A scale to classify extraterrestrial civilizations reveals the necessity of rethinking energy and planetarity on Earth.
Energy, Civilization & Planetarity
Narratives of “degrowth” or “sustainability” suggest that human civilization will need to use less energy in the future. But what if instead, the trend is heading in exactly the opposite direction, on a trajectory of ever-increasing energy use?
At some point, we would enter the near-fantastical levels of energy usage envisaged by the Kardashev scale—a theoretical means of classifying civilizations proposed by the Soviet astrophysicist in 1964 as part of the search for extraterrestrial intelligence.
Given that we have not found any evidence of such extraterrestrials, we propose repurposing the Kardashev scale to assess what planetary civilization means here on Earth.
In that context, we ask: Where are we on the scale, and what does that say about our level of advancement? What might be the thermodynamic and civilizational consequences of advancement on the Kardashev scale? What is the scope of our agency as we head towards many possible futures, and what might those futures look like? And finally, working backwards from them, what might we learn about inhabitation of Earth during our current anthropogenic crisis of energy metabolism?
Let’s start with Earth—as a planet, not an experiential “world” or a hollow “globe.” A planet of spheres. From the surface, inwards through the lithosphere and the asthenosphere into the mesosphere’s mantle and core. Not just deeper inwards, but deeper outwards through the geosphere, pedosphere, biosphere. We explicitly include the technosphere, the sum of all humans, our technology, institutions, and infrastructure—all thirty trillion tons of it. Highways, AirPods, sewers, art, landfills, science, cities. Outwards, not just to the edge of the stratosphere, but further extending the planetary boundaries past the Karman line demarcating space to the orbiting cloud of satellites and techno junk.
Having found a tentative and temporary boundary, where do we situate this planetarity? What is the final and correct vantage point? None, or rather, all of them. Every angle, at every size, at every time-scale—geological, chemical, biological. Subatomic particles rushing around the Large Hadron Collider, smashing into each other, the results disappearing in a zeptosecond—an answer just long enough to suggest a different question. The whole planet seen by the Cassini probe, Earth as a tiny white-blue dot that barely appears—let alone smiles. And from the planet itself, newly arranged into a camera, taking its first-ever picture—of a black hole.
The Terraforming is a comprehensive project to fundamentally transform Earth’s cities, technologies, and ecosystems. Of course, the Anthropocene—imagine whichever text you like here, qualifying or problematizing or doubling down on the term—reveals our ongoing, headless, irrational, unethical terraforming project. That is to say, the technical means to terraform—particularly in relation to the climate—clearly already exist.
While to date this has been partial and unintentional, the consequences are widespread and meaningful. But what if we imagined a future version of the planet that spawned a civilization for whom the complete ordering and reordering of its physical state was not just a theoretical possibility, but a material reality?
That would be a planet that makes a civilization, which in turn remakes the planet.
One absolute requirement for such a planetary civilization would be the ability to command immense amounts of energy, which is key to how its level of advancement might be classified, and indeed how it might even be detected by a listener across the vastness of space.
To make sense of such a future involves returning to the past.
In 1964, Soviet astrophysicist Nikolai Kardashev proposed a scale to classify technologically developed civilizations. This was part of the search for extraterrestrial intelligence, and as such the key consideration was detectability; to find something, we need to first decide what to look for. Even the nearest stars are extremely far away, and space is full of background noise. The transmission of an extraterrestrial information signal detectable on Earth would require huge amounts of energy, and therefore could only be sent by a highly developed technological civilization.
So Kardashev proposed three levels of civilization based on energy. According to his initial classification, a Type I civilization represented a technological level and energy consumption close to that then (in 1964) attained on Earth, roughly 4×10¹² Watts. A Type II civilization would be capable of harnessing the energy radiated by its own star, around 4×10²⁶ Watts; and a Type III civilization would be in possession of energy on the scale of its own galaxy, 4×10³⁷ Watts.
This original scale has been updated and redefined along the way, perhaps most notably by Carl Sagan in 1973. In The Cosmic Connection: An Extraterrestrial Perspective, he proposed redefining the energy values of the three types and switching from Roman numerals to decimal numbers, resulting in a logarithmic scale on which intermediate values could also be calculated. Type 1 was defined as 10¹⁶ Watts, Type 2 as 10²⁶ Watts, and Type 3 as 10⁶³ Watts. This also had the effect of “downgrading” the 1973 human civilization to roughly 0.7 on the scale.
