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Tesco, for example, has made some bold commitments, to which it might eventually be held. At the moment they are weeviled with contradictions and evasions. In his speech on Thursday, the company's chief executive, Sir Terry Leahy, spoke of the sophisticated new refrigeration techniques that Tesco will use, which will allow it to reduce its consumption of climate changing gases called hydrofluorocarbons. But at no point did he mention an environmental technology called the door. How can you claim your stores are sustainable if the fridges and freezers don't have doors?
Tesco's press officer was unable to tell me whether the energy savings the company has promised (50% per square metre by 2010) will be independently audited. If not, the promise is worthless - a company can make any claim it likes if there is no outside body to hold it to account. Leahy announced that he would respond to one of the biggest complaints of the green groups by cutting the distance Tesco's products travel, especially by air. He would also switch some of the chain's road freight (he did not say how much) to rail. But he said nothing about reducing the journeys made by his customers. Shopping accounts for 20% of car journeys in the UK, and 12% of the distance covered. By closing their out-of-town stores and replacing them with warehouses and deliveries, the supermarket chains could reduce the energy costs of their buildings and (according to government figures) cut the transport emissions caused by shopping by 70%.
Today, the Competition Commission publishes the initial results of its inquiry into the market dominance of the superstores. One of the issues it is investigating is the "land bank" accumulated by Tesco - a huge portfolio of sites on which the company appears to be sitting until it can obtain planning permission. Many of them are out of town. If Tesco develops them, it will drag even more cars on to the road. Out-of-town shopping is incompatible with sustainability.
So, perhaps, is the sheer scale of the business. Wal-Mart and Tesco can change the world at the stroke of a pen, but one decision they will not make voluntarily is to relax their grip on local economies. It will always be harder for small businesses to work with a global behemoth than with the local baker or butcher; Tesco's economy will continue to favour the big, distant supplier over the man down the road. And what of the sense of community that independent small shops help to foster, which encourages people to make their friends close to home? If love miles are the most intractable cause of climate change, we need to start cultivating as much community spirit as we can.
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http://environment.guardian.co.uk/climatechange/story/0,,1996687,00.html