In road-building circles, the "concrete vs. asphalt" debate is every bit as intense as that drunken discussion (eventually devolving into a weepy shouting match) every year at Thanksgiving dinner between your right-wing uncle and your pinko vegan cousin.
On the rhetorical battleground, one of the strongest anti-concrete arguments has always been: "So pricey!" But perhaps that is changing. In Minneapolis, when bids came in on a project that includes new bus lanes and wider sidewalks (on Marquette and Second Aves near the convention center, for those familiar with the local terrain) the concrete and asphalt options cost more or less the same, according to a local business paper.
The underlying trend here is that asphalt's price is closely tied to the price of oil. And when a barrel of crude when into three-digit land last year, asphalt was suddenly as expensive as concrete.
Even though the price of asphalt has come down a bit recently (according to many reports), this could still be a key moment in the debate.
We'll take the opportunity to pick sides a bit and say we prefer using concrete whenever possible. Yes, it's bumpy and loud to drive on and the initial construction costs have historically been a lot higher. But it's also light of shade — that is, it absorbs a lot less heat. New concrete has an albedo as high as 0.80(meaning it reflects about 80 percent of the sun's heat). New asphalt has an albedo as low as 0.05 (it absorbs 95 percent). That's a *huge* difference — greater, in fact, than the difference between snow and seawater.
As we wrote about hereand here, a trio of well-regarded scientists have argued very persuasively that all the dark rooftops and roadways in our cities are heating up the planet, and we could buy a lot of time–think 20 years–in dealing with climate change if we lightened up on the double. Steven Chu, our Nobel laureate Secretary of Energy, has even weighed in in support of the idea. (We think he should put some stimulus money where his mouth is.)
We have a hunch that oil prices might headed back over $100/barrel in the next year or two. If that scenario plays out, it might offer a perfect opportunity to start migrating over to lighter pavements as a matter of national (and international) policy. Let the Great Whitening begin.
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