For the purposes of our research, we define the scale as follows:
Type 1: a planetary civilization manipulating the energy resources of its home planet, an equivalent to the solar insolation on Earth, circa 1.74×10¹⁷ Watts.
Type 2: a stellar civilization capable of utilizing and channeling the entire radiation output of its star, in the case of the Sun about 4×10²⁶ Watts.
Type 3: A galactic civilization with access to the power comparable to the luminosity of the entire galaxy, in the case of the Milky Way galaxy about 4×10³⁷ Watts.
This generally follows the schema set out by astronomer Guillermo A. Lemarchand, but with a more accurate value for solar insolation on Earth to seek to reflect the now conventional concept that a Type 1 civilization would be able to control all the energy available on its planet. In our view, total solar energy received at Earth’s upper atmosphere constitutes the “true” value for the energy resources of Earth. Consequently, a Type 1 civilization—K1—would be something far beyond Kardashev’s original conception.
Carl Sagan also suggested using the letters of the English alphabet to describe total informational capacity, with each letter indicating a scale of magnitude in the number of bits stored. Defining letter A as 10²⁶, Earth of 1972 would have been roughly at level H. According to Sagan, there would not have been enough time since the big bang for any civilization to have reached level Z.
Recognizing that waste, particularly direct heating from out of control energy growth, may destroy a civilization, physicist and popular futurist Michio Kaku suggested in 2011 that the scale should take efficiency, waste heat, and pollution into account. While entropy overall always increases according to the second law of thermodynamics, civilization can be judged partially by its capability to limit the rate of growth of its local planetary entropy through increased efficiency and reduced waste and heat.
In 1999, John D. Barrow proposed a scale of civilizational types based on the ability to control matter at different microscales, from Type I-minus (manipulation of objects only of their own scale) all the way to Type I-Ω (control of the structure of space and time). Earth civilization was at that point roughly Type V-minus on Barrow’s scale, able to somewhat manipulate and engineer the atomic nucleus. Inverting the usual bias towards growth, this scale also has the benefit of imagining technical development proceeding inwards rather than outwards, as usually assumed.
Csaba Kecskés has sought to introduce more complexity to the concept of “advancedness,” through a detailed four-level scale based on factors such as long-range transportation capability (planetary surface to intergalactic); use of material and energy resources; and biological advancement including lifespan.
In our own research, we have looked at the above parameters and various other factors, including power density, energy budget, energy rationing or conservation, and private division or public accumulation to name only a few. All of these can be regulated by mechanisms and institutions like the market, ideology, infrastructure, or ethics.
Points on a scale
So where are we now? Human civilization as of 2018 was producing around 18.4 Terawatts of power, placing us at just over 0.6 on the Kardashev scale as we’ve defined it (≈0.73 on Sagan’s version). The scale is logarithmic, and as such while 0.6 may appear close, K1 energy consumption would be around 9,450 times higher than current levels. That is a phenomenal amount of energy. Let’s put it in perspective.
Given that our 2018 figure is only around 28 times more than that of 1800—a world of around one billion humans, where the most advanced technology was James Watt’s steam engine—it’s clear that four orders of magnitude is a difference so large that it’s difficult to overstate. In fact, finding a point in the planet’s history where the totality of human civilization commanded four orders of magnitude less power than today is literally impossible. When humans collectively metabolized 10,000 times less energy was certainly before the neolithic (agrarian) revolution which began circa 10,000 BC, writes Yadvinder Malhi. This was a time when we were hunter-gatherers whose most advanced technology comprised a sharpened stone. Civilization, as we commonly define it, simply did not exist.
So extrapolating the other way—from now to Kardashev Type 1—shows us that from today’s perspective such a civilization would command a staggering amount of energy. Its technology, and therefore its society and culture, would likely be so unfamiliar as to be impossible for us to properly comprehend.
“...the increase in power consumption of human civilization has been exponential, at least during the last two centuries, so any reasonable projection at timescales negligible in astrophysical terms will lead us very soon to the Type 1 and subsequently—barring a global catastrophe—to the 1.x status.”
Just like the Kardashev scale itself, historical energy growth rates have been exponential. If this trend continues into the future, there will be significantly less than 12,000 years between us and the K1 civilization.
In fact, taking the average annual growth rate of world power consumption over the past 165 years (2.6%) and projecting it into the future, we would reach a Kardashev Type 1 civilization in around 2370. Using a more conservative growth rate—the slightly lower 2% level since 1975—K1 would be attained in 2470. The point here is not to predict the year in which we become K1, but rather to demonstrate that getting there eventually is inevitable as long as the growth rate stays positive.
