When you think of your average American city, you probably imagine a metropolis of steel and concrete with grimy subway tunnels, blaring taxicabs, and sleek glass walls. However, if you took a moment to look up toward the rooftops, you might spot the future.
Popularized in urban areas, but spreading to the rest of the world, green roofs are the future of agriculture and clean energy, and they are exactly what they sound like. It is possible, and beneficial, to build a garden into your roof. In fact, they have been used for 4,000 years.
In ancient Babylon, they were built to prevent water damage and to keep the roofs from falling in. As technology has advanced, other benefits have come to light. An abundance of green roofs in an area can cool the surrounding temperatures significantly and reduce the sulfur dioxide and nitrous oxide in the air, improving the air quality. But, even on a smaller scale, green roofs can expand the lifespan of a building and reduce maintenance costs.
For example, Danville Area High School’s annual electricity bill is about $123,644. On average, installing a green roof will reduce building energy use by 0.7 percent, which leads to 23 cents saved per square feet of roof, annually. If, hypothetically, the high school were to install a green roof that covered every inch of the roof’s surface area, the bill could be reduced by $25,300 annually. And, these savings would mean that the roof would pay for itself in about 60 years.
Of course, green roofs are much more likely to be worth the initial investment in urban areas, where green space is limited. Nevertheless, it is a technology that is well worth keeping an eye on. As global warming becomes more dangerous and the world’s population continues to increase as it is, green technology, such as these roofs, is becoming increasingly important.
Jill Nied is an AP Environment student at Danville Area High School. Students/teachers interested in submitting articles for publication in The Danville News should email firstname.lastname@example.org.