The Jevons Paradox

There was a pressing Coal Question long before the recent one, just as urgent and with consequences as dire.

The latest iteration centers on whether coal can save us by providing cheap and abundant energy for a long, long time, if only we can make it clean enough.

The 19th-century question preoccupied the considerable intellect of political economist William Stanley Jevons, who correctly foresaw coal's unsustainability as fuel for industrial England's incredible productivity, prosperity, and rise to world power.

"Are we wise," he asked rhetorically, "in allowing the commerce of this country to rise beyond the point at which we can long maintain it?"

While credit is due Jevons for his prescient analyses of (get ready) finite energy sources, sustainability, limits to growth, overpopulation, overshoot, post-global relocalization, energy return on energy input, taxation of the energy resource, renewable energy alternatives, and resource peaking (whew!), his most intriguing contribution is to the issue of energy conservation efforts, and whether they do enough to abate energy demand and forestall resource depletion.

Jevons is known for the "paradox." The Jevons Paradox states that given efficiency improvements in gadgets that use energy to get work done, demand for those energy sources will go up, not down, because they are now less costly.

"It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption. The very contrary is the truth."

Watt's steam engine is the case in point, for Jevons saw that innovations in its design over the predecessor engine improved overall efficiency, reduced the effective cost of energy and in so doing broadened the application of the use of the engine and thereby increased the demand for coal.

Jevons was on the lookout for mitigation measures, assuming as he did that coal was finite and that energy depletion posed a long-term threat to English society. But conservation, it would seem, was not the answer.

This idea is finally getting some play, although in slightly altered form, in the contemporary concern over whether automobile fuel economy is achievable or even desirable.

Take the Prius. Increasing a car's fuel economy doesn't necessarily get drivers to drive less, because they have (theoretically) cut the cost of their gallon of gas in half. As David Owen puts it in the New Yorker last month, "Increasing the fuel efficiency of a car is mathematically indistinguishable from lowering the price of its fuel; it's just fiddling with the other side of the equation."

In other words, auto fuel efficiency, delivering drivers more gas for the buck, cannot do for the environment what doubling the cost of gas did last year by pushing down oil consumption, stimulating investment in renewable energy, increasing public transit ridership and killing the Hummer.

The same can be said for those new compact fluorescent bulbs that, while delivering longer watt-hours of life, may inadvertently promote less vigilant behavior. What's the point of conserving if you leave the lights on when you walk out of the room?

Bottom line: efforts to solve the energy crisis may in fact be hobbled, not helped, by energy efficiency.

To say the least, The Jevons Paradox is alive and well, and casts a pall over the energy debate today.