06/30/2016 12:17 pm ET Updated Jul 01, 2017

Local Food Won't Save The Planet

We are all concerned about the environment and about what life will be like for generations yet unborn. So the idea of local sourcing is becoming very popular, particularly in respect to organically grown food.

Intuitively Obvious but Practically Wrong
The notion of local sourcing seems to make sense. After all, it should require less energy to grow food locally in small quantities than to ship it in from distant states, or countries.

Yet, there are two variables in the energy equation that are not given due consideration. The first is that small-scale production in local market gardens is extremely inefficient in the sense that a great deal of energy is required per unit of harvested crop. The second is that modern transportation is extremely efficient so that bringing in a bag of apples from New Zealand costs a trivial amount of energy and if it didn't, New Zealand apples could hardly be sold here.

The simple economics of distant trade since the industrial Revolution has always suggested that moving goods around the world is not as futile as it might appear. So the British could bring in raw cotton from countries as distant as India, or the US, and produce cloth and garments cheaply enough to compete with locally made goods.

Gonna Build a Toaster
Large corporations build household items like toasters with fantastic efficiency thanks to the wonders of capitalist competition and resulting efficiency.

The inherent flaws in the local sourcing argument are illustrated by an amusing experiment in which artist Thomas Thwaites made his own toaster rather than buying it for the equivalent of less $10 in an English supermarket. He found it extremely difficult to get the necessary raw materials, copper, iron, plastic, and mica (an insulator). The project took several months, cost a lot of money and yielded an inferior product .

Similarly, Kelly Cobb of Drexel University decided to produce a man's suit from materials acquired within 100 miles of her home. She found that it took 20 craftsmen a total of 500 hours to make the suit that ended up costing about a hundred times more than the regularly produced item.

There is a cautionary tale built into this episode, when you produce something locally, you may save money on transportation, but this does not mean that the product is going to be efficiently produced or good for the environment. This fallacy is deeply embedded in the grow-local movement for food.

Why Local Food Is Not Green
When economists studied the energy costs of producing food, they found that the whole concept of "food miles" is deeply flawed as a sustainability indicator.
According to English writer Matt Ridley (pp. 41-42):

Getting food from the farmer to the shop costs just 4 percent of all its lifetime emissions. Ten times as much carbon is emitted in refrigerating British food as in air-freighting it from abroad, and fifty times as much is emitted by the customer traveling to the shops. A New Zealand lamb, shipped to England, requires one-quarter as much carbon to get on a London plate as a Welsh lamb; a Dutch rose grown in a heated greenhouse and sold in London, has six times the carbon footprint of a Kenyan rose grown under the sun using water recycled through a fish farm, using geothermal electricity and providing employment to Kenyan women.

Save Yourself, Not the Planet! Growing food locally makes very little sense from either an environmental or an economic perspective. Yet there is a good argument for growing food locally that is much more experiential than economic, or environmental. Nothing tastes better than garden produce straight out of the earth, or off the vine.

Even more important, the gardener feels a deep connection with the natural world unlike any other, monitoring the progress of each plant from one day to the next.

The physical activity of working in a vegetable plot is very good for cardiovascular health. The psychological benefits are even more impressive. Gardening is likely to elevate a person's mood because it is forward-looking, active, nurturant, and productive. Growing one's own food gives a person a great sense of control over one aspect of their lives. Perhaps for these reasons, gardening programs in prisons are among the most effective ways of rehabilitating career criminals.

If you want to grow your own vegetables, do it to save yourself. You are not saving the planet.