Does more efficient shipping equal more ships and more pollution and emissions? The Jevons Paradox.
By Ryan Skinner (email)
I've had an operation in the new year, and thus more time to read some meaty stuff. I stumbled over a particularly compelling little article in the New Yorker that argued persuasively against the dangers of energy efficiency.
"Em, what?" you may ask. How is energy efficiency dangerous? I'd encourage anyone to consult the full article (a great read) by David Owen directly here. [Sorry, subscription required for full text].
For everyone else, here's the gist. A 19th Century economist named William Stanley Jevons noted that his contemporaries were confusing economic use of fuel (efficiency) with reduced consumption. In fact, the opposite often takes place: Greater efficiency spurs renewed investment and results in even greater consumption. It's become known as the Jevons paradox.
The logic holds. It's similar to an argument I heard about car safety. With all the safe accoutrements that have been added to modern cars, why is traffic mortality still so high? Because people drive faster. If you want real traffic safety, replace the airbag in the steering wheel with a spring-loaded knife. That'll slow people down.
This paradox can be easily seen in shipping. How many times have we heard shipping's wafer-thin champions describe how the per-unit efficiency and cleanliness of ships have radically improved? Of course, any idiot can see that shipping's overall environmental footprint has grown and grown. Cleaner ships begat more ships begat more pollution.
Some would argue that the connection between efficient ships and pollution has become "decoupled". That is, more efficient ships would not trigger increased investment. When energy becomes only a marginal proportion of costs, this happens. So tell me, is energy a marginal proportion of shipping's costs? Will it be any time soon?
A valuable thought experiment in this context might be to consider how great the volume of transport could be given zero costs. That is, if anything could be transported (say, teleported) anywhere, instantly, at zero cost, how much more would be transported than today?
The ultimate irony of some of Jevons' champions is their argument that the best way to cut greenhouse gas emissions would be to mandate unefficient ships. It's counterintuitive, but it at least moves the focus from a slightly misleading metric - efficiency - to the most painful one - cost.
What do you think? Is the game of chasing efficiency counterproductive?