för naturens skull

"Back when our food came from the family farm down the road, a farmer got about three calories of food back for every calorie of work he invested in his land. Today, now that the work is done by gigantic diesel-powered tractors and combines and trucks, we get one calorie back for every ten invested. Like the Canadian oil sands, this is another example of a diminishing energy rate of return. And that diminishing energy rate of return just gets more daunting with every rise in the price of oil."

 

(Jeff Rubin i boken "Why your world is about to get a whole lot smaller", 2009)