Becoming a Kardashev Type I Civilization

in 1964 Nikolai Kardashev reasoned that the most fundamental way to classify how advanced a civilization was was based on his energy consumption the more energy they consume which means control then the more sophisticated the civilization must be kadesha have even proposed a scale for quantifying how advanced civilizations are he could a civilization type one if it was able to harness all of the energy striking its planet from the parent star which for the earth is about one point seven times ten to the seventeen watts such a civilization should have complete control of their planetary environment weather and resources as well as their local orbit going further a type two civilization would have a power consumption comparable to the output of a star which for the Sun is three point eight times 10 to the 26 watts such civilization would be using stars as engines effectively harnessing them using constructions such as Dyson spheres perhaps finally a type three civilization would have a power consumption comparable to a galaxy that's something like five times ten to the 36 watts such a civilization would be so advanced it's very difficult for us to make any kind of predictions about what they would be like and thus there's probably not too much point worrying about type four or five or six beyond that either he might wind up where does humanity fall on this scale well it was Carl Sagan who extended cutter chefs idea to a continuous scale by noting that the energy levels are logarithmic Li uniformly distributed and this one can fit a straight line through the log of these three power levels so I'm showing you the three energy levels here let's repeat Sagan's calculation and fit the three power levels assuming a log linear law this gives us the following equation for our Kardashev level K where P is the power used by our civilization in watts now last year in 2007 humanity's average power consumption was 17.9 terawatts that would give us a Kardashev score of point six zero yeah you might say that point six isn't too far off one point zero but remember this scale is logarithmic so in order to go from point six to one we have to increase our power consumption by a factor of 1 million now there are those out there who would say no problem humanity's growth is itself exponential and this we should achieve type 1 status in a matter of centuries but if you get a calculator you can calculate when we will attain type 1 status the answer is in about a hundred years but does this check out okay so here's the average power consumption of humanity over time and at first glance you know such a claim seems reasonable it does look exponential if we take the logarithm of the power axis there then the growth certainly looks exponential even in log space up to the mid twentieth century and that's something we call hyper exponential growth but in more recent decades that hyper exponential growth behavior has shirt off and so clearly extrapolating this data into the far future is going to be sensitive to what model you assume okay so let me show you four models that I fitted to this data set first the most common is the exponential and a hyper exponential in red and orange respectively then a logistic and a hyper logistic model are coming in green and blue a logistic function looks like a leaning S and it mimics the growth of biological populations which tend to explode and then saturate at some maximum capacity level now as you can see all four of these models do a pretty good job of explaining the current data but if we go forward in time they give very different predictions about the future the exponential model sees us becoming a type one civilization by about 40 100 AD whereas the hyper exponential is far sooner in the mid 23 hundreds now whilst those numbers seem promising both of the logistic functions predict will actually stabilize our energy consumption way before becoming a type-1 predicting a maximum Kardashev score for Humanity of something like 0.65 now the real point here is to show you that you can come up with a wide variety of seemingly plausible models to explain the current energy trends we've seen in the last couple of centuries but extrapolating those models into the far future leads to wildly different predictions but for the sake of this video let's be optimistic let's assume that we do not saturate at some capped energy level but we keep on growing up to type 1 status so what would that even look like how would we increase our energy by a factor of a million today humanity gets his energy consumption from a variety of sources such as fossil fuels geothermal nuclear fission wind waves tides and solar first off fossil fuels are really not a contender as a pathway to becoming a type one civilization because even at current levels of usage we're likely to dry up our oil reserves in about a century let alone if we increased our energy demand by a factor of a million it's really not a Canada and that's not to say anything about the stupidity of turning your home planet into a giant greenhouse but what about using the earth itself let's take wind and wave power well the first thing to note there is the wave power is largely driven by the wind so you can't really double dip on both there is some