So let's go back to Sheffield to that whole plan by McDonald's to try and burn the waste and the leftovers from their burgers and the packaging to try and turn it all into household energy. Lucy Manning reports from Sheffield.

Their ads say their customers are loving it, but what no one much likes is the amount of rubbish McDonald's and other big businesses generate every day.

So the Golden Arches are trying to take on a greener tint. A pilot project in Sheffield will see 11 MacDonald's restaurants turn their waste into heat and electricity for local buildings. It works something like this: take a MacDonald's burger, chuck it away, take that and a hundred tons of rubbish each restaurant generates a year. And instead of taking it to a landfill, drive it down the road to an energy recovery plant, mix it up with some of Sheffield's other rubbish, burn it in an incinerator and get electricity and heat.

We've got a real serious issue to address here in Britain overall. And that is there is just too much rubbish being buried in the land. There is too much waste going to landfill. I think it's incumbent on big, big businesses, business like McDonald's to try and find innovative solutions ‘coz we all have aspirations to send zero waste to landfill. But bringing that into reality is something of a challenge for us.

MacDonald's has done much over the last few years to try and rebrand itself. And now like a lot of other companies, it's choosing to go down the green route. But will my filleted fish, milk shake and chips really make a difference to the planet.

The amount of electricity and heat it creates is not gonna be that great. In fact, this entire scheme covering 11 stores is gonna provide the heat and electricity for about 50 homes, that's all, 50 homes. And even if you extended it across the whole of the MacDonald's estate, it would only be 5,000 homes. So it's good, but it's nowhere near enough.

What more do you think needs to be done for McDonald's to go green? Well, there is an astonishing fact that they have released, haven't they? They've told us that each store, each individual MacDonald's produces 100 tons of waste a year, that is the most enormous amount of waste. And that what MacDonald's really ought to be working on now is trying to diminish that, trying to cut that to a reasonable level.

But MacDonald's says it has tried to minimize packaging and improve recycling. Its delivery vehicles will soon be powered with used cooking oil and it hopes it can lead the way on dealing with waste.

One things that MacDonald can't bring is scalability to positive programmes such as this, so if being proven out in its 11-restaurant green city trial, then the potential across 1,200 restaurant estate and across the broader food industry and general commercial waste is huge.

But there're only around 20 of these energy recovery plants across the country and unless more are built, that's going to mean long drives for the rubbish, reversing any green benefits and green campaigners say no matter how hard MacDonald's tries to be environmentally-friendly, the fact (that) its core product is beef means it will always struggle. The vegetarian society has launched this campaign, warning people about what it calls the dangerous emissions from cattle, more deadly it says than the effect on climate change of the transport system across the world, but this link between diet and global warming may be more difficult for the Big-Mac-Generation to stomach.