HOWZAT

More information: www.bananalink.org.uk

CHICKEN

We’ve developed a fairly serious chicken habit in recent years: 20-plus kilos per person annually, or about one chicken a week for a four-person household. To meet this demand the British chicken industry kills 800 million birds a year, 98 per cent of which are raised in intensive systems.

The energy needed to raise the birds and produce their food is equivalent to the annual output of a decent-sized coal-fired power station, or one per cent of the UK’s electricity demands. And that’s before you consider the energy used in processing, refrigeration, packaging and retailing.

Greenest: chickens in the back yard

To be truly green, chickens should eat no more than the food you grow for them, which means you need about two-thirds of an acre of a cereal crop, such as wheat. Their waste should be recycled on to your land.

Dark green: conventional broiler chicken

Breeding birds for ultra-rapid growth means cramming up to 40,000 of them into a windowless, dimly-lit shed at a density of 16 per square metre, where they shuffle around in their own excrement during the whole of their short and unpleasant 40-day lives. However, if greenhouse gases are your main worry, you should opt for one of these miserable chickens every time. Because of their short lifespan, fast growth and crowded housing, these overbred, barn-reared chickens end up using 32 per cent less energy per tonne of meat to rear than organic birds.

On the negative side, their feed will itself have been intensively produced. Plus, chicken production on this scale produces tangible levels of pollution: the average ammonia levels inside intensive broiler houses are above the safe level for humans.

Still, at least broiler litter gets recycled: two-thirds of it is composted and used on the land and the remainder is burnt in power stations (so yes, one of your light-bulbs is glowing courtesy of chickenshit).

Quite green: organic

Their feed, which accounts for 40 per cent of the energy cost of chicken production, is organic, which means it won’t have been produced with fossil-fuel-based pesticides or energy-intensive artificial fertilizer. However, organic chickens live in small sheds of 1,000 birds and have double the lifespan of the broilers – which means they need much more food.

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