The Big Tent festival
Now into its fourth year, Scotland's biggest eco festival was launched as part of the grassroots protests aimed at the G8 summit held at Gleneagles in the summer of 2005. Its central theme is "stewardship", which its organisers say boils down to "co-operation, mutuality, solidarity and ecological long-term thinking". They add that it is a "home for activists and thinkers, free spirits and debaters, ecologists and eco-builders, musicians and artists, traditional skills practitioners and learners".
Naturally, there's plenty of focus on climate change and "new stuff" for this year includes the Climate Challenge Ceilidh, a Climate Champion's Zone, and a series of Earth Action talks being held in conjunction with WWF Scotland. If all that sounds a little heavy, there will be bands, too, including Shooglenifty, Attic Lights and the Chipolatas.
• 25-26 July, Falkland estate, Fife; £40 (adult weekend camping ticket), bigtentfestival.co.uk
The Big Green Gathering
This is the granddaddy of the green festival movement, having evolved out of the original Green Gatherings in the 1980s and Glastonbury's legendary Green Fields. Deep greens are catered for with a mind-bending range of options including an area dedicated to the "horsedrawn 21st century" and a "sweat lodge" in the Tipi Circle. Now attracting 15,000-20,000 people a year, the festival - which returns after lying fallow in 2008 - also boasts its fair share of musical acts performing on stages powered by renewable energy. Acts confirmed so far include the "psychedelic sax man" Nik Turner, 3 Daft Monkeys and, perhaps most fitting of all, the "solar-powered, interactive experience" that is Rinky Dinks Mobile Cycle Powered Soundsystem.
• 29 July-2 August, Cheddar, Somerset; £125 adult five-day camping pass; £50 children aged 10-17, big-green-gathering.com
At this festival's heart is its big top, which claims to be "Europe's biggest solar-powered venue". The Croissant Neuf circus has been touring festival sites since the 1980s (the name refers to an East Anglian skiffle band whose members later went on to form the circus) but in 2007 secured its own permanent site for this now annual festival deep in the Welsh countryside. Its organisers - who limit attendance to 2,000 people to keep that "warm family feel" - say that "literally all" of the electricity on site is generated by solar panels and wind generators. "We're the only festival in the UK to achieve this," they add. If it's organic beer you're after, then you'll need onsite pub the Stagger Inn (glass is banned from the site as "for nine months of the year it is home to lots of sheep and cattle").
• 14-16 August, Usk, Monmouthshire; £80 (children £25), partyneuf.co.uk