What’s this Live Earth festival all about then? Haven’t we had one already?

Not to be confused with Live 8, Live Aid, or all that wet earth at Glastonbury, Live Earth is a music concert simultaneously taking place in eight cities – plus Antarctica! – around the world tomorrow. The London leg, starring Madonna, Beastie Boys and Red Hot Chili Peppers, will take place in Wembley Stadium, where they're still clearing up the plastic cups from last week’s Concert for Diana. In Shanghai, Cantopop stars such as Eason Chan will bunk down under the Oriental Pearl Tower with, erm, Sarah Brightman (perhaps she couldn’t face Wembley twice in a month). In Rio de Janeiro, Guns N’ Roses will join Jorge Ben to party down on Copacabana Beach, in a concert that differs from the others by being free, while even the South Pole is set to be graced by music, thanks to a bunch of research scientists who have formed a band and whose performance will be viewable via highspeed datalink.

Is Bob Geldof behind it?

No – in fact he seems to be in a bit of a huff about his idea being poached, sniffily branding Live Earth as “just an enormous pop concert”. He recently told a journalist that: “We're all f****** conscious of global warming. Live Earth doesn’t have a final goal. I would only organise [a gig such as this] if I could go on stage and announce concrete environmental measures from the American presidential candidates, Congress or major corporations.” He seems to have forgotten that his own recent awareness-raising concerts were criticised for the same lack of definition.

What exactly can a rock concert do to save the planet?

Well, the American Congress may well sit up and take notice, as Live Earth is the brainchild of Al Gore, the former US vice-president turned eco-warrior. Having won an Oscar for his documentary An Inconvenient Truth which told us where to stick our carbon emissions, Gore has joined forces with organiser Kevin Wall (who worked on Live 8 with Geldof) to create these eco-shows. Gore will even be presenting the New York event himself. Let’s just hope that he’s written his introductions in time, as his recent announcements that “We will have specific goals that will be very significant and hard-hitting” and “We will announce those before the concert then emphasise them heavily during it” seemed to be a bit light on substance.

Wall is hoping that Britain’s national grid will allow the BBC to ask its viewers to turn off all electrical devices – other than television sets, of course – at the same time. The grid is worried, however, that the stunt might blow a fuse, or several million, when they are turned on again.

Internationally, signing up to a seven-point pledge now seems to be the overall intention – all audience and TV viewers (a hoped-for total of 2 billion) will promise to “fight for” energy efficiency, sustainable business and the planting of trees, while also asking their government to do something “in time for the next generation”. It seems that Live Earth does not trade in specifics.

Don't pop stars fly around in private jets?

Yes, but it's not something we’re supposed to complain about. “Of course the Foo Fighters are taking a plane – they've got another gig that night and we have to get them to and from the shows,” says Bernard Doherty, the concerts’ official publicist. “Al Gore has to fly as part of his campaigning, but that is such a minor thing. Our response is that we are having a billion people watch this and if we can change 10 per cent of that billion’s thought process, then the call to action will have been a success.”

But at least one pop star has revealed his discomfort – Matt Bellamy of Muse (who are not taking part) told BBC6 Music: “Private jets for climate change, not sure about that.”

There are no such qualms from Spinal Tap, though – the spoof band will be “reforming” for the show, in a move that reveals the organisers to be blessed with either a great sense of humour or a complete lack of self-awareness. “We want people to worry about global warming as much as we do,” the Tap announced last week. “When we bother to think of it.”

How green will the actual concerts be?

Green measures are said to be a high priority, although once again, specific details are in short supply. Patrick Woodroffe and Mark Kenyon, the Wembley show’s lighting designers, say they are working on a much smaller lighting set-up than usual, and will be avoiding tungsten, as it uses twice as much power as LEDs. They are also using custom-built chandeliers called Eco-Clusters made of bunches of energy-efficient bulbs.

Other gig promoters are also looking into energy usage. Simon Moran, the managing director of SJM Concerts, says the shows are a great “inspirational” idea and that, in light of Gore’s campaigning, he will be introducing a range of environmentally aware innovations, such as the use of recyclable cups, at this year’s V Festival.

Are the concerts the same around the world?

No, they are carried out differently in each locale. Indeed, at the time of going to press, only Wembley had sold all its tickets, priced at £55, after a ballot entry application. Costs in other countries vary from £165 for the front row in New York to £18 in Johannesburg to an average of £40 in Tokyo. Are we to conclude, then, that the Brits are the most eco-friendly – or just better at buying tickets?

Ticketing expert Joe Cohen, the chief executive of Seatwave.com, believes the Wembley bill appeals to a wider demographic as it unites disparate acts such as Keane, Metallica and Pussycat Dolls. Indeed, Bernard Doherty says that more artists wanted to play in London than could be accommodated, hence Sarah Brightman ending up in China.

What else is going on?

There is a grassroots aspect to it all. Gore’s station Current TV has been filming at East London’s Premises recording studios, used by Arctic Monkeys and Lily Allen, where one studio is now run on solar power. Razorlight’s Johnny Borrell recorded a song for Live Earth there, and said: “I really enjoyed recording my first solar-powered song – the studio made tackling climate change easy.”

The studios are also endorsing a teenage battle of the bands on London’s Clapham Common, held on the same day as Live Earth by the C-Change organisation. So if you aren’t headed to Wembley, get yourself down there. Just try not to travel by private jet.

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