The Green Mile

here's an interesting article on the ecology of food transportation, from a Deloitte publication.

Efficiency, not distance traveled, might hold the key to supply chain sustainability
by Lee Barter

“Life is difficult in the country,” observed English essayist Sydney Smith in 1855, “and it requires a good deal of forethought to steer the ship, when you are twelve miles from a lemon.” Plus ca change. One hundred and fifty years later it seems the distance between you and the twist in your next Bombay Sapphire is once again a going concern. Stressing the importance of minimizing “food miles”, the Slow Food movements in Europe and North America have made fast progress advising consumers to eschew globally-sourced supermarket wares in favor of locally raised produce from the farmer’s market. Food retailers have received the message and responded. Last fall, Whole Foods announced a plan to greatly expand the slate of local products on offer. European grocery giants, Tesco and Carrefour have also followed suit.

Why the turnabout? Have we traveled a bridge too far in pursuit of the perfect martini? More pressingly, can we draw meaningful conclusions about the environmental impacts of supply chains simply by peaking at the odometer?

The logic of food miles has an intuitive simplicity: the farther food travels from “field to fork,” the greater the associated environmental impact from transportation-related greenhouse gas (GHG) emissions. The stakes are significant; a recent study revealed 25 percent of heavy trucks on U.K. roads transport food. Meanwhile, Americans sit down nightly to dinners sourced from five countries, on average. The uneaten broccoli being scraped into Swedish trash cans was almost certainly shipped 12,000 miles from Ecuador before meeting its ignoble fate.
How can such a system possibly make sense? Surely any measure to reduce the distance food travels to market would be positive for the environment, no?

Perhaps, perhaps not. Filled with such deliciously titled figures as “Energy use in the life cycle of spaghetti” and “Greenhouse gas impacts [of] tomato ketchup”, the most recent report by the Department for Environment, Food and Rural Affairs (DEFRA), at Manchester Business School, turns up some surprising findings. For example, tomatoes sourced from Spain consume more energy from transportation than local tomatoes, but far less in aggregate, owing to the extra energy consumed by hothouses used to raise British tomatoes. The study also reported German apple juice imports from Brazil were less energy-consumptive than local production, despite traveling 10,000 more miles to reach the store shelf. For similar reasons, lamb from New Zealand was found to possess efficiencies versus locally raised meat. A pair of German researchers have even coined the term “ecologies of scale” to describe how mass supply chains can use size to offset the environmental penalties of distance.

Unaccounted-for transport efficiencies greatly reduce the usefulness of food miles as a proxy for sustainability. Considerations such as transportation mode (a container mile on water is roughly 50 times more energy efficient than a mile in the air) and load factor (a heavy transport truck running empty consumes 70 percent of the fuel required to move 25 tons of cargo), among myriad other complexities (emissions at high altitude cause far greater impacts than those at ground level) preclude such simple abstractions. Surprisingly, once these variables are accounted for, the most important transport leg in food supply chains is often the consumer’s commute to and from the grocery store or farmer’s market (in many cases exceeding the combined emissions for all preceding movements). Indeed, any environmental benefits obtained by purchasing local produce from the farmer’s market across town were quite likely nullified the moment you drove past the supermarket. This revelation produces an unexpected conclusion: it might be better to shop local than buy local.

However, as European regulators consider new legislation that could add food miles information to grocery labels, the relative efficiencies of transportation modes may get lost in the shuffle. From the perspective of the consumer trolling the supermarket aisle, it is hard enough to choose between great taste and less filling, without the added long division of air miles versus sea miles. Ultimately, as food miles labeling gains traction with consumers (and it appears this is happening) the onus will be on exporters and the transportation industry to come up with a simple, yet reliably accurate way to measure the environmental impacts of supply chains.
Deloitte Consulting supply chain guru, Chris Gopal, has noted that the shipping industry was late to the game in recognizing this need and is now scrambling to define standard measures for environmental performance. From Chris’ vantage point, the market for experts who can help companies measure and manage supply chain sustainability is teetering on the cusp of a vast and rapid expansion.

The Buy Local movement is freighted with unique social and political baggage (a good deal of it valid) that must be considered before applying the lessons of food miles in the broader context of supply chain sustainability. Not convinced? Simply look for similar “Buy Local” campaigns for toilet paper, for televisions, for blue jeans – they don’t exist (at least, not yet). Nevertheless, the food supply chain has been studied more than most and offers worthy insights about sustainability. The most important, albeit counterintuitive, lesson is that supply chain sustainability is not simply a function of distance. It is the most efficient, rather than the shortest, supply chains that are often the greenest.

The good news is that supply chain efficiency and environmental sustainability may have finally found common cause. High load factors and fuel efficiency are desirable both from a cost and per ton emissions standpoint. The cheapest modes of transport (ship and rail) also happen to consume less energy than more expensive channels (truck and air). This new thinking should come as welcome relief to supply chain managers facing tough new mandates to “green” their organization’s supply chains as the Al Gore Era steams into year three. The bad news is that it will be an uphill climb to accurately measure the environmental sustainability of supply chains and efficiently relay the message to consumers.

But perhaps there are alternatives we just haven’t conceived yet. Food kilometers? “Kilometers are shorter than miles,” comedian George Carlin notes, “Save gas, take your next trip in kilometers.”