There was an interesting piece in the Observer about Tesco being attacked for under-stating their carbon footprint by Christian Aid. The supermarket giant has come up with a figure of 4m tonnes CO2 equivalent per annum (more than Mauritius). Christian Aid say that if you include consumers driving to/from supermarkets and the activities of suppliers, Tesco’s footprint could be up to twelve times this.

This is a very interesting question: whose carbon is whose?

A consumer can choose whether to drive to an out of town supermarket, or cycle to their high street. On the other hand, the out of town shopping centre was a fundamental part of the ‘stack ’em high, sell ’em cheap’ business model that lead to the supermarket boom in the 1980s and the decline of independent high street shops. So does that carbon belong to the consumer or the supermarket? Do we halve it between them or double count it?

I think the supplier issue is more clear cut – the choice of produce is a clear choice of the supermarket buyers who have a legendarily iron grip on their supply chain. By making low carbon choices, Tesco could make a huge difference to the food industry (which translates into about a sixth of your own carbon footprint). But there still remains the issue of allocation – if Tesco admits responsibility for the emissions, does that let the supplier off the hook?

This problem scales up to the global level as well. The UK Government is keen to state that the UK’s carbon footprint is only 2% of the world’s total, but, as we outsource much of our manufacturing, agriculture and tourism to other parts of the world, is that the full picture? China may be building huge numbers of new power stations, but the average Joe in China is not driving a 4×4, or sitting under a patio heater, eating imported food – China is manufacturing products for the rest of the world, including us.

We urgently need better allocation methods to reflect both production and consumption, or we’ll never have a clear idea of where responsibility lies.

Note: apologies for the lack of posting on Friday – I had another great video for you, but ended up mired in sweary HTML hell. Will try to get it sorted for this week.