Is an equivalency enough?
Wednesday, August 4th, 2010The equivalency is a common device used in sustainability communications. You’ve seen it. It usually goes something like: “The emissions we reduce by [insert environmentally responsible action here] are equal to taking 500,000 cars off the road for a year. Or like this: By [insert recycling activity here] we save the equivalent of 20,000 trees.
Many of the equivalencies you see in sustainability communications come from calculations provided by the U.S. Environmental Protection Agency’s handy greenhouse gas equivalencies calculator, which helps express carbon emissions in terms of passenger vehicles on the road, barrels of oil consumed, railcars of coal or even propane cylinders used for home barbecues.
The EPA’s website says the calculator can help you translate “abstract measurements into concrete terms you can understand.” But does it? Without context, I have no way of understanding what removing 500,000 cars from the road really means. The comparison gives me a concrete image, but the idea is still abstract. Expressing it as a percentage of all the cars on the road might be more meaningful, but we all know that number wouldn’t sound as impressive as 500,000.
So, what’s a writer to do? I want to suggest we find more relatable ways to express these ideas, but maintaining accuracy can be tricky. So, here’s a thought: We could use equivalencies to make a larger point.
For example, as we gathered data for our own sustainability report, we learned that by setting two-sided printing as our default, we saved the equivalent of two trees in one quarter alone. That fact doesn’t mean a lot on its own. But, it helped support a larger idea we wanted to communicate. If every small business our size in the U.S. did the same thing, together we could saved 385,264 trees in a year. The imagery is still abstract, but it gives us a compelling way to encourage other businesses like ours to make small changes that add up to a bigger difference.
What about you? How do you use equivalencies in your sustainability communications?








