The Crash Course - Chris Martenson [73]
Figure 15.5 The Energy Cliff (4): Net Energy from Renewables
Not all energy forms are fully comparable on the basis of net energy returned. Solar and wind do not produce liquid fuels.
If we add in all the other new usable liquid fuel sources that we’ve just talked about, we see that they’re all somewhere “on the face of the energy cliff.” Solar and wind16 are both capable of producing pretty high net returns, but it’s important to note that these produce electricity, not liquid fuels, which means that they are not at all comparable. Peak Oil represents “peak liquid fuels,” and that’s the primary issue here for petroleum. Once we get to Peak Coal (and we someday will), or begin to operate our transportation infrastructure on electricity, then electricity from the sun is more directly applicable to meeting our needs and solving our challenges. If we were to try and make a go of it on corn-based ethanol alone, this is the world in which we’d (be trying to) live:
There’s no gray zone to speak of left in that chart, and practically no surplus at all to fund even the basics of life, let alone a rich, complex economy full of prosperity and opportunities.
Unless we very rapidly find ways of boosting the net energy of the remaining energy options, we’ll simply find that we have far less surplus energy to dedicate to our basic needs and discretionary wants than we came to expect and enjoy from fossil fuels. We’ll be using far too much energy in the essential, mandatory practice of finding and producing more energy, and we’ll find ourselves with far too little left over to use as we wish. Our energy investment costs will skyrocket even as the returns dwindle. That’s just the basic reality of the situation; it’s not possible to fool nature with fraudulent accounting.
Oh, and where’s the so-called “hydrogen economy” in Figure 15.6? It’s below the x-axis in negative territory, meaning that it’s not a viable candidate around which to fashion a society. It’s negative because it has to be produced from other forms of energy—perhaps electricity (via hydrolysis) or from natural gas. Because there are no hydrogen reservoirs anywhere on earth, every single bit of it has to be created from some other source of energy—and, here’s the kicker, always at an energy loss. In other words, hydrogen is an energy sink, not a source; its tiny bubble would have to be placed below the zero percent mark on the above chart. In creating hydrogen, we lose energy. That’s not pessimism; that’s the law—the second law of thermodynamics, to be exact. We’ll talk more about the laws of thermodynamics in Chapter 18 (Why Technology Can’t Fix This).
Figure 15.6 The Energy Cliff (5): Trying to Live on Alcohol Alone
The Economy and Energy
A massive abundance of surplus energy, liberated by the lightning bolt of humanity, has enabled historically unparalleled levels of prosperity to be enjoyed by billions of people. But respect for the role of energy in providing this abundance has largely gone missing from the economics profession, which will prove to be a rather tragic mistake. It’s somewhat odd that it has been thus ignored, because the evidence for the connection between growth in energy utilization and economic growth (and prosperity) is extremely well documented and also intuitively obvious (Figure 15.7).
Figure 15.7 Energy Consumption and GDP in the United States
Source: Energy Information Administration & Bureau of Economic Analysis.
Even less well appreciated is the degree to which economic complexity owes its existence not just to the total amount of energy being utilized, but to the net free energy that flows through society. Out of all the sources of energy, petroleum stands out as the most important of them all, due largely to its presence in nearly every consumer product that is made, transported, and sold. Oil is richly woven into our economic tapestry, and there are