Efficiency's Promise: Too Good to Be True

Amory Lovins once famously characterized energy efficiency as "the lunch you're paid to eat"; Steven Chu, the secretary of energy, has called efficiency a tool for reducing energy consumption and carbon output with minimal personal sacrifice.

Lovins, Chu and other efficiency enthusiasts are undoubtedly correct when they argue that we Americans could live regally on little more than we currently waste. But turning efficiency improvements into environmental gains isn't as easy as they make it sound. When I replaced the incandescent bulb in my desk lamp with a compact fluorescent, I expected the amount of electricity used by my desk lamp to decrease — and it did. But the broader, long-term impacts of that switch — both for my own life and for the world — are certain to be more complex.

Increasing the efficiency of energy-using machines has the practical effect of making energy cheaper, and when we make useful things cheaper we use more of them. This isn't an abstract argument, because the history of civilization has played out in exactly this way. Nearly every energy-consuming device I use today is vastly more efficient, in multiple senses, than whatever its equivalent was back in the early 1970s. Yet my energy consumption has soared, and so has the world's — not only over all, but also per capita and within every income stratum. Of course, correlation doesn't prove causation. But when the long-term correlations all run in one direction, we should take notice.

The challenge with efficiency gains is that we don't compost our energy savings: we inevitably re-invest the money in additional consumption. A study published in 2010 showed that, over the past three centuries, steady improvements in the energy efficiency of lighting have been almost exactly offset by the growth of new lighting applications.

And the actual impact of these new uses has been far greater, because growth in lighting has also had indirect energy consequences, such as lengthening the workday and making nighttime travel and recreation easier. Such changes have dramatically improved our quality of life, but they haven't shrunk our energy consumption, our carbon output, or our environmental footprint. On the contrary.

One way to see the flaw in the efficiency arguments of Lovins and Chu is to imagine that the global economy truly resembles the misleadingly simplistic problem that they say efficiency can solve. Imagine a primitive village in which the only energy input is food and the only way to transport anything is to carry it or drag it over the ground. Now invent the wheel.

If the village were Lovinsland, this increase in efficiency would cause food consumption and production to fall. In the real world, though, we know that the villagers will reinvest their sudden energy surplus, leading to a cascade of mutually reinforcing increases in consumption of all kinds. And we know this is true because, in the real world, it's exactly what we've done.