New Methodology: SOLAR PANEL POWER IN SCHOOLS
DRESSED IN PASTEL pink and green for an early spring day, second grade student Katherine Cribbs was learning about energy on a virtual field trip to her own school.
With a flurry of touchscreen taps, she explored the âenergy dashboardâ of Discovery Elementary in Arlington, Virginia. On her tablet, she swiped through 360-degree views of her school, inside and out. She clicked on icons embedded in the virtual classroom to learn about energy-saving features such as LED lights and super-insulated exterior walls made of concrete-filled foam blocks.
Exploring the virtual school kitchen, she could read about how the lack of a deep fryer means less energy is needed for venting grease from the air. Another swipe whisked her up to the schoolâs roof, where about 1,700 solar panels spread out before her.
After a few minutes, she looked up from her computer to explain her progress in a confident voice that rose above the second-grade din. âI learned that our solar panels rotate,â she said. âSo, wherever the sun moves, the panels go, too.â
In addition to this virtual tour, Discoveryâs dashboard displays, in real time, the schoolâs energy generation. And in colourful bar graphs and pie charts, it also tracks energy use broken down by lighting, plug load, kitchen, and HVAC. The tally reveals that Discovery generates more energy through its solar array than it uses over the course of the year.
Dozens of these ultra-green schools are going up in every sort of districts such as urban and rural, affluent and lower income, blue state and red state. Much of the advocacy for net-zero buildings has focused on environmental and economic incentives. K-12 schools run up a $6 billion annual energy tab every year, the Department of Energy reports more than they spend on textbooks and computers combined, and second only to the cost of teacher salaries. But the K-12 schools leading the net-zero charge are uncovering major educational benefits as well.
WHILE DISCOVERYâS SECOND-GRADERS scoured their school for light and heat energy, a group of third graders huddled around a table to brainstorm fraction âstory problemsâ using the schoolâs energy data.
They suggested using fractions to find out how much of yesterdayâs solar energy was used up by the school, to compare one hourâs solar energy to the whole day, and to show how much of the schoolâs energy use was from lighting. Their numerators and denominators could come from the dashboard.
âEverywhere you walk through this building, you can learn from it,â said Discoveryâs principal, Erin Russo. Thereâs a large screen energy dashboard by the schoolâs main entrance, and the buildingâs mechanical systems, including the geothermal pumps and the solar inverters that change direct current to alternating current, are prominently displayed behind large glass windows in the hallway.
Learning about the behaviour of light, Discoveryâs fifth graders have visited the schools rooftop solar lab (a handful of adjustable panels that are metered separately) to see how angling the panels changes their power production.âEnergy is normally so invisible,â said a fifth-grade science teacher, Andrew Bridges.
âBut the kids can see these solar panels right outside their window. They can see the energy production dipping on cloudy days.â