Unnoticed by perhaps 99.9 percent of the western population, a spat has broken out in the corner of the internet that is exercised with what we might broadly call “The Limits to Growth.” The row concerns something called EROI or EROEI – energy return on energy invested. This is an idea borrowed from biology by systems ecologist Charles A. S. Hall. Hall’s observation – well understood in biology – is that an organism must derive more energy from its environment than it requires in order just to stay alive. This is because it also requires the energy to procreate and, mostly in mammalian species, to rear the next generation.
Hall’s contribution to our understanding of the human economy is that a similar balance between energy-in and energy-out must also occur. To operate something as complex as a modern medical service or the plethora of arts and entertainment activities, we must generate a surplus of “exergy” – the energy available to do work – over and above the energy required to keep us all alive. EROI in this respect, was a tool to help us think about the role of energy in the human economy. It was never intended that we should, for example, attempt to calculate the EROI difference between white and wholemeal bread as a human energy source. But what it did tell us was that if our civilisation’s EROI were to fall below a certain level, we would hit a “net energy cliff” which would cause much of the developed, non-energy economy to unravel:
So far, so good. Except that Hall’s work arrived on the scene just as the first wave of the peak oil movement – led by former oil industry insiders such as Colin Campbell and Matthew Simmons – was drawing attention to the likely consequences of the world’s big – and relatively cheap – oil fields beginning to decline. The giant Ghawar field in Saudi Arabia, for example – the biggest ever – was discovered in 1948, and by the 1990s, was expected to soon be in decline, along with much of the Middle East’s oil (Continental US conventional oil having peaked in 1970). Moreover, the volume of oil being discovered by then was but a fraction of those earlier discoveries. Worse still, the global economy was consuming around four barrels for every new barrel discovered, with the demand for economic growth causing the gap to widen with each passing year.
The concept of EROI fed into peak oil concerns by showing that there was likely to be a lower energetic boundary to further oil extraction. At its simplest, if a new oil field was so difficult to drill that it would cost one barrel of oil to get one barrel in return, then nobody in their right mind would do so. As Hall was to put it, at an EROI of 1:1, all you get to do with that oil is look at it. As with biology though, we require much more exergy than that needed merely to keep us alive. And an oil-based economy doesn’t really function with oil, but with oil products – if you don’t believe me, try putting crude oil in your car’s fuel tank and see how far you get. Hall reckoned that two thirds of the energy from oil (EROI 3:1) would be lost in the process that moved it to, and through, the refineries. More again would be lost transporting products like petrol from the refinery to the filling station… and a bit more to pump it into your car. And as you drove your car away after filling up, some 60-70 percent of the energy contained in the petrol would be wasted as heat, leaving just a third for useful work.
It is at this point though, that the concept of EROI exceeds its useful purpose – which was merely to point out that a complex oil-powered economy like the USA – or, indeed, the global economy as a whole – needs massive amounts of energy to avoid a collapse… and even more to maintain the desired infinite growth which is central to our monetary system and our economic models. When it comes to individual energy sources, economic complexity makes attempts to calculate EROI akin to medieval scholars attempting to determine how many angels can dance on the head of a pin. There is no EROI for a barrel of oil because barrels of oil are not equal. Light tight oil from the Permian Basin will have a lower EROI than heavy Ural crude – but there’s no real value in trying to work out the exact numbers… not least because the EROI provided to the economy will also be affected by where and how that oil is refined. The same, of course, goes for wind turbines and solar panels – where they are made, how far and by what means they are transported, and where they are deployed is far more important for determining the EROI.
Unfortunately, following considerable criticism of the prevailing “eco-modernist” version of “net zero” proposed by corporations like Vanguard and Black Rock, which was not based on EROI, the proponents of non-renewable renewable energy-harvesting technologies (NRREHTs) have responded by claiming that the latest generation of wind turbines have a high enough EROI to invalidate criticisms which are primarily based upon the unavailability of the material resources needed to build the proposed NRREHTs infrastructure. Put simply, if the latest wind turbines and solar panels are twice as powerful, then we only need half the resources to make and maintain them. Although, given the need for 189 years’ worth of copper, the 400 years of Nickel or the 9,920 years of Lithium that are needed to dispense with fossil fuels, NRREHTs are going to have to increase their power exponentially between now and the arbitrary 2050 cut off point.
