Articles by Clark Williams-Derry

Density Star

From the New Urban News comes this nugget:

Researchers presented findings at the Congress for the New Urbanism annual conference that show substantial energy savings from higher-density urbanism -- greater savings than can be achieved from the US government Energy Star program.

As the chart on the left shows (if you can read it -- sorry it's so small), even small increases in density can yield substantial energy savings; increasing residential density from 3 housing units per acre to 6 units per acre actually saves more energy than the average efficiency boost provided by Energy Star appliances.

Now, this shouldn't be much of a surprise, since it's been well established for decades that people who live in compact neighborhoods drive much less than people who live in more sparsely populated suburbs. Still, it's an important reminder: Neighborhood design is a powerful determinant of how much energy we use.

But for some reason, when people talk about making our transportation system more fuel efficient, they typically talk about improving the efficiency of vehicles, rather than of neighborhoods. Efficient vehicles have a high-tech cachet, I guess. But if anything, efficient neighborhoods are even more important than efficient vehicles. Hybrids and biodiesel vehicles do save fossil fuels and reduce pollution, obviously; but by reducing how much people need to drive, efficent neighborhoods not only save fuel, but also reduce other costly externalities, ranging from highway spending to car crashes.

The question of whether to buy locally grown food is not as clear as it might appear.

When shopping for food, how important is it to buy local? This question isn't rhetorical: I no longer know quite what to think about this. Obviously, transporting food long distances requires fossil fuels and creates air pollution, among other ills. So all else being equal, it's better to buy local. But how much better, I'm just not sure.

Studies such as this one (reported on here by the BBC, blogged about here) suggest that, in terms of net environmental impact, it's even more important to buy local than to buy organic. The authors of the study didn't look at human health issues, but did attempt to quantify all sorts of environmental "externalities" -- i.e., costs not borne by the consumer -- resulting from food production. And they found that transportating food was far and away the largest component of external environmental costs. In other words, the closer to home the food is grown, the better it is for the planet.

Critics of new urbanism’s grid street pattern miss the point.

One of the defining characteristics of sprawl is a branching street pattern -- one in which cul-de-sacs feed residential streets, which feed local arteries, which feed thoroughfares, which ultimately feed freeways. It's a design that can work fine for cars, but not so well for people. I spent (or misspent) part of my childhood in that sort of neighborhood. There were houses that were literally 100 yards from my house as the crow flies, but nearly a mile by the road network. That sort of thing discourages, you know, walking and stuff. Which is one reason why people who care about promoting walking and biking as transportation prefer an interconnected street network to a hierarchical one.

Now, Wendell Cox, a smart-growth skeptic and fellow of the Heartland Institute, writes in defense of the cul-de-sac:

The ranking of most eco-friendly cities gives too much weight to good intentions.

Via Planetizen News, here's an interesting sustainability ranking for 25 US cities. Now, I haven't had time to look through the methods thoroughly. But my first impression is that it gives undue weight to intentions, and not enough to actual performance.

For example, Portland does exceptionally well in climate and energy policy, while New York City's rank on energy policy is only middling. But this only measures what cities say about energy, not what they actually do. In the real world, however, the climate doesn't care about good intentions. And in point of fact--at least where transportation emissions are concerned--Portland eats The Big Apple's dust. Gotham has by far the most energy efficient and climate-friendly transportation system in the U.S., largely because higher residential densities and a good mix of residences, jobs, and services let many New Yorkers get around on public transit or on foot. So even though Portland is doing a good job of talking the talk on energy efficiency, in New York City they're (literally) walking the walk.

That's not to say that Portland's energy policy is irrelevant, or that rankings like these aren't a useful exercise. Far from it.  Still, actions speak louder than words -- and any attempt to measure sustainability should look far more closely at what cities actually do than at what their leaders say.