For the more than 25,000 farms spread across the rural landscape in New Mexico, electrical power isn’t always readily available. Windmills have long been the traditional source of pulling water from wells at remote agricultural outposts, but now, solar panels may be popping up in place of these icons of the American West.

New Mexico State University’s College of Engineering and the Cooperative Extension Service are teaming up to show New Mexico’s farmers and ranchers how they can use alternative energy in their business. Extension officers can now provide live demonstrations with a portable solar-powered water pump.

“There are a lot of producers looking for alternative power options,” said Bruce Hinrichs, associate director of the Cooperative Extension Service. “It’s difficult for them to know where to start when they are considering new technologies.”

Tom Jenkins, professor of engineering technology and head of the department’s renewable energy program, has been working with the Extension service to produce training presentations explaining the use of renewable energy sources in agricultural applications. Taking the idea further, Extension officers wanted to be able to demonstrate to the agricultural community in the state how solar power could be used to pump well water.

Students work on the problem

Jenkins, acting as a client, presented a group of mechanical engineering technology students with the problem.

Three students took on the problem as their senior capstone project in the spring 2011 semester. Senior capstone design courses are the culmination of the engineering curriculum at NMSU, requiring students to utilize knowledge and skills acquired throughout their coursework.

Under the tutelage of Craig Ricketts, associate engineering technology professor, Cody Anderson, Felicia Costales and Andres Galvan designed and built a portable demonstration unit that could be taken into the field.

The unit consists of a rolling cart outfitted with a small solar panel that collects heat energy from sunlight and converts it to electricity. The electricity powers a high-pressure submersible pump in a 50-gallon storage vessel. The pump is equipped with a sophisticated control box that optimizes the power needed to control the speed of the pump. Meters show the current and voltage produced by the solar panel and used by the pump.

“A major engineering challenge of this project was for the students to come up with a method to simulate different depths of water in a portable unit,” said Jeff Beasley, engineering technology and surveying engineering department head.

The students incorporated a valve to control water pressure so the unit can simulate pumping from depths up to 400 feet, using mathematical equations to determine the correlation between water pressure and depth.