What once was an expensive investment that returned little to consumers is now providing a way for American schools to divert energy costs into educational resources.

According to the Solar Energy Industries Association (SEIA) solar capacity at K-12 school has nearly doubled in the last three years, giving schools more funding for teachers and educational resources such as technology or new tools.

“Solar can help school districts save millions on electricity bills, freeing up funds for additional teachers, improved facilities, and enhanced academic and extracarricular programs,” said Andrew Luecke, present and executive director of The Solar Foundation. “It can also serve as hands-on STEM laboratories for students to learn about clean energy from the sun.”

There are now 5,489 K-12 schools in the US that use solar energy according to a report by The Solar Foundation, Generation 180, and the SEIA.

Solar installation rates can be attributed to decking installation costs with the average price of a solar school installation dropping nearly 67 percent in the last 10 years, and 19 percent in 2016.

In 2017, nearly 4 million students attended schools with solar power, with a combined capacity of 910 megawatts (mw), an 86 percent increase from 2014.

The amount of electricity these schools produce annually is enough to power 190,000 homes.

California leads the nation in the number of solar schools by state, with 1,946 solar schools and a 489 MW capacity. New Jersey, Arizona, Massachusetts, and New York are also leading states following California.

Nevada has the highest adoption rate, with 23 percent of of schools using solar energy statewide and Arizona has the most solar school capacity on a per capita basis, at 86 watts per student.

Schools also have more financing options that minimize up-front investment.

Recently, most schools have financed their solar installations through power purchase agreements (PPAs), in which a third part finances, builds, owns, and maintains the system. This allows the schools and districts to purchase solar with very little initial cost.

In the last three years, more than 90 percent of schools used PPA to install solar.

“There is a reason solar is spreading so quickly across America’s school districts...when schools go solar, the entire community benefits,” said Abigail Ross Hopper, president of SEIA. “By switching to solar energy, schools immediately see their electricity bills go down, leaving more money for learning.”