Sunshine splashing onto school rooftops and campuses across the country is an undertapped resource that could help shrink electricity bills, new research suggests.

The study, published in the April issue of the peer-reviewed journal Environmental Research Letters, shows taking advantage of all viable space for solar panels could allow schools to meet up to 75 percent of their electricity needs and reduce the education sector’s carbon footprint by as much as 28 percent.

At the same time, solar panels could help schools unplug from grids fed by natural gas and coal power plants that produce particulate matter, sulfur dioxide and nitrogen oxides – air pollutants that can contribute to smog and acid rain as well as serious health consequences including heart attacks and reduced lung function. “This is an action we can take that benefits the environment and human health in a real, meaningful way,” said Stanford behavioral scientist Gabrielle Wong-Parodi, an author of the study.

New solar projects may easily slip down the list of priorities in a time of widespread protests by teachers calling for increased school funding, smaller class sizes and higher wages. But the U.S. Department of Energy estimates K-12 school spend more than $6 billion per year on energy, and energy costs in many districts are second only to salaries. In the higher education sector, yearly energy costs add up to more than $14 billion.

The current paper suggests investments in the right solar projects – with the right incentives from states – could free up much-needed money in schools’ budgets. “Schools are paying for electricity anyway,” said Wong-Parodi, an assistant professor of Earth system science at Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). “This is a way, in some cases, that they can reduce their costs. If there’s a rebate or a subsidy, it can happen more quickly.”

Overlooked benefits

Educational institutions account for approximately 11 percent of energy consumption by U.S. buildings and 4 percent of the nation’s carbon emissions. But while the potential for solar panels on homes and businesses has been widely studied, previous research has largely skipped over school buildings.

The new estimates are based on data for 132,592 schools, including more than 99,700 public and 25,700 private K-12 schools, as well as nearly 7,100 colleges and universities. The researchers began by estimating the rooftop area available for solar panels at each institution, the hourly electricity output given the amount of sunshine at the site and the hourly electricity demand of each institution.

Not surprisingly, the study finds three large, sunny states – Texas, California and Florida – have the greatest potential for generating electricity from solar panels on school rooftops, with nearly 90 percent of institutions having at least some roof space suitable for installations. Meanwhile, residents in midwestern states including Wisconsin and Ohio stand to see the biggest reductions in key air pollutants – and costs associated with addressing related health effects – if schools switch from the grid to solar power.

Beyond measurable effects on air pollution and electricity bills, solar installations can also provide new learning opportunities for students. Some schools are already using data from their on-site solar energy systems to help students grapple with fractions, for example, or see firsthand how shifting panel angles can affect power production. “It takes this abstract idea of renewables as something that can reduce greenhouse gas emissions and brings it home,” Wong-Parodi said.