Turbines Stand Tall

Wind energy and creative thinking help a small town in Wyoming reduceoperating costs for a new treatment system and limit rate increases
Turbines Stand Tall
Four tandem wind turbines provide renewable power for Medicine Bow’s water treatment plant.

Interested in Energy?

Get Energy articles, news and videos right in your inbox! Sign up now.

Energy + Get Alerts

The small Town of Medicine Bow, Wyo., is tucked between mountain ranges in uranium-rich land, posing water quality problems that are energy-intensive and costly to treat.

Using wind turbines for supplemental power, the community saves up to 30 percent on electricity for water treatment. In 2011, the U.S. EPA recognized the town for using renewable energy, making it an example of what communities can do to make water operations more sustainable. Medicine Bow became the first town to win the EPA Clean Water State Revolving Fund PISCES award and the Drinking Water State Revolving Fund award in a single year.

 

Tougher regulations

In the 1970s and 1980s, Medicine Bow was a prosperous mining town with a population of 1,100. However, when nearby uranium and coal mines closed in 1982, the local economy sank, and the population dropped to about 270, where it has remained.

The same uranium that once made the town thrive eventually became a problem for the drinking water supply. In 1989, the state government required Medicine Bow to reduce the uranium and radium levels in its drinking water. Previously, the town needed only chlorination for treatment.

“We could have dug the wells deeper for more water production, but we might have gotten into other contaminants, so we decided that the best way to deal with the problem was to treat it,” says Charlie George, director of public works and one of two Level 2 water treatment operators on staff.

 

New treatment process

In 2004, a new water plant went online to treat up to 316,000 gpd drawn from three wells eight miles east of town. The main source is an artesian aquifer that flows at 600 gpm and pulls from the Casper-Tensleep basin. Water travels to the plant via a 12-inch pipeline with help from four lift stations.

The plant uses a cation exchange treatment system to remove uranium and radium. To begin treatment, the intake water flows into a filter containing positively charged ion resins. The uranium and radium attach to the resins. A backwash system periodically cleanses the media using a heavy salt brine solution, which also recharges the resins.

The discharge goes to an evaporation lagoon, and the clean water goes to a 1.5-million-gallon storage tank before distribution to the town’s 168 active water taps. “It’s a very expensive but very effective treatment plant,” George says.

When the plant was built, the recommendation was to increase residents’ water bills by up to 75 percent. Such an increase would have been difficult for the many households with unemployed and retired people with incomes averaging below $30,000.

Seeing the town falling into debt from water treatment expenses, yet wanting to avoid rate increases, George looked for a creative solution. “Raising rates on someone on a fixed income, even a couple dollars per month, can be very hard on them,” George says. “We are in constant battle to figure out how we can continue to support water treatment without having a $100-per-month water bill. The municipality is responsible to have open minds and forward thinking to find ways other than raising rates.”

To help offset costs, George looked to alternative energy and found wind power as a feasible option. Nearby wind farms operated by a private company had proven successful and set an example for Medicine Bow.

 

Turning to the wind

George consulted with renewable energy company Sunpower Energy to find a wind power solution that would comply with Wyoming’s net metering law, which allows nonutility generators to supply up to 25 kW. Sunpower recommended installing nine Skystream 3.7 wind turbines rated at 2.4 kW each.

Medicine Bow applied for a grant from the American Recovery and Reinvestment Act (ARRA) and was awarded $110,000 in June 2009 to cover the entire project. Within two months, the turbines were erected, online and running at full capacity.

Four turbines stand next to the lift stations, four turbines are in tandem outside the treatment plant, and one is outside the maintenance building. Medicine Bow became the first town in Carbon County to partner with the local utility, High Plains Power, to connect wind turbines to the grid. Whenever the power generated by the turbines exceeds the treatment system demand, the excess is fed to the grid. High Plains Power gives Medicine Bow a quarterly rebate on expenses for all net power the turbines add to the grid.

“Our plant doesn’t run 24/7, and our lift stations only run a couple of minutes every couple hours, so 22 hours per day the turbines are producing power to put back into the grid,” George says. “It allows us to see a savings of 25 to 30 percent per year on electricity. That’s big savings for a small town like us.”

The 35-foot-tall turbines have a 5-year warranty, and maintenance is handled by Range Solar and Wind. The turbines are quiet (89 decibels at 18 feet) and are located more than 120 feet from any residence, so initial concerns about noise were resolved.

 

Future improvements

Medicine Bow town engineer Derek Johnson of Sunrise Engineering is looking to save even more energy by improving treatment plant lighting and heating systems. Also under investigation are treatment options that use less salt in the brine and need less backwashing. The 18 hp backwashing pumps are the biggest power users in the cation exchange process.

The turbines’ life expectancy is 25 years, and George hopes replacement funding will be available by then. Medicine Bow expects its population to increase by 500 percent or more if a proposed coal-to-gasoline plant is built nearby in summer 2012. At least 1,500 workers could flood the community during construction, posing new challenges for the water treatment system. However, more residents also would provide more revenue.

For now, savings from the wind turbines allow Medicine Bow to keep rate increases at a minimum, making it easier for George and his staff to work with residents in a close-knit community. “Everyone knows one another and you have to try to work with them and their problems,” George says. “The bigger cities can turn water on and off, but the people don’t know the guy who’s doing it. When you turn off somebody’s water here, you know who they are and you know the problems they are facing.”



Discussion

Comments on this site are submitted by users and are not endorsed by nor do they reflect the views or opinions of COLE Publishing, Inc. Comments are moderated before being posted.