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I spotted this mobile advertisement up in Columbia Heights a little more than a week ago—and then an identical skinny truck drove by me near Cleveland Park a few days later.

It appears the truck(s) carries no cargo or passengers. It simply drives around, clogging up the roads, doing what trucks do, to promote free home energy audits.

The District Department of the Environment doesn’t exactly have the best track record on environmentally friendly advertising. Back in June, DDOE printed up 100,000 doorhangers to publicisize the launch of the Mayor’s Conservation Corp. summer program.

The explanation then:

The point of the doorhangers, [DDOE spokesperson Alan Heymann] says, is “to announce to the community that the conservation corps is going to be out doing this type of work” and to solicit project suggestions from residents.

But why use dead trees to do so?

“Not every resident of the District of Columbia is on a listserve or a blog,” he explains.

As for the truck advertisements—driven around by Mobile Media Inc.—Heymann says the campaign’s brief, and the trucks run on bio-diesel.  So that’s good news.

This is the first time we’ve used mobile billboards to advertise energy audits, and it’s a short-term campaign that’s due to end next Wednesday. We’re looking to attract about 4,000 homeowners to sign up for free energy audits in the next fiscal year, so the truck is targeting areas of low participation in the program.

Why weren’t those same people targeted with, say, advertisements on buses or bus stops? Heymann didn’t know. “The thinking was to give it a shot,” he says.