Rural Rites: Wind power harnessed for power

By MINDY POEHL | Central Texas Edition

A longtime friend to farmers and ranchers has been the windmill. Especially where electricity is not available the windmill has served as the element for bringing water to parched areas. -- Photo by Carolyn Rost

August 25, 2005 - A windmill can be an option for using "free energy" to generate water. A windmill utilizes the free, and renewable power of the wind and uses that energy to lift underground water to the surface.

But where does one go to purchase a windmill? Check out area farm equipment companies or call companies listed under "water utilities" in the phone book. Or, visit the Texas Ground Water Association website (www.tgwa.org/index.html) that lists information for various areas of Texas.

Terry Williams, part owner of Reimer Pump Sales and Services in Waco, said he mainly provides windmills to people in remote areas, where electricity is not readily available.

"People also use them as a decoration and (as a source for) water for their cattle or their homes," Williams said.

Windmills were introduced in the 1800s in Texas, making it possible for settlers to pump water from beneath the ground. Williams said two companies that produced windmills in the 1800s are still manufacturing windmills today: Aermotor, located in San Angelo, and Dempster, located in York, Neb.

Windmills were introduced in the 1800s in Texas, making it possible for settlers to pump water from beneath the ground. Williams said two companies that produced windmills in the 1800s are still manufacturing windmills today: Aermotor, located in San Angelo, and Dempster.

In 1888, the first all-steel mill was produced. Most farmers and ranchers welcomed the new steel windmill because its galvanized wheel and tower held up in harsh weather conditions. Its gear system was also better able to take advantage of the wind, enabling the windmill to run for longer periods of time. In was in this era that Texas became the largest user of windmills in the United States.

Many people wonder how a windmill works. Because windmills are efficient and resilient, the basic design has not changed in almost 120 years. The windmill harnesses the wind's energy to power a water pump located deep under ground.

"The windmill turns a gear box and it moves the sucker rod in an up-and-down motion, which pumps water out of the cylinder," Williams easily explained.

The top of the windmill has the most notable feature -- a large, circular fan, that can be turned by the wind. Below the turning fan, or wheel, a "sucker rod" is moved in order generate power to the windmill's motor. This motor converts the rotary motion of the wheel into power for the cylinder pump located deep underground.

A water well, that's below the windmill tower, is a small-diameter hole drilled into the Earth's crust that fills up with water. As the well is drilled, it passes through various underground layers of sand and gravel, and extends into an aquifer, or underground water-bearing formation.

The top of an aquifer is called the "water table." The depth of this water table is important because it determines how deep a water well must be drilled. It also determines the size of the windmill required to pump water to the surface.

Once the well is drilled to the proper depth, the well wall is reinforced and permeated to allow water from the aquifer to seep into the well. Gravity causes the water to rise to the level of the underground water table. A sealed "drop pipe" is then inserted into the well until its lower end is fully immersed in the well water.

The cylinder pump does not use high-powered suction. Instead, it builds a column of water from the aquifer to the surface within the drop pipe, from the bottom upward. Two pump valves work together to draw well water into the bottom of the drop pipe and help move the water column upward. By repeatedly adding water to the bottom of the water column, the drop pipe fills and water pours out of the top into a storage tank.

This completes the working process of the windmill.

Williams said his company seldom installs windmills on people's property. However, there are several companies in West Texas that specialize in setting up and repairing windmills.

"You can buy second-hand and refurbished windmills, but it is sometimes hard getting parts for them," Williams said. "Windmills are largely used in third world countries. And I ship windmills to Old Mexico and Haiti. Many people buy them just because they want a windmill on their place."

Williams said the minimum price of a new windmill is $3,000 to $4,000, that is not set up and does not include parts, such as the cylinder and sucker pipe.