The feasibility of producing such a huge amount of power relies on continuing a similar rate of technological progress that took us to this point. This could involve fairly exotic space-based solar mirror arrays or anti-matter generators. But equally, if we successfully harness nuclear fusion—the same energy source that powers the sun—that would provide more than enough energy to reach K1.
Of course historical growth rates relating to technological ability and energy consumption do not prove that future growth rates will remain permanently above zero, on an inexorable upwards trajectory towards K1. But there may well be ongoing underlying factors driving such a pathway. Factors we don’t even control.
One of these relates to the technosphere. This complex planetary mega-system of technology, institutions, and humans—effectively every element of civilization, including humans merely as subcomponents—is considered by scientist Peter K. Haff, who coined the term, as an emerging autonomous global paradigm beyond our control or detailed understanding. Put simply, our civilization is a gigantic machine with its own logic. While currently reliant on humans to keep it functioning, it is too large and complex for us to fully direct.
Haff refers to the principle of maximum entropy production (MaxEP), which “asserts that sufficiently complex dynamic systems will evolve to a state in which usable energy is consumed as fast as possible, consistent with extant constraints.” Key concepts of non-equilibrium thermodynamics are difficult to precisely define and generalize, and as such MaxEP may not be falsifiable. It has, however, been used to successfully describe and predict complex Earth systems and as such may be better considered a powerful explanatory tool—a widely applicable method of inference rather than a physical law, according to Dyke and Kleidon.
“If a state of higher energy consumption can potentially be realized, that is, if there are no constraints that prohibit a faster rate of energy consumption, then [MaxEP] suggests that the technosphere will tend to evolve towards increased appropriation of usable energy, bearing its human parts along in the process.”
So what are possible constraints? For Peter Haff, the key concept is human acquisitiveness. He suggests that if the inclination to acquire is not eventually saturated, energy growth simply continues. So while humans might not be in full control of the technosphere, our desire to obtain more and more goods and services is what ultimately drives its growth.
It may be a structural, or infrastructural, question. Perhaps civilization will act as a bulwark, a limiting force against our more destructive innate urges. The track record of the existing “globalized” society is of course rather poor in this regard. Through capitalism, civilization in fact institutionalizes greed and insists, against the odds, on eternal growth fueled by unappeasable demand.
The best candidate is likely to be environmental (physical, chemical) constraints. So far, technology has come to the rescue, allowing us to avoid apparent environmental constraints. The most famous example relates to Thomas Malthus’ prediction that humanity was heading towards collapse as a consequence of exponential population growth colliding with linear food production increases. The credit for such a collapse being avoided lies largely with technological developments, in particular the Haber-Bosch process, currently responsible for half of all human food agriculture.
As the discussion of the technosphere strongly suggests, we are likely not in control of technology or its development on a civilizational scale. No person, no government or institution, in fact, is in a position to permanently switch off the power grid or stop research into nuclear fusion or space-based solar arrays. This may be due to the sheer scale and complexity of the technosphere, and the attendant impossibility of direct interface with any functional control surface.
Whether desire can reach such a saturation point could also be a primarily biological question. Will a fundamental drive—formed across evolutionary timescales when scarcity was the norm and temporary abundance would be fully exploited—at one point find its natural maximum and level off?
This leads us on to a slightly different suggestion: that beyond practical matters or systems theory, in technology we have simply revealed a force much older and much greater than us, with its own inescapable logic.
“The obsolete psychological category of ‘greed’ privatizes and moralizes addiction, as if the profit-seeking tropism of a transnational capitalism propagating itself through epidemic consumerism were intelligible in terms of personal subjective traits. Wanting more is the index of interlock with cyberpositive machinic processes, and not the expression of private idiosyncrasy.”
In this reading, human greed is not a “human” trait at all. Rather, it is an unavoidable, inevitable expression of machinic desire, of technocapital, of processes of expansion and consumption that started before we existed. Humans are vectors of those processes, not agents. We’re simply along for the ride.
In other words, it may be the case that we are not in control of the factors driving ever-increasing energy consumption.
If ascending the Kardashev scale is a goal (and it is for some), its inevitability might seem desirable and exciting. But it’s not the case that an upwards trend guarantees a safe landing. If humans are being carried along an exponential trajectory of more and more energy production, there is a risk of collapse along the way. We might see climate change now as an example of that phenomenon: energy consumption has increased exponentially, while the associated waste—principally CO2—has accumulated to a point where both the biosphere and technosphere face severe consequences.
