Jevons’ paradox: what it is, why it occurs, and examples

Let's see what Jevons' paradox is, a curious phenomenon that occurs in many aspects of life.

There is a widespread belief that the more efficient something is, the less it is used because it does not require as much time and resources to be devoted to it each time it is used compared to previous versions of the same product or service.

Although common sense would convince us that this is the case, it seems that the reality is quite different. When something is improved, it ends up being used even more.

This maxim is the one defended by the Jevons paradoxa phenomenon that, although conceptualized more than a century and a half ago, can be observed in countless situations. Let's take a closer look at what it consists of.

What is Jevons' paradox?

In economics, the Jevons paradox occurs when a situation occurs in which technological progress or the application of a government policy increases the efficiency of a given resource, thereby reducing the cost associated with its consumption, but the rate of consumption of that same resource increases considerably, due to the fact that the demand for that resource also increases..

This clashes with the belief that, if something becomes more efficient, its use will be reduced because since it works better it requires less use.

We owe this idea to the English economist William Stanley Jevonswho, in the mid-19th century, observed that technological improvements that had increased efficiency in the use of coal had brought as a rebound effect an increase in the consumption of this resource, which was increasingly used in more and more factories. This economist argued that, contrary to what common sense and intuition might suggest, economic progress does not necessarily imply a reduction in the consumption of its resources as a whole.

Despite being a nineteenth-century idea, Jevons' paradox has been re-examined in modern times by economists interested in how improvements in a given technology or in the use of a resource bring with them a notorious rebound effect in the form of increased consumption.

In fact, this paradox can be seen today in many aspects of modern life, manifesting itself in things that seemingly seem so little different.It manifests itself in such seemingly unrelated things as the number of roads, energy-saving light bulbs or low-calorie foods, examples that we will explain in more detail a few paragraphs later.

History of this concept

The Jevons paradox was first described by the English economist after whom it is named, William Staney Jevons, in his 1865 book "The Coal Question".

Jevons noted that in the England of his time, coal consumption increased after the introduction of James Watt's steam engine, an engine that was much more efficient than the coal fired engine of his time.a machine that was much more efficient than the one designed by Thomas Newcomen, requiring a smaller amount of coal for each use.

Thanks to Watt's innovation, coal became a more efficient resource, meaning that with less coal, more energy could be obtained to feed the emerging industry in Great Britain. Faced with this fact, as coal became more productive, more and more factories introduced steam engines, causing the overall consumption of this resource to skyrocket, even though less coal was needed each time the steam engine was used.

Jevons argued that improvements in fuel efficiency tend to increase the use of a fuel, not reduce it.. Proof of this is that in the Britain of his time, after the introduction of Watt's steam engine, coal consumption became so high that there was concern about depleting reserves that were already dwindling at a dizzying rate.

Examples of this paradox

The main cause behind this paradox is that an increase in the efficiency of the resource used, be it a fuel or anything else, brings about a decrease in the cost of using that resource. A decrease in the cost or price of that good or service causes an increase in the quantity demanded by the law of supply and demand itself.

The increase in demand produces a rebound effect and it is considered that if such an effect implies an increase of more than 100% in the consumption of a given product or service, it would be considered that the Jevons paradox is being fulfilled.

In order to understand all this in a more tangible way let's look at real examples in which this paradox manifests itself.

1. Energy-saving light bulb

To better understand this paradox we can relate it to something everyday, something that is surely present in the life of each and every one of us: light bulbs, specifically energy-saving bulbs. We all know them, they are bulbs that not only consume less energy than more traditional bulbs, but also last longer than ordinary bulbs.

Our logic tells us that, as they are bulbs that consume less energy we will end up consuming less overall energy, but the truth is that the electricity bill is increased. The reason: Because of the excuse that as they consume "little", we leave them on unnecessarily. and, of course, as they are used without control, electricity consumption will not be reduced. It would be practically the same to have common bulbs but to make a rational use of them that to have low consumption bulbs and to waste them unnecessarily.

2. More efficient cars

It has been observed that drivers tend to travel more with their cars when they are more fuel efficient, thus producing a rebound effect in the form of increased fuel demand.This produces a rebound effect in the form of an increase in fuel demand. Because it costs less to travel, drivers use their cars more and consequently have to refuel more frequently.

3. Light foods

It may come as a surprise, but Jevons' paradox can also be observed in the world of food, especially light food. This type of food is characterized by being sold as low in calories, and actually has few calories compared to a non-Light food, something that can be easily discovered by reading the table of values of a Light food versus a normal one, such as diet cookies and regular cookies.

But despite being hypocaloric, light food does not help to maintain the figure, in fact they can make the person put on weight.. The reason is that those who buy this type of products end up eating them in large quantities with the excuse that as they are less caloric they will hardly put on weight. This causes them to eat so many quantities that they exceed by far the amount of calories they would ingest if they ate the same food in its normal version.

4. More roads

It used to be believed that building new roads and highways would effectively combat traffic jams. Ironically, traffic experts have found that just the opposite is true, that the more roads there are, the more used they are, and even the more traffic jams there are. the more roads there are, the more they are used, and even more traffic jams occur..

As people know that there are more roads and have more routes to get to different points, they are more motivated to take their vehicles and end up doing so en masse, which is why the roads are clogged.