The Atlantic's Cities blog points an energy conservation problem caused by people having trouble with math:
A significant – and seldom noticed – part of the solution lies with some fairly low-tech infrastructure: our houses, and the relationship they have to each other and where we want to go. A growing body of data has mapped the carbon footprint in sprawling suburbia of a single-family home, which is located nowhere near the grocery store, the job center or the shopping district. We can now compare that footprint to a multi-family home in a walkable urban neighborhood. And it turns out the gap between those two models may offer a serious – and perhaps more palatable – place to start thinking about the problem of climate change.
It doesn’t solve the problem to buy a hybrid and retrofit your house if all of that takes place 20 miles from your job. You’d still consume more energy (“suburban single family green”) than an urban household without the latest green tech (“urban single family”). And that has as much to do with associated transportation emissions as the size and efficiency of your home.
Unfortunately, without adequate gasoline taxes, adequate public transit spending, adequate land use legislation, or adequate acceptance in the U.S. that we can't sustain our way of life much longer, people will still buy houses in the exurbs and use half a tank of gas driving to work every day.