Monday, November 9, 2009

Peterson/Stewart Home


Owners: Jeff Peterson & Nancy Stewart
Location: 750 Round Lake Rd., Luck, WI 54853
Phone: 715-472-2728
Email: peterson [at] lakeland.ws
Installer: Legacy Solar
Installed: April, 2009
Components: 8 Sharp 187-watt PV modules, Fronius inverter

This grid-tied photovoltaic system is rated at 1.5 kW, though output has at times surpassed that level. The array is fixed in orientation at 10 degrees west of true south to provide optimum output during times of peak system load. Angle from horizontal is adjustable to account for seasonal variations in the sun's position in the sky. Owners make those adjustments themselves four times a year.

Maximum daily output is 10 kW hours -- greater than homeowners' normal consumption. Polk-Burnett Electric Cooperative (PBEC) provides net metering, so excess production is compensated at the retail rate. Expectation is for this system to provide about 40% of electric needs over the course of a year. Electric bills, formerly $70-$80 per month, have been reduced by $20-$25 per month.

Total installed system cost was approximately $15,000. A 20% incentive from PBEC and anticipated federal tax credits of 30% effectively cut that cost in half. Still, payback at current electric rates is 20+ years. This will, of course, be shortened any time electric rates increase.

Photo: Mounting pole set in rebar-reinforced concrete capable of withstanding 100 m.p.h. winds.

Photo: Installer Kris Schmid attaching ground wires.

Photo: Lightning arresters, inverter, circuit breaker inside garage.

Photo: Display shows current production in watts per hour.

Photo: New meter under old measures outgoing kilowatts. Monthly credit from PBEC is based on difference between top reading (incoming) and bottom reading.

Photo: Manual disconnect on garage exterior provides redundancy to protect line workers.

Photo: Installation crew: Dan Perkins, Kris Schmid, Dave Jacoby. More photos of installation process are available here.

Photo: Visitors always welcome!

Sunday, November 8, 2009

Osceola Middle School


Location: 330 Middle School Dr., Osceola, WI 54020
Contact: Bob Schmidt, Buildings & Grounds Director
Email: schmidtb [at] osceola.k12.wi.us
Phone: 715-294-4140
Designer: Energy Concepts, Hudson, WI
Installer: Steiner Plumbing & Heating, River Falls, WI
Components: 32 - 4' X 10' SolarSkies collectors; drain-down system
Installed: August, 2008

The following article appeared in the Winter 2009 issue of The Renewable Quarterly, a publication of RENEW Wisconsin, a nonprofit advocacy group based in Madison, WI:

Solar-Heated Pools Pass the Test at Osceola Middle School
by Michael Vickerman

If you're wondering whether a solar hot water system can also be an effective teaching tool for students and community residents alike, look no further than the Osceola Middle School.

Since it went on-line in August 2008, Osceola's solar installation has been doing double duty, quietly heating three indoor pools -- a community spa, a wading area, and a competition pool -- and the building's domestic water while demonstrating to schoolchildren how renewable energy can be captured and put to productive use.

For school leaders, the project was as much about educating Osceola residents young and old as it was an investment in lower operating costs.

Photo: Members of Polk County's Renewable Energy Committee meet with Osceola school officials.

"This is about being a leader in our community," says Bob Schmidt, who heads the maintenance operations at the middle school. "If we want to walk the talk with young people, we need to be out in front and show the way to the future. There is a lot of teaching potential in having solar panels on the roof."

"We have to prepare our students for a renewable energy future, because that's where the jobs of tomorrow will be found," adds Schmidt.

Photo: This real-time display is accessible by students as they monitor the system's performance.

Perched above the school entrance, the solar arrays are impossible to miss. As they walk into the school, the students are reminded that their school is harvesting the sun's radiant energy every day.

While in science class, students can track how much heat the system can capture and deliver on a sunny day and compare that to its output on an overcast day. The sophisticated monitoring system archives time and temperature data in 15-minute intervals, allowing future science classes to draw comparisons with real-time data. Indeed, if ever a solar energy system came with its own lesson plan, this is the one.

Photo: Bob Schmidt (third from left) explains the the mechanics of the system.

For the school district, the installation's educational value is equaled by its estimated impact on its bottom line. With the aid of a $46,000 award from Focus on Energy, Osceola's $170,000 investment in solar energy should be fully recouped in 10 years. From that point onward, the installation will begin saving taxpayer money while helping sustain a highly valued recreational activity for the 2,700 residents in this northwestern Wisconsin village, especially during the long winters.

Each year Osceola's solar thermal system should offset the consumption of 3,612 therms of natural gas that would otherwise heat the 200,000 gallons of pool water inside the building.

Schmidt and other officials from the school researched projects at schools around Wisconsin before deciding on a proposal by a renewable energy engineering firm, Energy Concepts (ECI) in nearby Hudson. ECI's Craig Tarr, a licensed Professional Engineer, has been working in building and facility engineering for two decades. He is now using this background to merge renewable energy into specialized solar and wind applications for large-scale public and commercial buildings.

Photo: This thermal pool blanket saves energy, water, and reduces the need for chemicals previously lost to evaporation.

Of the many features that Tarr custom-designed for this installation, he is proudest of the controls package that allows each of the pools to be solar-heated at different temperatures. The system is configured to allow the solar heated fluid to transfer heat, in series, to the pool that needs the most heat.

An investment like this usually prompts customers to think of new ways to reduce fossil fuel use. District officials are weighing a more ambitious renewable energy initiative that will involve the other four buildings in Osceola's educational campus. Whatever direction the school district settles on, it can count on Focus on Energy to provide it with technical, financial and project facilitation support.