When it comes to saving resources, efficiency and conservation are often spoken of as one.
Last year, for instance, announcing a new grant program, U.S. Secretary of Energy Steven Chu touted "the cheapest, cleanest and most reliable energy technologies we have -- energy efficiency and conservation," without distinguishing between them.
Both practices, of course, can potentially reduce the damage we do to the planet. But they are also very different, not least in realizing that potential.
Efficiency means using technology to get more out of the same energy. Gregory Reed, director of the University of Pittsburgh's Power and Energy Institute, cites the example of a new air-conditioner that still keeps your house at 70 degrees but burns fewer kilowatts.
Conservation means simply using less. "Conservation says, 'I'm not going to turn that air-conditioner on at all, or I'm only going to turn it on a couple of hours a day,'" says Reed.
And efficiency and conservation can overlap in technologies as simple as insulation, which lets you maintain the same temperature with less fuel.
But saving energy is saving energy, right? Why does it matter how?
One difference involves our intentions. When we conserve, we do so explicitly to save resources. Efficiency, conversely, can be the means to other ends (like comfort): It can improve even while consumption rises.
In fact, that's exactly what has happened, big-time. While our machines are ever more efficient, America's energy appetite grows. For instance, from 1990-2005, reports the International Energy Agency, per-capita electricity usage in the U.S. grew nearly 17 percent, even as our energy-intensive industrial base declined. Our per-capita consumption remains about 50 percent higher than average for a developed nation. It's twice Germany's.
The phenomenon of consumption and efficiency growing together has a name: the Jevons paradox, named for the British economist who, in 1865, noted that coal usage rose even as Britons burned it smarter.
Efficiency effectively makes resources cheaper. Thus, as Reed notes, while he grew up in a house with one refrigerator and one black-and-white TV, families today can afford to run two fridges (and a freezer) and two TVs -- plus three computers.
And that's true even though electricity production and delivery remain stunningly inefficient. Take coal, which generates nearly half of U.S. electricity. Reed, whose Power and Energy Institute works with industry and utilities, says that up to 88 percent of the energy in a lump of coal vanishes before it reaches your outlet, mostly as waste heat. That flat-screen is wasting even more watts than you imagined.
Meanwhile, if we'd worked as hard to conserve as we did to get efficient, we might each be using half the energy we did a few decades ago. "Conservation is the first step always," says Jeaneen Zappa, Allegheny County's sustainability manager, whose tasks include things like getting county employees to douse the lights in empty rooms. "Behavioral change is the key to success of any program."
But getting people to conserve is hard. For one, while our grandparents called it "thrift," conservation now strikes many as deprivation -- "shivering in the dark." Even conservation that doesn't affect quality of life -- unplugging unused appliances, say, to prevent "phantom" electricity use -- takes more sustained, conscious effort than simply buying new appliances. Nor is conservation as sexy as the long-promised "clean energy breakthroughs" President Obama referenced in his State of the Union address.
Most importantly, using less doesn't always seem worth the trouble. "For a lot of people, [energy] doesn't represent that big a bite" of their budgets, says Ernie Sota, of Sota Construction. "It's still too cheap." Sota reports that even buyers of his new and renovated green houses are more concerned with location and aesthetics than with utility bills.
It's hard to imagine reining in consumption without policies like California's, whose laws and programs promoting efficiency have held per-capita electricity use steady for three decades even as usage ballooned nationally.
Unless, that is, something else makes energy more expensive. Zappa, for one, argues that using less before energy prices rise just makes sense. "We see it as an important business risk," she says.
And conservation, it seems, remains the gold standard. Efficiency can help -- provided it's done with conservation in mind.