In one 50-minute period last month, the Intro to Engineering students at Chatfield High School in Jefferson County, Colorado, charted the strength of solar panels at their desks, then climbed through a trap door to examine the 100-kilowatt solar array on their school’s flat roof.
“You see a couple of panels that have been shattered by last year’s wind storm,” teacher Joel Bertelsen told the 32 students, who were peering intently at the panels when not testing the springiness of the roof. “It hasn’t affected the efficiency of the system much so far.”
As more and more schools install solar panels on roofs, more and more students inside are getting a wide spectrum of knowledge about solar energy — thanks in part to the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL).
Jeffco Public Schools is Colorado’s largest school district, with (nearly) 86,000 students and 154 schools — and it sprawls from the plains to high mountain peaks.
Thirty of its schools have rooftop solar panels. Golden Power Partners collaborated with Renewable Social Benefit Funds (RSB Funds) for financing, using combined federal and state incentives as well as Xcel Energy renewable energy rebates, and Tecta America for construction.
Jeffco Public Schools paid no upfront costs, and the “Solar on Schools” project is expected to save Jefferson County taxpayers $2.88 million in energy costs over the next 20 years. RSB Funds will own and maintain the solar panels, and it will sell the electricity the panels produce to the district at a price below its current utility rate.
To further amplify its green credentials, the school district two years ago called for proposals to bring solar into the classroom.
“We worked with Golden Power Partners to incorporate a user-friendly data acquisition system that the teachers and students could use in the classroom to get live data about their solar systems,” Linda Lung, manager of education programs at NREL, said.
Golden Power Partners and NREL chose DECK Monitoring to set up a system that allows the students to see how their solar panels are working at the very moment, that day, that week, that month, or that year. And the students can compare how fast their school is turning photons into electrons compared to a school 30 miles away.
“And in Jefferson County, that can mean vastly different weather,” Lung said. “There could be a blizzard in Evergreen in the mountains, while the sun is shining in Arvada — or vice versa, for that matter.”
Students are having great fun finding out how weather can affect the panels’ performance.
Live Data Bolsters Intensive Solar Curriculum
To ensure that the students get first-rate knowledge about solar energy, NREL used the $30,000 awarded to the winning proposal to organize spring and summer Energy Institute for Teachers workshops attended by the most interested math and science teacher from each of the 30 solar-powered schools — which include elementary, middle, and high schools.
“NREL worked with Jeffco staff to integrate standards-based renewable energy lessons with the data monitoring system so teachers could incorporate the actual real-time data into science and math classes. The photovoltaic system becomes a learning laboratory and an exciting learning tool — plus the school benefits from all the clean, renewable electricity it produces,” Lung said. So a sixth-grade math teacher might have students graph differences in peak performances or changes brought on by cloudy days.
Bertelsen attended NREL’s spring workshop and wasted little time incorporating solar into his Intro to Engineering class, which is comprised of seniors with their eyes on two-year or four-year colleges.
Experimentation Leads to Deductive Reasoning
On a recent day, Bertelsen’s students were using meters to gauge the changes in volts and amps as artificial light moved farther away from the CD-case-sized solar wafers at their desks.
“So at 3 inches, we’re at 5 volts,” Chatfield senior Sebastian Goff said. “Let’s check it at 6 inches.”
After a few more measurements, a few hot fingers, and a few false starts, the pattern was clear:
“There’s a direct relationship with the amps,” Hoff said. “Twice the distance means half the amps.”