Many school systems have educational programs on energy conservation, recycling and becoming more green. Kids come home full of excitement and try to get their parents to do their part. Does the school itself lead by example? A tour through many educational facilities often finds the opposite. Schools continue to add information technology equipment, often into an aging electrical infrastructure. In difficult economic times with escalating energy costs and pressure to reduce expenses, how often are the lights turned out when a room is vacated? According to Energy Star, it costs $6 billion to power America’s primary and secondary schools, more than is spent on textbooks and computers combined.
Although I could not find specific data on how energy is used in educational facilities, the profile is similar to commercial buildings. According to the U.S. Department of Energy, commercial buildings, defined as service-providing facilities and equipment (businesses, government, other institutions), have the following energy consumption breakdown:
• 25 percent lighting
• 13 percent heating
• 11 percent cooling
• 6 percent refrigerating
• 6 percent water heating
• 6 percent ventilating
• 6 percent electronics
Geographic location has a significant impact on cooling versus heating percentages, but starting from the top, lighting is the largest category. How many school districts have ongoing replacement programs for more energy-efficient luminaires, motion sensors in locations not normally occupied but where lights are prone to being left on, photocells to reduce interior lighting when exterior lighting is adequate, or even cleaning of light fixtures to make better use of the output being provided? How many schools have conducted baseline energy audits and can account for where and how efficiently energy is being used?
There are more than 1,300 Energy Star-labeled schools in the United States, but that is just 1 percent. In 2004, Florida schools became the first in the nation to use the “Utility Report Card,” providing a Web-based system, which tracks, evaluates and charts energy consumption in several districts. Spencer Abraham, U.S. Secretary of Energy in 2004, said there are multiple rewards to such a system.
“[T]he ability to pinpoint energy use in our nation’s schools will give school districts a tool to assess where they can save energy and save money. Not only will energy be saved, the students will have the opportunity to learn more about the cost of energy and smart energy use,” he said.
Yet, data on the Web site reveals electrical energy consumption has increased 10–20 percent in most of the districts reporting, since the program was initiated. Kilowatt-hours have gone up to around 8 kWh per day per student in several of the districts, and not just in the summertime when the air conditioning load would be peaking. Since schools operate for about half the waking hours of a typical person per day, there is the potential for a significant reduction to the overall electrical consumption picture without compromising the quality of the educational process if the same energy-conservation programs used in commercial and industrial facilities are applied to schools.
The area of renewable energy is another opportunity to teach by example. Many schools in areas with high air conditioning loads are located where the solar energy potential is Zone 3 or higher, generally considered a good site for photovoltaic-produced electricity. Elementary or primary schools are often single-story buildings, which means there is more roof space per square foot of the building than multistory commercial buildings. Using a 10W-per-square-foot solar panel covering on the roof of a 20-by-40-foot classroom would produce 8 kW peak or, using the 50 percent rule of thumb over the course of the day, 4 kW average. Over the 10 hours of usable light, that would yield 40 kWh per classroom per day. If one assumes 20 students per classroom, then this would be 2 kWh per student, about one quarter of the electricity used per student in the aforementioned example. In addition, the panels would shield the roof from direct sunlight, reducing the heating effect on the roof, which would further reduce the air conditioning load.
Sure, there are a lot of issues. There would have to be a significant capital expenditure while budgets are being tightened. But when energy consumption continues to go up and energy costs rise even faster, solutions need to be explored. Not only can students learn about the subject, they see it in action. We might be inspiring the next generation of architects and engineers who would develop even more affordable sources of renewable energy for designs of net-sum zero-energy school buildings.
BINGHAM, a contributing editor for power quality, can be reached at 732.287.3680.