
Exit signs are so ubiquitous that they're almost invisible. Every public building has them. In fact, they are so common that, taken together, these little signs consume a surprisingly large amount of energy.
Each one uses relatively little electricity, but they are on all the time. And we have a lot of them in our schools, factories, and office buildings. The U.S. Environmental Protection Agency estimates that there are more than 100 million exit signs in use today in the U.S., consuming 30–35 billion kilowatt-hours (kWh) of electricity annually.
That’s the output of five or six 1,000 MW power plants, and it costs us $2-3 billion per year. Individual buildings may have thousands of exit signs in operation.
To put this into a bigger context: This is just one small part of what makes buildings, in general, incredibly energy intense. In the United States, we use more energy powering our buildings—from the lights, to the heating, to the stuff we plug into the walls—than we use to do anything else. Because of that (and because of the fact that electricity is mostly made by burning coal or natural gas) buildings produce more greenhouse gas emissions than cars.
Read more about the energy consumption of exit signs and how we can use less energy, while still getting the same services, at Green Building Advisor
Take a look at some stats on energy use in buildings at the Architecture 2030 website
Via Jess McCabe
Image: Exit Sign, a Creative Commons Attribution (2.0) image from mtellin's photostream
First discovered a year ago, Oumuamua is the strange cigar-shaped object of interstellar origin that flew through our solar system at 196,000 mph. Since it was first spotted, scientists haven’t decisively determined whether it’s a mildly active comet or something else. Now, astronomers Shmuel Bialy and Abraham Loeb of the Harvard Smithsonian Center for Astrophysics […]
In Towards Construction Based Data Hiding: From Secrets to Fingerprint Images , published in IEEE Transactions on Image Processing (Sci-Hub Mirror), two Fudan University computer scientists propose a fascinating method for hiding encrypted messages in fake fingerprints that are both visually and computationally difficult to distinguish from real ones, which could theoretically allow the use […]
In September, a consortium of 11 of Europe's largest science funders announced, "Plan S," whereby they would no longer fund research unless the grantees promised that the results would be published in an open access journal, which anyone could read and copy for free. Two more funders quickly signed up after the announcements, bringing the […]
Even on outdated models, smartphones have imaging technology that puts the compact cameras of just a decade ago to shame. If you really care about the pictures you take, stop treating your smartphone camera like just another app. It can shoot cinema-quality video and photos with the right tools, and the Rigiet Smartphone Gimbal might […]
Slithering along like its namesake, Python has woven itself into nearly every aspect of web development since its inception the late ’80s. Flexible and readable, the possibilities of this programming language are nearly limitless – with the right understanding. And the quickest way to that understanding is the Ultimate Python Programmer’s Bootcamp Bundle. This comprehensive […]
Starting a podcast is easier than ever — just scroll through the variety of voices that are out there today. Getting your podcast heard? That’s a whole other level of expertise. Luckily, those trade secrets are fair game for all in the Podcasting 101 Bundle. Before you hit record, do yourself a favor and hit […]