth, water is a renewable resource, meaning that it can be recycled again and again to generate power.
- The highest dam in the U.S. is the Oroville Dam in California, which is 754 feet tall—about as tall as a 60-story building—and a mile wide. The highest dam in the world is the Nurek Dam in Tadzikistan in central Asia. This dam is 984 feet tall!
- One of the most famous dams in the U.S. is the Hoover Dam, built across the Colorado River in 1946. It is 726 feet tall and stores enough water in Lake Mead Reservoir to cover the State of Pennsylvania to a depth
Original catalog features the "Double Perfection" turbine on the cover. Manufactured in Pennsylvania by Craig Ridgway & Son Co. Sold for $324 in 1924.
Courtesy of Parker Familyof 1 foot! The dam provides power for the states of Arizona, Nevada and California.
ANSWERS: 1) The water flows faster in the HEADRACE; 2) When water levels are low, the turbine could still operate with only one wheel. Also, if a mill owner knew he was going to add more machinery later on, he could run the double wheel turbine at a lower horsepower until he needed full power.
Visit Sharon Mills County Park, in Sharon Township, to see another example of a hydropowered mill!