Arnold Schwarzenegger has four Hummers and likes nothing better than getting up at 5 a.m. to ride his Harley Davidson to the beach for breakfast. Yet "The Terminator" star insists that should not stop him from being an environmental evangelist.

"Saving the planet is also about technology," the former California governor told AFP, putting his foot on a chair and wagging a skull-ringed finger to make his point.

Three of his Hummers run on hydrogen, vegetable oil and bio-diesel and he's hoping to put an electric engine into the fourth. "You know one day soon we are going to have hydrogen-fueled planes. We can get rid of this dirty diesel tomorrow. "I hate it when environmentalism comes down to ‘you can't do this and you can't do that.' There's a bad habit of shaming, guilt and finger pointing. ‘Don't smoke this, don't take a jacuzzi and don't take a plane.' Everything's bad."

Now on top of the global R20 network of regional leaders he has put together to fight climate change, Schwarzenegger the activist has got behind a new documentary at the Cannes film festival by the son of undersea explorer Jacques Cousteau which he also narrates. "Wonders of the Sea 3D" will make "people fall in love with the ocean", he declared. "And if they love it they will protect it," he said.

"The oceans give us half the food we eat and half the oxygen we breath and we better protect that. Seven million people die every year because of pollution."

Even such apocalyptic statistics cannot survive long in the white heat of the Austrian-born star's can-do charisma. "Look, we can do it, we can save the planet with people power and positive attitude. If you want people to change you got to make them feel good about it. But I never thought I would have the biggest movie of the year with ‘Terminator 2', and that I would be doing comedy or politics."