Co2penhagen is a new festival which takes place at Denmark's Technical University this weekend - 5-6 September. They're billing themselves as the World's First C02 Neutral Festival.
There will be rockin' concerts, bars and events and the festival will produce it's own energy to run the whole gig all weekend.
Here's how they plan to do it.
It's a cool initiative. What's best about it is that it is really rather mainstream. Far from an eco-geek, treehuggin' love in, C02penhagen has managed to generate an enormous amount of press and attention. The acts giving concerts help - they're big local names - but the whole feel of the festival is that it's a given. It's carbon neutral. It's not strange, it's normal.
An important step on the road to mainstreaming environmentalism.
And on Saturday there's a bicycle parade starting from Kongens Nytorv at 09:30. Breakfast, speeches and a bicycle ride out to the University north of Copenhagen.