A civilization approaching K1 would face a form of climate change on an even greater scale.
“Elementary thermodynamics and energy balance dictates that energy cannot be created nor destroyed. If we consider a ‘steady state’ scenario wherein we assume most energy acquired is not stored over very long periods of time (see, e.g., Wright 2014b), then the energy we use is inevitably released as thermal infrared energy into the biosphere and radiated into space. It is not an issue of energy efficiency, but a matter applying the conservation of energy over the entire Earth system.”
Before the heat is released into space it warms the surface of the planet, in an effect known as direct heating. This form of climate change is currently negligible compared to the impacts of greenhouse gases, but would drastically increase as energy use approaches K1 levels.
A few degrees of global warming might yet prove catastrophic for the biosphere and human society. With direct heating, Mullan and Haqq-Misra predict that we would face a “doomsday” event of 12˚C warming before we even reach K1. While this might not represent the end of days, it would be “a time limit by which transformative changes in population growth, energy use, and/or some other structuring of civilization are required to ensure survival.”
If humanity relies only on non-solar sources of energy such as fossil fuels, nuclear, and biomass, a direct heating doomsday would occur at around 10¹⁶ W of total power consumption. If instead we exclusively relied on solar power, our total output could be higher before doomsday is reached, but it’d still be before K1. Either way, as civilization on Earth starts to reach these types of energy levels, the only way of preventing such a direct heating doomsday scenario is by leveling off or reducing that usage.
But if increases are inevitable, what could be done? A civilization facing such a scenario could opt to use a significant proportion of its energy outside of Earth’s atmosphere. This important dilemma gives us the first parameter to analyze how different possible K1 civilizations might be: where do they generate and use the majority of their energy—on Earth, or in space?
And as we’ve seen, the second important factor would be the way in which civilization produces energy, as this affects the direct heating timeline—if it optimizes the surface of the planet mostly for solar energy absorption, covering it with photovoltaic elements and excluding other uses (labeled black in the diagram above), or if instead it uses other sources like fusion or solar power satellites and leaves some of Earth’s surface free (labeled blue).
Based on these variables we speculated on many possible scenarios for a future K1 Earth civilization. To get a sense of the contrasts, we set out the results of the more extreme versions on the Backcasting Kardashev One website.
They represent only four K1 scenarios, based on two primary variables—the type of energy production and the location of its consumption—combined with a limited set of secondary variables such as population and land use. Even so, they result in radically different potential K1 futures.
And there are, of course, many more possibilities—both for those futures and the pathways leading there. To explore these pathways we backcasted from each of the scenarios, tracing the chain of events in reverse to build one detailed but tentative timeline of how each of these scenarios could come about. In doing that, we connect them to where we are now.
The Kardashev scale was invented in the search for extraterrestrial civilizations—aliens consuming the energy of galaxies. But we still have no idea whether such intelligences exist, or what they might value or plan. So perhaps it was never about other civilizations, but about us. Not us as humans, per se, but as the planetary civilization that invented this scale, imagining the future after billions of years of automated planetary processes left us with that capability.
Moreover, it’s meant to be a scale about civilizational advancement. Let’s look at ourselves, not even a one on the scale, and recognize that we are not as advanced as we might sometimes imagine. Indeed, developing incredible technology or using godlike amounts of energy might not make us advanced either. As we make clear in the scenarios depicted on our website, other factors matter; not least, the thermodynamic, metabolic flows involved.
K1 might not even be our choice. We may be carried along an exponential trajectory by forces we don’t control, risking collapse all along the way.
Direct heating shows that physics and chemistry will get us in the end, but we already knew that. Sooner or later, climate change requires a deep look into what it would mean to be advanced. And reveals the necessity to respond to this anthropogenic climate change with an equally artificial planetarity.
That is to say, a planet that makes a civilization that remakes a planet.
It must do so first by imagining its end state.
In other words, a plan.
Backcasting Kardashev One is taking part in the exhibition RATAN 21.33, which opens on April 16 in the Special Astrophysical Observatory of the Russian Academy of Science in the village of Nizhniy Arkhyz, Karachay-Cherkess Republic. The show addresses the theme of life and the afterlife of the world's largest radio telescope, RATAN-600, which was developed and created with the active involvement of Nikolai Kardashev. The exhibition is organized by Gogova Foundation and curated by Daria Kravchuk and Nicolay Boyadjiev.