Robert Redford is an eco-hypocrite, film claims

For years, they've preached green living while travelling the world in SUVs, limousines and private jets. But now Hollywood's foremost tree-huggers face the prospect of being exposed as eco-hypocrites – in the very medium that finances their extravagant carbon footprints in the first place.

Robert Redford became the latest movie star to have his environmental credentials publicly ridiculed on film this week, when a hostile documentary was released in which he stood accused of failing to practise the environmentalism that he so vehemently preaches.

The short film, Robert Redford: Hypocrite, was released on Friday, via YouTube, to coincide with the closing days of his Sundance Film Festival. Depending on your point of view, it represented either a cheap hatchet-job or a stunning evisceration of a pioneering green activist who was once lauded on Time Magazine's list of environmental "superheroes".

According to the film, Redford recently sold a dozen plots of land near to the Sundance ski resort in Utah, which he owns, to developers seeking to build luxury homes there. The revelation is especially contentious because each of the sites sits on an undeveloped ridge, in what was previously wilderness. Ironically, Redford recently stuck his head above the parapet to lobby against a similar project in California's Napa Valley, where he keeps a home. Mind you, the film points out, the nimby-ish actor did not stand to profit from the Napa development. The plots of land near Sundance, by contrast, fetched him around $2m each.

"It's the hypocrisy that gets me," said the film's Irish director, Phelim McAleer. "He's taking a lovely virgin ridge and building McMansions on it. Granted, they're nice, lefty, eco-McMansions. But they're McMansions all the same. At the same time, he's trying to stop other people from building houses in a nice spot." The film also points out that Redford, 74, has often called for the world to reduce its carbon footprint, while simultaneously accepting the shilling of United Airlines, for which he performed voiceovers in aTV advert proclaiming that "it's time to fly".

Yet the Sundance Kid won't be the last Hollywood liberal to face the howitzers of McAleer, who became a known figure among climate change deniers in 2009, when he released the controversial feature-length documentary Not Evil Just Wrong, which disputed global warming science.

In a previous short film finished two months ago, McAleer, ridiculed the environmental credentials of James Cameron. The Avatar director preaches "living with less", it noted, while owning a helicopter, a fleet of submarines, three Harley Davidsons, four sports cars and a private yacht.

Aerial footage of Cameron's Malibu estate in the film revealed several large houses, at least three heated swimming pools, a fire engine, but not one solar panel or wind turbine.

McAleer now has a "hit list" of other celebrities he regards as hypocritical. He intends to make and release a new film laying into one of them every two to three months. He also plans take aim at some US politicians.

"As a film-maker, this is the gift that keeps on giving," he says. "We have a hit list, and as well as the usual Hollywood suspects it has people like John McCain on it – a man who has backed climate-change legislation, while being unable to remember how many homes he owns."

Unlike many independent film-makers, who can find themselves in dire financial straits, McAleer says his short pictures are self-financing. On YouTube, they drive traffic to his website, where fans purchase DVDs of Not Evil Just Wrong. The Cameron film clocked up 175,000 "views".

"There seems to be something about the environmental movement that attracts hypocritical people," he added. "Most are rich, and while they don't want to give up what's made their life happy, they're happy to tell other people not to, say, drive an SUV. Making films that knock them is basically like shooting fish in a barrel."