Happy birthday, US highways.

Alternative fuels are great, said James Howard Kunstler at the renewable energy fair last weekend, but unless we change our car-centric culture, which probably means dismantling the suburbs (described by Kunstler as "entropy made visible" and "the greatest misallocation of resources in the history of the world"), we're doomed. Coinciding with the 50th anniversary of the US interstate highway system, he says:

Biodiesel is cool and ethanol is cool and switchgrass is cool and all the alternative fuels are very cool. We have to talk about that a lot, and it’s going to have a great deal of meaning for the future of this civilization. But we cannot just talk about running the car. Because the truth of the matter is that no combination of alternative fuels that we know about or even have dreamed about will allow us to continue running the interstate highway system, Walt Disney World, and Wal-Mart.

Still, a few signs of hope:

• Algae-derived biodiesel: Said to be the most efficient source of biodiesel fuel, algae is "capable of producing 30 times more oil per acre than the current crops now utilized for the production of biofuels," writes Treehugger. "Algae biofuel contains no sulfur, is non-toxic and highly biodegradable. Some species of algae are ideally suited to biodiesel production due to their high oil content, in excess of 50%, and extremely rapid growth rates." As my brother asks, will the technology involved allow us to clean up Minnesota's mucky lakes and ease our oil dependency?

• And then there were three: Duluth, Minnesota, has become the third US Eco-Municipality. The city signed on to a Swedish sustainibility principles that involve the use of fewer natural resources and fewer man-made or synthetic chemicals. They're switching transit buses to biodiesel and making a rooftop garden at City Hall to cut air conditioning use.