Drones, crops and Jevons' Paradox

Monday, August 22, 2016
by Cameron Shelley

Jevons' Paradox concerns how increases in efficiency can lead to increases—rather than decreases—in consumption of resources.  Designers expend a great deal of brainpower and passion on increasing the efficiency of their designs.  The goal is often to decrease consumption of a resource, as a way of improving overall sustainability.  In brief, the reasoning is that if a given task can be completed with fewer resources, then those resources will be conserved.

British economist William Stanley Jevons argued that the reverse will happen.  In a nutshell, he argued that by making consumption of some resource more efficient, the cost of consuming that resource would decrease, thus stimulating consumption of it.  That is, consumption would go up.  That is Jevons' Paradox.

When reading about how some new technology will increase the efficiency of something, and thus its sustainability, it is interesting to consider how Jevons' Paradox may arise and, perhaps, spoil the party.

It was in that light that I read an article about how commercial drones will increase the efficiency of agriculture.  For example:

Felix Weber is a crop consultant who operates Ag Business & Crop in Palmerston, Ont., in Wellington County. He says images collected from UAV flights can save a farmer money and help reduce chemicals going into the soil.

He gives an example of wheat damaged over the winter. Rather than adding nitrogen to the entire field in trying to save the wheat, UAV analysis suggested targeting only certain areas of the field. That saved money and was more environmentally friendly.

"My recommendation was not to apply nitrogen where there wasn't enough wheat. That was a cost savings to the farmer and 80 per cent of nitrogen was added rather than 100 per cent."

In short, farmers can use drones to reduce the amount of pesticide and other stuff sprayed onto crops in order to achieve a given yield.  That will reduce costs and the pollution load on the environment, both wins for sustainability.  Also, the cost of food for consumers should then be reduced.

Jevons' Paradox would suggest that both pesticide and food consumption should rise as a result of this application of drones.  How could that be?

If we assume that demand for farmland and food is fixed, then it is hard to see a problem.  However, the point of the Paradox is that demand can be stimulated by increases in productivity of supply.  

In the case of farmland, the ability to produce a bushel of wheat, say, at a lower cost could stimulate increases in the production of wheat.  That might be accomplished by converting non-wheat acreage to wheat or by increasing the productivity of each acre already used to produce wheat.  This might also stimulate the conversion of marginal land, e.g., forests, into farmland for wheat growing.  Those new crops would need to be sprayed, thus driving an increase in the amount of pesticide applied to crops over the whole agricultural system.

In the case of food, the availability of cheaper food might stimulate consumption of it.  Homer Simpson once said that he discovered a new meal between breakfast and brunch (brunchfest?).  People, especially people with money, are very good at inventing new ways to eat or waste food.  Who's to say that we won't find even more, especially when food prices decrease?

I do not know if adoption of drones in agriculture will have these effects.  The agricultural system is too complex to warrant sweeping conclusions from a few musings.  However, it is instructive to remember that the so-called efficiency strategy for increasing sustainability is not a slam dunk either.