debate about exactly how much energy is contained within the Earth's winds but we do know of course that winds are ultimately generated by the sun's energy warming of the atmosphere so a starting point is to note that the Earth's surface absorbs about 9 times 10 to the 16 watts of solar radiation now that power warms the entire earth but wind power is generated by the residuals the thermal differences between regions in 2004 Vaclav SMIL estimated that at best about two percent of this incident energy ultimately gets transferred to the air in of kinetic energy and so wind power has to be less than this number so put together wind power and by proxy wave power would have a maximum theoretical power level of about 1800 terawatts and that's assuming 100% efficient energy extraction now what about tidal energy though tidal energy is different it is generated not by solar radiation but by the gravitational influence of the moon and the Sun the total amount of power dissipated through tides by the Earth's oceans is now well determined with techniques such as old Timah tree satellite and lunar laser ranging all agreeing on a value of 3.7 terawatts and it's a similar story for geothermal energy which is ultimately driven by the internal heat of the earth itself that gives you about 47 terra watts again not at the right level for what we need now this just leaves us with two contenders left in the game solar energy and nuclear energy present-day nuclear power plants use fission to generate their energy that's the splitting of heavy atomic elements but it has long been a dream that we could exploit the nuclear fusion process in the future that's the combination of lighter atomic elements together now it's a long-running joke that nuclear fusion power plants are always 40 years away from us it never seems to get any closer but let's just make the assumption we'll figure this out one day and we will have nuclear fusion power a nuclear fusion can happen of the combination of really any two elements you want but the most energy efficient process identified for nuclear fusion power plants is the combination of deuterium and tritium now these two are heavy isotopes of hydrogen which is a fancy way of saying they just have extra and neutrons in their atomic nucleus than are hydrogen atom does now fortunately there's no shortage of deuterium here on the earth or something like 40 trillion tons of the stuff just in our oceans tritium however is far rarer it's only found in trace amounts inside water so typically it is produced by the reaction of free neutrons and lithium inside nuclear reactors that sounds great but lithium is also a fairly rare commodity - there's only about 30 million tons of the stuff in the ground in the reserves that we have but there's probably an extra 200 billion tons of the stuff dissolved in seawater so if we had access to all of that lithium that's dissolved we'll be able to make something like 90 billion tons of lithium now since each deuterium-tritium fusion reaction creates 17.5 9 mega electron volts of energy we would expect a total amount of energy that we could extract from nuclear fusion would be something like 5 times 10 to the 28 joules that would be enough to power type 1 civilizations energy needs for approximately 10,000 years so nuclear fusion could be a viable pathway to becoming a type one civilization but what about solar well of course solar energy is generated from the Sun and it's important to remember that the Sun is in essence a giant nuclear fusion power plant in the sky now on the earth one of the big problems with nuclear fusion is confinement how do you keep this hot plasma together at extreme enough pressures and temperatures in order to kick-start the nuclear fusion process but on the Sun confinement happens for free it happens from their own self gravity of the star itself yet more space is very empty and thus the transmission of energy from the Sun to the top of the Earth's atmosphere is essentially lossless finally there is clearly enough power to become a type one civilization from solar because that's actually how we define a type one civilization it's one which uses all of the solar radiation incident upon its planet so all you need to do is tie all your planet with solar cells and hate your a type one then I say wait where would I live well this doesn't mean there's no living space it just means all of the living space is underneath the solar panels however even this extreme scenario is probably not enough because solar cells are not 100% efficient modern solar technology is something like 25 percent efficient and there are some laboratory demonstrations which approach 50% efficiency but a one percent efficient solar cell is impossible and that's because the maximum theoretical efficiency of such a device is governed by the ratio of the temperature of the receiver to the temperature of the emitter in our case that's the earth to the Sun the so called Carnot efficiency of this system would be at best ninety five percent we could never do better than that and you might say no worries I'll just build a giant solar cell farm in space and beam the energy back to the earth but even that has some problems the conservation of energy now becomes your enemy energy cannot be destroyed or created it