Spring 2016
Education Trends

MGE Solar in Schools Partnership

MGE Solar in Schools Partnership

In 2001, MGE donated the largest solar electric systems ever installed on area high schools. A total of 10 Madison-area high schools received solar arrays as part of the MGE Solar in Schools program, a technology-based education partnership that demonstrates how renewable energy can play a significant role in producing clean energy. This generous gift is but one example of how MGE continues its long-standing commitment to support education and renewable energy. In addition to the solar panels, a web-based performance monitoring system was included with each solar array. Monitoring the systems in real time allowed students, teachers, and anyone to track electricity production and the environmental benefits (largely avoided carbon dioxide production) associated with solar electric power. A grant from the Wisconsin Environmental Education Board helped develop a solar curriculum that teachers can use to integrate solar electric science and technology into their curriculum. The electricity produced by the school photovoltaic systems is fed directly into each school and is enough to power about 6.5 homes when all 10 systems are in operation.

The installations included a variety of solar cell technologies including solar roof shingles (at Clark St. Community High School, Middleton), monocrystalline cells (most common), and thin film cells (at Badger Rock Middle School). Not all the systems were installed on school rooftops, primarily to demonstrate how solar electric is not just confined to rooftop-only installations. The Memorial High School array demonstrates how solar panels can be configured into a wall canopy over the front entrance. Some of the systems were intentionally fixed at either 25 or 45 degrees due south to determine which fixed angle would yield the greatest annual electric production in our part of the county. We also documented all costs associated with an array including cell cost, inverter cost (DC to AC electric conversion), fabrication of the racking framework, labor, permits, and engineering site analysis.

Lessons learned

Solar in Schools provides a variety of valuable lessons learned about solar electric performance based on system monitoring. Here's a partial list of things we learned since Solar in Schools started:

  • Fixed solar systems set at 25 degrees due south produce more electricity annually than systems fixed at 45 degrees.
  • The effect of snow cover on solar panels can decrease electric production but also increase reflective gain to enhance electricity output where snow covers immediate nearby surfaces.
  • Cloud cover can reduce solar electric production but not eliminate it.
  • Fixed solar arrays produce about 30% less electricity on an annual basis compared to tracking systems in the same geographical area.
  • For each 1,000 watts of installed solar electric capacity, annual electricity production is about 1,200 kilowatt-hours (kWh). As a comparison, the average residential customer uses about 500 kWh per month. A 3,000-watt solar electric system will produce about 3,600 kWh per year in Madison, Wis.

Curriculum connections

Having solar energy systems installed on a school can help teachers integrate a variety of STEM concepts into the high school curriculum including the science of how solar cells convert electricity into sunlight, various existing and new solar cell technologies, engineering concepts associated with design and site assessments, and of course, math connections to evaluate daily, monthly, seasonal, and life cycle operation. As costs for solar cells decrease and system components become more reliable, evaluating the economics of installing solar systems is a very practical exercise for students to engage in. The Solar in Schools' curriculum provides valuable lesson ideas for teachers. Environmental science, technology education, engineering, chemistry, and earth science are probably the most likely subject areas where solar and other renewable energy topics are studied. MGE has a variety of hands-on learning kits for loan to teachers.

The school building as a learning laboratory

School buildings are an appropriate and convenient location for students to learn about renewable energy systems and school building energy efficiency. Schools have increasingly installed a variety of energy efficient and renewable energy systems in their buildings to reduce operating expenses, dependence on fossil fuels, and reduce carbon emissions. Over the last 20 years, schools have replaced outdated fluorescent lights with LED lighting, installed building energy management systems, incorporated passive design, geothermal heating and cooling technology, and solar hot water systems, all of which contribute to a healthier environment to work and learn. Under current state law, school districts can put forth to their voters special referendums to exceed state spending caps for energy efficiency improvements that ultimately yield valuable long-term energy savings for their communities.