When Lorde, Little Simz and Wet Leg stride on to stages in Bristol this weekend, they will not only be entertaining tens of thousands of festivalgoers but taking part in what is being billed as a world-first clean power project.

The two stages at Forwards festival on Clifton Down are being driven almost entirely by green power – a combination of hydrogen and mobile batteries charged with sustainable energy.

Across the globe, artists and major festivals have been taking action to make their events more sustainable. But what makes the clean power pilot (CPP) scheme that is driving this weekend’s festival different is that it is backed with regional public money and political will. Over the summer, the CPP has guaranteed a secure source of green mobile power to festivals, events and television film crews.