can only be transformed from one form to another and that's not some Jedi doctrine that's the first law of thermodynamics if a civilization uses a certain amount of energy to power their civilization that energy doesn't just disappear after they're done with it it becomes waste heat it warms their planet and that statement is true no matter what your energy source is be a solar nuclear or antimatter right now the waste heat generated by humanity's activities is so minuscule it really doesn't make any difference to the temperature of the planet but for a type one civilization it's a different kettle of fish one way to calculate this is to take the solar energy scenario and I'm gonna walk you through a very simple calculation for the equilibrium temperature of the earth that's a very basic calculation we often give our students an intro level classes here using the stefan-boltzmann law one can show that a planet's temperature approximately equals this where I've labeled here the various terms for you the albedo term is the key here that's how much light is reflected back into space without ever being absorbed by the planet for the earth it's about 30% now if you are a type one civilization you do not want 30% of this solar radiation to be reflected back into space that's energy that you need to power your civilization so by tiling your planet with very efficient solar panels you essentially make your planet very very dark dropping the hour bead over here down to zero so hopefully you can see from this equation that if I decrease the albedo I'm gonna raise the temperature and in fact it would raise the earth's temperature by about 24 degrees Celsius or 43 degrees Fahrenheit and that's really huge it would render large portions of your planet completely uninhabitable and you can't really Geoengineer your way out of this problem either for instance the idea of building a giant space space mirror such as in the trailer Clara hood that we did in the last video that's not gonna work because then you're reflecting away the very energy that you need to power your civilization and switching to a different energy source than solar say nuclear power is really not gonna help you in fact it's gonna make things even worse because now not only do you have to dissipate all of the waste heat generated by your nuclear reactors but you also still have to get rid of all of that energy which your planet is absorbing from the Sun anyway you have twice the problem to deal with so no matter how you look at it becoming a type one civilization is going to cause your planet to warm up so I would claim that a type one civilization maybe has two options for getting around this let me know if you have other options you can think of one would just be to build a giant air conditioner have everybody live inside and keep those small volumes cool okay another option which might be a bit more realistic I think would be that to relax this assumption that we have to live on a single planet to let our civilization spread out to the other planets and moons in your solar system that way you don't have to dissipate all of the energy in a single location allows you to keep each of those bodies a bit cooler so hopefully I've convinced you at the end of this video that becoming a Kardashev type one civilization would dramatically change our way of life it's not going to be business as usual now scientists like myself do these types of thought experiments and calculations because ultimately we're interested in what these realizations would look like in our telescopes and the only way you can really figure that out is to sort of put yourself in their shoes and imagine what your planet would be like which is kind of what we've done in this video if you're interested in the detection of such civilizations I'm actually helping to organize a meeting about that topic in Houston later this month so stay tuned on this channel for more videos after that meeting where I'll tell you about some of the techno signatures people were getting excited about hey if you've got this far through the video then you must have enjoyed the content so please consider subscribing to our Channel I bet this video will generate some pretty interesting comments and questions so please do put them down below and I will try to get back to you so until the next video staple [Music]

Channel: Cool Worlds

Views: 891,751

Rating: 4.8837357 out of 5

Keywords: Kardashev, Civilization, Advanced Civilization, Type 1, Type 2, Type 3, Type I, Type II, Type III, SETI, ETI, technosignature, dyson sphere, astronomy, astrophysics, planetary civilization, planetary city, nuclear, geothermal, solar, wind, waves, tidal, power, fossil fuels, david kipping, columbia university, cool worlds

Id: HEpNiOM6lto

Length: 16min 31sec (991 seconds)

Published: Tue Sep 11 2018

Reddit Comments

[u/firmakind]

That is a thorough, well put explanation that could be a fucking master thesis on its own. One day we'll have a dyson sphere, and all will be well. In the meantime, we need to focus on not turning the planet into a greenhouse while having the best energy output coefficient.

[u/Ascott1989]

Fusion is required. When Fusion reactors are created we will almost certainly become 1 ) A type 1 civilisation and 2 ) A multi planet species.