The Grand Challenge of the Energy Transition

IntroductIon Energy is the key factor that drives the economy. Without abundant energy coming from sources other than human and animal muscles, the society as we know it would be unthinkable. Energy is needed to power all kinds of machinery, but also for the vital task of supplying the industrial system with the mineral commodities that make it function. Energy is also fundamental for the food production system which can sustain billions of people only because it makes large use of energy coming from outside agricultural sources (Giampietro, 2002). The first to realize the importance of energy for modern society was probably William Stanley Jevons, who wrote in his “The Coal Question” (Jevons, 1866) that: “Coal in truth stands not beside but entirely above all other commodities. It is the material energy of the country — the universal aid — the factor in everything we do. With coal almost any feat is possible or easy; without it we are thrown back into the laborious poverty of early times.” Today, we can substitute the term “fossil fuels” for “coal” in Jevons’ statement and obtain a good description of our situation. Our society is based on fossil fuels and for many purposes – such as for transportation – there exist no comparable energy sources that could drive the existing infrastructures. Without fossil fuels we would indeed be thrown back into the “laborious poverty” of old times. The question that Jevons was asking in his 1866 study was “how long can coal sustain the British industry?” The same question can be asked today about fossil fuels and the world industry. The answer cannot be any other than: “not forever” since, for all practical purposes, the amount of fossil fuels available to humankind is finite. But, just as Jevons had argued for coal, the problem is not the physical running out of fossil fuels; it is the fact that we are gradually running out of the low cost resources that had been used to build up our industrial system. As a consequence, the industry is forced to extract fuels at increasingly higher costs from resources which are deeper, more remote, less practical, and in general of lower quality. As a consequence, we need to invest increasing amounts of energy to obtain the same amounts of energy as in earlier times. This problem is normally defined in terms of a parameter termed “energy return of energy investment” EROI or EROEI (Murphy and Hall, 2011) which, for fossil fuels, declines as a function of the extracted quantities (Bardi et al., 2011). The result is the generalized increase of energy costs experienced during the past decade or so; an increase that has interrupted a decreasing trend that had been lasting for more than a century (Fouquet, 2011). At the same time, the Earth’s capability of absorbing the products of the combustion of fossil fuels is limited. As this text is being written, the concentration of carbon dioxide in the atmosphere has reached 400 ppm (Sweet, 2013); a value not known to have ever existed during the past few million years. In addition to the heating of the atmosphere generated by the greenhouse effect, there are several negative consequences of this increasing CO2 concentration: ocean acidification, sea level rise, extreme weather phenomena, and more. Possibly the most worrisome of these effects is the release of a more potent greenhouse gases: the methane trapped in the Northern Permafrost and in deep-sea hydrates. This event would then further accelerate the negative trends with truly catastrophic effects (Archer, 2007). At present, we cannot determine whether warming or depletion is the more important problem we are facing, but we know that both are caused by our dependency on fossil fuels. As a consequence, it is imperative to reduce, and eventually eliminate, this dependency before it is too late. Given the situation, it is hard to think of a grander challenge for humankind than that of creating a society that can function without fossil fuels and at the same time maintain a level of prosperity and complexity comparable to the present one – and creating it in relatively short times. How are we going to meet this challenge? Whatever we decide to do, the transition is already in progress.