The religious environmental movement is potentially key to dealing with the greatest problem humans have ever faced, and it has never been captured with more breadth and force than in RENEWAL. I hope this movie is screened in church basements and synagogue social halls across the country, and that it moves many more people of faith off the fence and into action.

To me, it's more important to take the 60-70% of people who really understand that there's a problem [of climate change] and get some percentage of them active than to try and stamp out the last embers of pre-scientific thought.

That's when the vast consensus of the world's climatologists, brought together by the UN and The Intergovernmental Panel on Climate Change, really announced that this was going on, and since then the accumulation of data and wickedly hot years has served to only congeal that consensus much more firmly.

Solar power seems to be truly bipartisan in its appeal.

There's always the danger that people will simply sign online petitions, the way they used to just mail in checks, and there's the greater possibility we'll just spend our whole lives staring at screens and never get anything done.

In the States we've had by far the largest demonstrations in the last few years. The largest civil disobedience actions about anything in US history in the last 30 years have all been centred around the climate.

I don't think the fossil fuel industry will listen, not until we build up a lot of pressure. I do think we can persuade some shareholders that they don't want to be involved in this enterprise.