Energy Factoid: The world depends on fossil fuels

As detailed by polymath Vaclav Smil in his book "How the World Really Works."

I require my students to read one or more of Vaclov Smil’s 40 books. In “How the World Really Works,” Smil delves into several hot-button topics, arguing that:

“Understanding how the world really works cannot be done without at least a modicum of energy literacy.” (page 25)

Smil is not a cheerleader of fossil fuels, but he is a realist. A summary of a few of the energy realities Smil discusses follows (emphasis added).

Energy Factoid 1: Energy density is important.

“Most recently, a poor understanding of energy has the proponents of a new green world naively calling for a near-instant shift from abominable, polluting, and finite fossil fuels to superior, green and ever-renewable solar electricity. But liquid hydrocarbons refined from crude oil (gasoline, aviation kerosene, diesel fuel, residual heavy oil) have the highest energy densities of all commonly available fuels, and hence they are eminently suitable for energizing all modes of transportation.”

Energy Factoid 2: Feeding the world requires fossil fuels, especially diesel fuel.

“With diesel fuel containing 36.9 megajoules per liter, the typical energy cost of wheat from the Great Plains is almost exactly 100 milliliters (1 deciliter of 0.1 liters) of diesel fuel per kilogram—just a bit less than half of the US cup measurement. I will use specific volume equivalents of diesel fuel to label individual foodstuffs with the energy embedded in their production.

Bread: “Growing the grain, milling it, and baking a 1-kilogram sourdough loaf thus requires an energy input equivalent of at least 250 milliliters of diesel fuel, a volume slightly larger than the American measuring cup. For a standard baguette (250 grams), the embedded energy equivalent is about 2 tablespoons of diesel fuel.” (page 56)

Chicken: “The most conservative combined rate for feeding and rearing the birds would be thus an equivalent of about 200 milliliters of diesel fuel per kilogram of meat, but the values can go as high as 1 liter…The total energy requirement for putting a kilogram of roasted chicken on dinner plates (is) at least 300-350 milliliters of crude oil: a volume equal to almost half a bottle of wine.” (page 58)

Tomatoes: After many pages of detailed analyses of how modern tomatoes are grown in greenhouses and analyses of the energy contained in all the components, such as plastic sheeting that is derived from petroleum feedstocks, and the formulation of nitrogenous fertilizer, Smil concludes: “This means that when bought in a Scandinavian supermarket, tomatoes from Almeria’s heated plastic greenhouses have a stunningly high embedded production and energy cost… equivalent to about 650 Nk/kg, or more than five tablespoons of diesel fuel per medium-sized (125 gram) tomato!” (page 61)

Smil concludes: “…even if we try to change the global food system as fast as is realistically conceivable, we will be eating transformed fossil fuels, be it as loaves of bread or as fishes, for decades to come.” (page 75)

Energy Factoid 3: The four pillars of modern civilization are cement, steel, plastics, and ammonia and all depend on fossil fuels.

“While there can be no indisputable ordering of our material needs based on claims of their importance, I can offer a defensible ranking that considers their indispensability, ubiquity and the demand size. Four materials rank highest on this combined scale, and they form what I have called the four pillars of modern civilization: cement, steel, plastics, and ammonia” (page 77). Physically and chemically, these four materials are distinguished by an enormous diversity of properties and functions. But despite these differences in attributes and specific uses, they share more than their indispensability for the functioning of modern societies.” (page 77)

“Another key commonality between these four materials is particularly noteworthy as we contemplate the future without fossil carbon: the mass-scale production of all of them depends heavily on the combustion of fossil fuels, and some of these fuels also supply feedstocks for the synthesis of ammonia and for the production of plastics. Iron ore smelting in blast furnaces requires coke made from coal (and also natural gas); energy for cement production comes mostly from coal dust, petroleum coke, and heavy fuel oil. The vast majority of simple molecules that are bonded in long chains or branches to make plastics are derived from crude oils and natural gases. And in modern synthesis of ammonia, natural gas is both the source of hydrogen and processing energy.” (page 78)

These are just a few of the fossil fuel realities, according to Vaclav Smil.