A fascinating survey of people asked them about the perceived energy savings from a range of environmental behaviors (turning off lights, driving a more fuel efficient car, using energy saving appliances, etc.), and compared their answers to the actual energy savings of those same behaviors. One main takeaway from an online report about the survey is that people don’t know much about what saves energy. That’s sort of true, but not quite. As the authors of study (ungated here) write:
For a sample of 15 activities, participants underestimated energy use and savings by a factor of 2.8 on average, with small overestimates for low-energy activities and large underestimates for high-energy activities.
Why did they make these estimation mistakes? Why did they consistently not know that actions like tuning up a car twice a year produces a much bigger conservation impact than driving 60 mph instead of 70 mph for one hour? One answer is anchoring. The study’s survey offered respondents the reference point of an incandescent light bulb, which was described as using 100 units of energy over a one hour period. From there, respondents adjusted upward for other behaviors and appliances, knowing they used more energy, but not knowing how much more.
The authors argue that the incandescent bulb is a common reference point for most people today. That sounds fair. The broader lesson is this: If you’re like most people you don’t know a lot about how much energy various behaviors and appliances use. You do have a reference point, though, probably related to some action or appliance you use commonly and may have read something about. Whatever that action is, it’s probably affecting your ideas for reducing your energy usage, albeit not as much as you think.