WILL money saved from using clean technology simply be spent on using more energy? Jevons paradox (or the Jevons effect) is named for economist William Stanley Jevons. In the 1860’s, he observed that technologically driven increases in the efficiency of coal-use increased coal consumption in a wide range of industries. Counter-intuitively to some, he argued that technological improvements could not be relied upon to reduce fuel consumption. Buyers simply use the savings to buy more energy. Such rebound effects as a batch of recent research reveals, are at work in energy markets yet are often overdetermined and misunderstood. Their occurrence suggests the need for carbon taxes in order to price environmental risk in energy costs. The basic logic of such taxes was sketched out in the 1920’s by another economist, Arthur C. Pigou, as the Pigovian Tax. He argued that landowners who allow their rabbits to overbreed and spill over to neighboring land, therefore damaging crops, have a financial responsibility for the damage. Such activity, often uncorrected by markets, is seen as a market failure. So its remedy is a tax or law to protect the rights of neighboring landowners.
Interest in both is keen among policymakers, thinktankers, bankers, and the general public as the tension between energy demand and supply increases. Pollution, global warming, declining oil reserves, and increasing demand for energy in the neoliberalized global marketplace underlie both the interest and the tension.
To the extent that they are at work, Jevons rebound effects in a system vary based on the scale of the market considered. For example Richard York of the University of Oregon finds:
A fundamental, generally implicit, assumption of the Intergovernmental Panel on Climate Change reports and many energy analysts is that each unit of energy supplied by non-fossil-fuel sources takes the place of a unit of energy supplied by fossil-fuel sources 1, 2, 3, 4. However, owing to the complexity of economic systems and human behaviour, it is often the case that changes aimed at reducing one type of resource consumption, either through improvements in efficiency of use or by developing substitutes, do not lead to the intended outcome when net effects are considered.
Dr. York’s work appears to reveal an instantiation of the effect. Across most nations of the world, developed and developing, he reports an average pattern, “…over the past fifty years is one where each unit of total national energy use from non-fossil-fuel sources displaced less than one-quarter of a unit of fossil-fuel energy use. When looking at electricity specifically, the displacement of each unit of electricity generated by non-fossil-fuel sources is less than one-tenth of a unit of fossil-fuel-generated electricity.”
These conclusions put a useful empirical foundation under recommendations found in Google.org’s clean energy innovation study: meaningful suppression of fossil fuel consumption requires adaptation of mainstream energy policy. Also looking at the international scale, Grist.org published a chart this week titled The mind-boggling rise in Asian coal consumption shown as Exhibit 1.
Coal going unconsumed in the U.S. is being burned with little scrubbing in China and India, further arguing for the need to decarbonize via international agreements. Liberalized trade (neoliberalism) needs alignment with a flow of trade that balances externalities – pollution – created by exchanges of resources and capital. This also complements York’s finding: shifts to renewables will be inconsequential if the total decarbonization rate isn’t decelerated, that is, if amounts are merely shifted from one market to another.
When Rebound Effects Are Perceived But Not Found
Then there is the contention of the paradox at work in driver behavior popularized as the ‘Prius Effect” in sources such as Conundrum and the Wall Street Journal. Their argument is that Prius owners drive more and thus erase their net carbon and energy savings for the system. However, the work of Ken Gillingham of Yale University and analysis from CO2 Scorecard show Prius owners rack up comparatively the same vehicle mileage as non-Prius owners.
This Prius Fallacy has a dual premise: Prius drivers drive more because they are paying less for gas, and/or they use their savings on carbon-intensive goods and activities.
Gillingham’s micro-dataset on personal automobiles contains information – further analyzed by Thinkprogess – which refutes premise one as the scale of the consumer. The plot in Exhibit-2 shows no significant difference in Vehicle Miles Traveled (VMT) by Prius owners vs. the rest of California’s drivers. (For those interested in statistical details on the data and diagnostic regression Thinkprogess’ analysis is worth a good study). Prof. Matthew Kahn of UCLA writing in the Christian Science Monitor reinforces these conclusions.
So in these cases when consumers switch from conventional cars to a fuel-efficient hybrids a meaningful reduction in gasoline consumption – up to 430 gallons per year for an owner who switches from an SUV— is also observed.