Engineering Student Designs a Windmill for an Indian Village in Mexico
By Tony and Alison Martinez
Ryan Wotipka built the turbine that won first prize out of junkyard parts. Even so, the college senior admits it was tough to buy what he needed while working his way through the University of Texas San Antonio on mechanic and handyman odd jobs. “I was eating rice every day. But it feels good. I can eat rice for a while if it means doing something good.”
A native of Schulenberg, Texas, Wotipka can afford more luxurious groceries now that he has won the thousand-dollar top prize in the University Energy Leadership Contest at San Antonio’s 2004 Emissions Reduction and Energy Summit. His winning entry harvests the strong winds of Mexico’s Copper Canyon region to provide electric power to a “green” school building serving youth of the impoverished Tarahumara Indian tribe.
“The Mexican government is sawing down all the trees,” in the Tarahumaras’ mountainous homeland, Wotipka says. “Without trees, the earth erodes, and game animals don’t come. They dump the sawdust in the river. It kills the fish. The Indians can’t farm, hunt, or fish. The young people all go to the city and try to get jobs,” but jobs are scarce. The tribe has founded a school and cultural center to carry out a reforestation program adapted to local conditions and to reintroduce traditional skills such as farming and weaving. “That way, the teenagers can stick around and be proud of who they are.”
To build the facility, the usually independent-minded Tarahumara tribe asked outsiders for help. One organization they asked is Mexico North, Inc., a nonprofit consortium of 34 U.S. and Mexican universities, museums, research institutes, and cultural organizations, including the University of Texas San Antonio. The consortium provided $15,000 to send 15 students from San Antonio, Texas to Norogachi, Chihuahua for six weeks in summer, 2004. The students helped design and build the boarding school while learning energy-efficient, traditional construction techniques.
“The school is on top of a mountain, totally off the electrical grid,” Wotipka relates. “They were thinking of just solar power, but I had read you can build wind turbines out of car alternators, so I pitched the idea of small-scale turbines,” with solar power for backup. “As I did my research, I learned you can do it way more efficiently. You can make really good home-built rigs, still out of scrap but much more efficient than the car alternator version.”
Wotipka credits Scotsman Hugh Piggott, a leader in the home-built wind-generation movement, with the insights that led to his design. “The basic thing is the permanent magnet alternator,” he explains. “It has the same power output as a ten-foot rig you might buy from a green power store, but there are no brushes to wear out or replace. The magnets never touch anything.” He continues, “I use rare earth magnets out of old computer hard drives. These are the strongest magnets in the world. The ones I use are about the size of a domino, and if you’ve got a couple in your hand, you’d better keep your fist closed, because if you get near a mass of steel, if you don’t keep your hand closed, the magnets will fly eighteen inches or two feet and bust your knuckle.”
Wotipka calls his design “the same as in big coal and gas plants, but instead of steam, wind turns the turbine.” Two rotors with magnets placed in opposite polarity form a sandwich around wire coils. Because even atop a tower on a mountain, wind moves slower than the high-pressure steam from burning fossil fuel, the wind turbine is geared to produce electricity at lower rotational speeds than steam turbines.
“When you build with scrap, you can really overbuild,” Wotipka adds. “My turbine is based on a Chevy 4×4. It’s strong, dependable, and low maintenance. Turbines you buy at a store are meant to be packed and shipped, so they’re lighter weight. Light weight is not always advantageous once it’s in use.”
Mexico North brought the student and his turbine back to the construction site this spring to install the system. On the same trip, Wotipka followed up on his original idea and taught the Tarahumara how to build small household generators from car alternators.
Along with the wind turbine, Wotipka also developed a novel water system for the school building. “There will be stone cisterns built from stone on the site,” he reports. “Usually, rainwater catchment systems have a roof washer. You waste the first few gallons, but you can drink the water. “Instead of just burning off our roof washing water, we use it to flush the toilets. You fill the toilets with an actual nozzle, so you know when you flush that you’re using water. All our water gets recycled. The school is on a mountain, so we built a retaining wall, and then there’s an evaporation bed, and that’s where they’re going to have a soccer field. All the gray water from showers and sinks goes into a vegetable garden and pine nursery.”
As Wotipka explains, “If you reforest with seedlings here, the deer eat them off, and with the harsh dry season and the extreme rainy season, if seedlings are planted young, they die. So we’re building a big nursery. We plant the pine seedlings, the students nurture them till they’re bigger, then transplant them. It will help the kids learn to appreciate the trees.”
Wotipka admires the ingenuity of the people he worked with. “In the U.S., we’re used to a certain way of doing things, but down there, they don’t have access to the standard ways of building. I build out of scrap, but these guys do it for real. Once your tires wear out, they become shoes, and once your shoes wear out, they become door hinges.”
This has led to Wotipka developing views about life in the states. “People in the United States need to open up and stop living in excess. Stop and think about how much we waste. We rely on fossil fuels—why? So we can have our big TV and our SUV, so we can go faster and produce more. When you live on the earth the way the Tarahumara do, it feels so good. You appreciate how slow things go. Your happiness level goes up.”
With that, Wotipka concludes, “People need to slow down. The sun, the wind, the earth—they can give us everything we need. If we need less, we have less stress. The less you need, the happier you can be.” With his ingenuity, he’s helping the Tarahumara live a better life, one he hopes will permeate north of the border someday.
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