The documentary No Impact Man chronicles the year that New York writer Colin Beavan, along with his wife and daughter, embark on a quest to have zero impact on the environment. To achieve their goal, they only purchase locally produced food, curb their shopping habits and eventually relinquish electricity, among other drastic measures.

At the time of making the film, in 2007, the family’s story made the pages of the New York Times Style section, much to the chagrin of fellow New Yorkers and environmentalists, who believed Beavan’s actions were an exercise in “self-promotion”. One annoyed reader emailed Beavan, saying: “It’s crazy people like you who give us environmentalists a bad name.”

However, audiences who managed to catch the environment thread of films at the Sydney Film Festival, would know that larger-than-life protagonists are a fundamental element in these documentaries. Like No Impact Man, the films The Burning Season and Big River Man feature protagonists who are memorable or endearing, yet lacking an environmental science background.

In the latter film, overweight endurance swimmer Martin Strel, swims the length of the Amazon River to raise awareness for deforestation and cleaner waterways.

“I would like to stop people from harming the Amazon,” Strels says over the phone, in a thick Slovenian accent. “So I send a message around the world saying how precious this part of the world is. I hope in the future that many, many people take notice.”

“People who tear down trees do it to earn a lot of money, because it is not possible to do it any other way on the Amazon. Deforestation is for me difficult to understand, it is terrible. It is better not to see, because there is fire where a lot of trees once were.  Many people in the jungles don’t understand why this is wrong,” Strel says.

Throughout the film, which was also made in 2007, the then 53-year-old suffers from hallucinations, guzzles bottles of wine and wears a piece of white cloth over his face to protect him from the sun – elements which boost the film’s entertainment factor.

“The call was to not make a boring documentary. We wanted to do something bigger than just a documentary about swimming and the environment, we wanted to do a character feature film,” says Strel's son Borut, who narrates the documentary.

“Martin is a big character, he’s much more than a swimmer. In order to get people to relate to him, an ordinary documentary is not enough. We knew from the very beginning that we’d like to do that,” Borut says.

Tony Mohr, the Climate Change Program Manager from the Australian Conservation Foundation (ACF), saw No Impact Man and Big River Man at the Sydney Film Festival and says it’s impressive to see environmental issues featuring in mainstream documentaries: “These films lead to some good conversations between people who aren’t already committed to environmental issues.”

“There’s always difficulties about what the right message is. These films had the right message for their audience,” he says.

“Colin [Beavan] is not preaching to everybody that they have to go that hardcore, but he’s showing what’s possible. And Martin [Strel] would probably do these swims anyway and get a lot of attention because he’s such a character, so it’s good that he can raise awareness while he’s doing it. In the question-and-answer after the screening at the Festival he showed a greater depth of knowledge about the environment than he does in the movie.”

However, Mohr says that politics should have played a bigger role in each film.

“There’s always a need to not lose sight of the big political picture. Both films touched on that, but only generally. They illustrate the problems quite well but neither of them really bring home the political dimensions that both problems involve. However, if you’re introducing someone to environmental issues through a film and it’s only about politics, they’re probably going to get turned off,” says Mohr, who liked Big River Man better as the story was a more compelling one for his money.

“For those of us who work in the environmental area No Impact Man doesn’t say anything new about environmental issues. It was the same with Al Gore’s Inconvenient Truth. On the one hand it showed stuff that we’ve been talking about for a long time, but on the other hand it reached an audience who didn’t know these things. It’s all about delivery and the types of audiences they get out to, so if these films get out to a different audience, then I’m all for it,” he says.

Cathy Henkel, the director of The Burning Season, another environment documentary that showed at the Festival, was inspired by the actions of the film’s protagonist and hopes audiences will react in the same way. Her documentary follows the plight of then 29-year-old Dorjee Sun, who offers a solution to massive deforestation in Indonesia in the way of a carbon trading scheme.

“Dorjee’s determination and his approach to climate change really inspired me. The fact that you can make money and save the environment is a completely new concept for people, and now I realise that it’s really essential that we have to involve everybody to protect our environment.”

Henkel says that the film creates a conversation about climate change and carbon trading, and that what Sun proposes is not a “perfect solution”.

Like No Impact Man’s Colin Beavan, Henkel wants to raise discussion rather than preach to people about what they should do.

“I haven’t made a film that says carbon trading is the best solution for this problem,” Henkel says. “It’s a story about one young man who pursues that solution for saving the Indonesian rainforest. It’s really there to provoke discussion.”

The Burning Season is less comedic than No Impact Man and Big River Man, but it does have humourous moments. “I think using humour is wonderful if you can find a way, because when people laugh, just as when they cry, they open up and open their minds to the ideas of the film,” Henkel says.

Henkel believes that Sun is not interested in being famous, rather he’s interested in finding solutions and seeing them work.

“He's gained more of a profile, and he will continue to, not just because of the film, but because he’s offering a different solution to the problem. Up until now it’s been a deadlock with environmentalists on one side and big companies on the other side. What Dorjee’s offering is a way through the middle whereby big companies can actually work to save the environment. He’s had interest from government leaders across the globe for his ideas and way of thinking, which is quite innovative. Dorjee’s getting a high profile for those reasons, the film is just adding to that,” Henkel says.

However, it may be The Burning Season's supporting characters who earn the type of high profile that Strel is receiving, predominantly for his quirky behaviour. Governor Irwandi Yusuf, the rock-and-roll leader of Aceh, who backs Dorjee’s proposal is one such character.

“I really enjoyed hanging out with Irwandi both in Aceh and in America. I think he’s very brave and smart. He appeals to me and hopefully he appeals to audiences too,” Henkel says. “Also the palm oil farmer is an endearing character. He made it very clear that he wasn’t the bad guy in the story, that he was willing to look at his practices and change. I really admire that.”

The supporting characters in No Impact Man, Beavan’s wife Michelle Conlin and toddler daughter Isabella, also threaten to steal the show. While Isabella relishes her new non-disposable nappies, Michelle reluctantly adjusts to a year without Marc Jacobs, electricity and junk food. Now that’s entertainment.