A small Wisconsin village installs a pair of wind turbines at its treatment plant that could make electricity a source of revenue, rather than an expense
Anyone would rather receive a check than a bill from the power company every month. That is a real possibility for the Village of Cascade, Wis., about 15 miles west of Lake Michigan.
Coasting down the long hill to downtown, you’d have to know exactly where to look to see two wind turbines that have made the Cascade wastewater treatment plant the first in the state to be 100 percent powered by wind energy.
The 130,000 gpd aerated natural pond treatment plant serves about 700 customers in and around the village. The two 100 kW wind turbines installed this year will save the community $30,000 a year in electrical costs. That’s nearly 10 percent savings in the village’s annual budget of $330,000. With an expected lifespan of 30 years, and with utility power rates expected to escalate, the turbines could save more than $1 million.
Being the first wind-powered treatment plant in the state is a source of pride, according to village trustee Joe Harrison, but it also makes financial sense. “We’ll get our money back in twelve-and-a-half years, and that’s at current electricity costs,” he says.
The village invested $504,000 toward the total cost of $904,000. The rest came from Wisconsin Focus on Energy ($250,000) and the local utility, WE Energies ($150,000). The village’s share of the cost is being funded through the savings, from selling excess power to WE Energies through the utility’s net metering program, and from future energy credit revenues.
None of the cost was borne by taxpayers, and there was no sewer fee increase. While residents in some nearby towns pay up to $200 a month for sewer and water, Harrison pays about $180 for three months for his 3,300-square-foot home and business.
The turbines, from Northern Power Systems in Vermont, went online in June 2010. Standing 120 feet high, the gearless Northern Power 100 turbines are designed for remote and isolated sites with lower wind speeds. It took just 13 hours for Kettle View Renewable Energy of nearby Random Lake to install the turbines.
The Northern Power website includes real-time monitors of several of its installations, including data on cost savings and emission reductions. It also offers renewable energy educational programs for schools. System owners have access to real-time monitoring and historical reports.
Cascade spent two years, with help from Focus on Energy and the village engineering firm, Strategic Municipal Services, looking at ways to power the treatment plant completely with renewable energy. Biogas was the first idea eliminated, simply because the plant doesn’t create enough methane.
Harrison says solar was 50 percent more expensive than wind, would take up four of the plant’s 9.5 acres, and would meet only 80 percent of the electrical need. With an average wind speed of 12.4 mph at the plant, the two wind turbines are forecast to generate about 110 percent of plant demand, an expected 295,000 kWh per year.
“It just seemed to us that wind power was going to supply the best bang for our buck,” says Harrison. “It’s a totally green setup. If there’s a breeze, they’re producing pennies. With higher winds, they’re producing nickels.” The turbines will also prevent the emission of nearly 400,000 pounds of carbon every year.
The plant’s lagoon and treatment systems were also upgraded in 2010. The $1.4 million project replaced the three existing lagoons with a 1.2-acre covered lagoon to meet new ammonia standards. With better temperature control to improve bacterial treatment, the wastewater will be returned to the north branch of the Milwaukee River in about three weeks rather than 45 days.
The upgrade went online last October with a new clarifier; high-efficiency pumps, blowers and other equipment; and an Eaton motor control system. The higher efficiency will help increase the amount of electricity sold back to the utility.
In addition, UV disinfection replaced chlorine, cutting chemical costs. That work was funded by a 2.5 percent loan from the state’s Clean Water Fund.
The two wind turbines may not be the end of renewable energy for the village. “There is interest in solar power for the village hall and garage,” Harrison says.