While looking into topics for my ecofriendly product review, I noticed a trend. While sustainable advances allow us to use otherwise unsustainable technologies more sustainably, the ideal the public often associates with them is that because they are more sustainable, they can be used more. Electric cars encourage people to drive more because they have less of an impact than regular gas powered cars. LEDs are so much more efficient than their predecessors that their environmental impact seems almost nonexistent, leading to people using them more frequently and longer than they would have other kinds of lights. I won’t lie, I also definitely have used this mindset before; it’s very easy to fall into. This is further exacerbated by the fact that a lot of comparisons of sustainable products encourages the line of thinking that more efficient products can be used more and for the same cost as their predecessors; for example, the statistic that electric vehicles are 2.6 times more efficient at traveling a mile than gas vehicles can make a consumer come to the conclusion that they can travel 2.6 times more miles in their electric vehicle than their gas vehicle for the same environmental impact.
This is called the direct rebound effect. For example, if a new form of light promised 50% electricity efficiency, but only caused a 20% drop in electricity use, there would be a 60% rebound effect, accounting for the “missing” 30% electricity savings that the new product promised. This “missing” 30% is due to factors such as people leaving lights on longer, or people installing more lights, because they see improvements in efficiency as a way to use the lights more, instead of a way to use the lights the same way as they did, but for less environmental cost.
Many of the sustainability numbers given, like this product is x% more sustainable than y product, assume usage of the two products will be exactly the same. However, when people start seeing sustainable products as a way to do more of something for the same impact, instead of as a way to do something for less impact, the environmental benefit is lessened. While this process rarely, if ever, cancels out the benefits of more sustainable products, it means that their sustainability is never as impactful as advertised. There are five different rebound effect types.
- Super conservation, wherein the savings are larger than expected, and therefore the rebound effect is negative.
- Zero rebound, wherein the actual savings are equal to the savings that were expected, and the rebound effect is zero.
- Partial rebound, where the actual savings are less than expected. The rebound effect is somewhere between zero and one. This is the most common rebound effect.
- Full rebound, wherein the actual resource savings are equal to the increased usage. The rebound effect is one.
- Backfire, wherein the resource savings are negative because usage increased beyond the potential amount of savings. The rebound effect is greater than one.
The first instance of this effect was discovered in 1865 when an English economist William Jevons observed that technological improvements that led to an increased efficiency of coal led to an increased consumption of coal in many industries. He came to the conclusion that technological progress could not be relied upon to reduce fuel consumption; reduced fuel consumption therefore must come through some other means. The fifth rebound effect type, backfire, is also called Jevon’s paradox.
I think this effect is very interesting. Usually, discussions of sustainability focus on the benefits alone of technological innovation. The idea that all innovations lead us to a sustainable future is unquestioned and so no conversation happens about how sustainable products must still be used responsibly in order to actually be eco-friendly.
“Rebound Effect (Conservation).” Wikipedia, Wikimedia Foundation, 4 Feb. 2024, en.wikipedia.org/wiki/Rebound_effect_(conservation).