COLIN BEAVAN'S yearlong act of abnegation, recorded in the exasperating documentary No Impact Man, can make you as depressed about the possibilities of the environmental movement as an exposé on drowning polar bears. Beavan became the flavor of 2007 when his blog was publicized by a New York Times story. It was subsequently echoed in magazines and on television. Beavan's experiment: an attempt to make no carbon footprint for a year while living in his New York city apartment. Along for the ride—goodbye, city life, as Eva Gabor once sang—was Beavan's spouse, Michelle, a senior writer at Business Week. Their 2-year-old child, still in diapers, also contributed.

Beavan gave up coffee, the movies and anything else that cost energy. Most notoriously, he and his family gave up toilet paper on the grounds that it was difficult to tell if the paper had been recycled. Somehow Beavan misunderstood the wrath and snark to come, not on the grounds that his butt smelled but because he'd gotten into The New York Times ahead of all his attention-seeking friends. Pre-stunt, Beavan was a Ph.D. in electrical engineering, and he spent extensive time as a social worker in 1980s England. He's a perplexingly naive figure, then, watching his long-suffering wife yearning for coffee and a trip home to see her parents. Moreover, since she's turning 40, she has the urge to add another little consumer to this world: a prospect Beavan objects to not because of the carbon footprints to come but because of a new baby's effect on his career.

It's hard to take this documentary as it probably ought to be taken: as a cute pointless anecdote meant to spur a discussion. Of course, there is charm in watching a family shopping at the farmers market in Union Square, bicycling through New York and trying (unsuccessfully) to figure out a nonelectrical way to refrigerate a baby's milk. Mull over this stuff, and you start to go Edgar Allen Poe–level obsessive about it. Was the steel for his solar panels milled sustainably? The grain from the locally made baked loaves—did it come from upstate New York or from the prairie 2,000 miles away? South of the Rio Grande, there are many small coffee farmers dependent on conscience-stricken urbanites—would patronizing them have been a good exception to the no-carbon rule? And, lastly, no-carbon indeed: What fuel are they using to cook their endless meals of squash?

I finally felt a ray of common sense bursting in when a fellow New Yorker—a portly survivor of the 1960s who works a community garden—patiently sits Colin down and explains to him that the chances of radical change are nil when they're publicized by the same establishment responsible for the rapine of the planet. This study ends right where you guessed it would—right where it should have begun—in a program of sensible choices and behavior modification, rather than stunt-driven whackadooism guaranteed to inflame consumers with terror of scarcity and the image of Obama snatching away their Charmin from their cold dead hands.

NO IMPACT MAN (Unrated; 90 min.), a documentary by Laura Gabbert, opens Oct. 2 at Camera 3 in San Jose.

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