Organic fruit from Chile, grass-fed lamb from New Zealand, spring water from Fiji, and plastic toys from China all have one thing in common: they require a lot of fuel to make and to move from source to market. Food travels an average of fifteen hundred miles before it reaches an American plate. That ecological footprint is usually hidden from the consumer, who may only think about fuel consumption when standing at the gas pump. Tesco, the largest supermarket chain in Britain and one of the top five retailers in the world, aims to change that.
As part of a twenty-point plan to address climate change, Tesco will begin “carbon labeling” all seventy thousand products on its shelves. A carbon label is a bit like the calorie information that appears on packaged food, but Tesco’s new labels will reveal the total amount of carbon dioxide created from the production, transport, and consumption of the goods it carries.
Tesco’s program will begin with a £5 million academic research study on methods for calculating the carbon content of retail goods. Carbon dioxide is the direct result of the consumption of energy, whether that energy comes in the form of gasoline to move trucks or electricity to power factories. Calculating the exact amount of CO2 embodied in an item on the shelf requires cataloguing all of the energy inputs required to make and transport that item — a vexingly complex task. The questions involved are difficult and potentially controversial. How much fertilizer is used to produce an ear of corn? How many tractors are needed to till the soil? How much energy for refrigeration? How much fuel for transport? Answers are even more complicated for factory-made goods.
It will likely take a good deal of time for consumers to get comfortable with carbon labels and figure out how to interpret them. Is it meaningful to compare the carbon content of a box of cake mix with a pair of pants? Which is better for the environment, an organic, high-carbon vegetable, or its conventional, low-carbon counterpart? Britain’s leading organic certification body, the Soil Association, may have already decided. At the end of January, the association announced that it might withhold its seal of approval from produce that is transported by air.