In any case, Moore’s Law-type claims of ever rising EROI are implausible, because – with the temporary exception of relays on a computer chip – that isn’t how productivity improvement works. Rather, technologies follow an “S” curve in which a series of cheap and easy improvements at the beginning of a technology’s life result in big productivity improvements, but once these have been achieved, improvements become ever more expensive and difficult. And in the case of energy-generating technologies, thermodynamic limits like Betz Law (wind) and the Shockley-Quiesser limit (solar) place a physical upper limit on the energy that can be generated by these technologies irrespective of how much we spend trying to improve them. Moreover, the closer to the limit we might get – for example, using ultra-powerful magnets and high-quality lubricants in turbines – the more (energy) expensive the technology becomes.
It goes without saying that nobody has actually tested the EROI of a solar panel or a barrel of oil. Instead, the proponents of the various energy technologies merely model the potential energy which might be produced. Unfortunately, as we have seen in economics, public health and meteorology, modelling of this kind is invariably clouded by the unconscious biases of those constructing them. If, for example, one wanted to promote the potential benefits of covering the desert with solar panels, one’s model might omit such things as the build-up of dust over time, the likely loss of energy in transmission, the cost of shipping the panels from China or the energy required to mine and transport the lithium to produce the batteries needed to store excess electricity when it arrives at the point of use.
This is why I can only wish that we had access to an island where we might construct the first generation of an entirely renewable economy. This would not only include the NRREHTs for generating the electricity, but also the battery storage and the factory to construct the next generation. It would also have to be a large enough island to provide the accommodation and food for the population required to work in the NRREHTs factory. But beyond this, the islanders would not be allowed to cheat by drawing upon imports from the broader, fossil fuel-based economy, since this would invalidate any claim that these technologies are renewable or that they can provide all of the energy to sustain the economy. As The Honest Sorcerer puts it:
“If we were truly serious proving that it is indeed so, and that there is an industrial civilization after fossil fuels, we would be funding and building solar projects encompassing the entire supply chain of photovoltaic panels manufacturing: all powered by “renewable” energy. At least on a small scale.
“We would be building a set of experimental mines, copper refineries, smelters, and plants manufacturing and recycling those panels — all powered by ‘renewables.’ We would then be able to assess realistic energy and material requirements, experiment with the necessary technologies to circumvent intermittency and see if our recycling rates are good enough. Who knows, we might even see if it is possible to maintain this high energy lifestyle based on ‘renewables’ alone.”
It goes without saying that nothing even remotely like this has been done. This is because at our current level of physics, chemistry, and engineering it is entirely beyond us. Without the plastics derived from oil and gas, there are no wind turbine blades and there is no insulation for the thousands of miles of electrical wires and cables. Without temperatures far higher than those obtained from NRREHTs there is no concrete with which to secure the NRREHTs technologies in place. Without the high temperatures provided by burning gas, there are no pure silicon wafers and there is none of the specialist glass used in solar panels. Without heavy oil fuels, the massive opencast mines and mineral production plants spread out across the global economy could not supply essential metals like copper, nickel and a host of rare earths. And without a network of oil fuel-powered ships and trucks, none of those metals could be transported from the mines to the NRREHTs factories. To put it another way, without the backing of an advanced and globalised oil-based economy, the EROI of NRREHTs falls to zero.
Less obviously – a point made in a recent Great Simplification discussion – we have wasted the energy and mental skills of many of our best scientific and engineering minds pursuing a “bright green” mirage, when they might have been allowed to engage in the kind of disruptive and innovative research that might otherwise have saved the day… which brings me to the other island that I think we should establish – the one where we put all of the politicians, corporate CEOs, think-tankers and banksters who made the decision to take us down this impossible road in the first place. This is the island where the fossil fuels are no longer available and the NRREHTs have broken down for lack of maintenance. It is the island where those who survive will have to learn the kind of coping skills last employed in Anglo-Saxon England. Because the real immorality of the corporate-sponsored pretence that exhausting what remains of planet Earth on an impossible NRREHTs infrastructure, is that another ‘dark age’ – akin to the 500 years between the collapse of Rome and the arrival of the Normans – is precisely what they have inflicted on everyone else.
As you made it to the end…
you might consider supporting The Consciousness of Sheep. There are six ways in which you could help me continue my work. First – and easiest by far – please share and like this article on social media. Second follow my page on Facebook. Third follow my channel on YouTube. Fourth, sign up for my monthly e-mail digest to ensure you do not miss my posts, and to stay up to date with news about Energy, Environment and Economy more broadly. Fifth, if you enjoy reading my work and feel able, please leave a tip. Sixth, buy one or more of my publications