What might a Kardachev 1 Look Like?

[speaker-to-trolls]

For those who haven't heard of it the Kardachev scale is a meadure of the amount of energy a civilisation uses which rises exponentially, so level 0 I'd guess is hunter-gatherer level, level 1 is all the energy of one planet, level 2 is all the energy of one star and level 3 is all the energy of one galaxy (and level 4 is not particularly well defined but would presumably be a lot bigger than level 3). Level 2 civilisations come up a lot in science fiction and speculations about advanced aliens or future human civilisation, I'm wondering if anyone has a good idea what a level 1 civilisation would be capable of, and what one could do to harness the energy of an entire planet?

I would guess that energy generation would come mainly from nuclear power and huge solar panel farms, either covering uninhabited areas or out in orbit. I also wondered if it might be possible to harness things like techtonic plate movements or the energy in the Earths rotation for power. If not (and it sounds pretty silly, I know) then a Kardachev 1 would at least be able to drill down into the mantle to take better advantage of geothermal energy.
I'd also suppose they would have a certain capacity for practical space travel in their own solar system, but I'm not sure how far that would extend (depends on how interested the civilisation in question is in it, clearly). I mean if Earth was a type 1 civilisation could we expect large scale colonies on the moon? Mars? the moons of the gas giants?

PS: I used to preface these things with "I'm writing a story about x" but I haven't written anything creative in... probably over a year now. I'm just curious about this.

[Solauren]

Coruscant byitself would be a Kardachev 1. Just add on food production facilities.
Cybertron would also be another one. So would Unicron for that matter.

[Darth Ruinus]

Coruscant byitself would be a Kardachev 1. Just add on food production facilities.
Cybertron would also be another one. So would Unicron for that matter.

According to this wouldn't a Star Destroyer's reactor output be comparable to a type I?

[Sky Captain]

I can`t imagine how K1 could exist as purely earthbound society. All that generated energy would eventually turn into heat. If we were generating 10^16 W on Earth it could cause Earth to overheat. Most of that power would probably come from solar power satellites, fission and fusion reactors adding significant amount of heat to Earth natural energy balance.

However for civilization with well developed space colonization it would be easy to reach and surpass 10^16 W figure since most of that energy would be generated and dissipated in space. Even single large interplanetary Orion spacecraft could have engine power output approaching K1 number.

[Surlethe]

I can`t imagine how K1 could exist as purely earthbound society. All that generated energy would eventually turn into heat. If we were generating 10^16 W on Earth it could cause Earth to overheat. Most of that power would probably come from solar power satellites, fission and fusion reactors adding significant amount of heat to Earth natural energy balance.

Would you mind running numbers on that? The amount of solar power falling on the Earth is about 1.7e17 W; what would making it 1.8e17 W do to the planet?

[Illuminatus Primus]

According to this wouldn't a Star Destroyer's reactor output be comparable to a type I?

No, that's actually closer to the type II's [!] power.

Coruscant seems close to the scale and lifestyle I'd expect. Its population is huge, up in the single digit trillions, and the people seem to live an energy full life with their flying cars and droids that we see in the films. If you count its own food production, manufacturing, and other industry, it should fit the description.

Of course when comparing power output to Star Destroyers one must remember we're looking at instantaneous peak output (the Star Destroyer spends the vast majority of its time idling by comparison), where as the K scale is based on time-average continuous output.

[Steel]

I can`t imagine how K1 could exist as purely earthbound society. All that generated energy would eventually turn into heat. If we were generating 10^16 W on Earth it could cause Earth to overheat. Most of that power would probably come from solar power satellites, fission and fusion reactors adding significant amount of heat to Earth natural energy balance.

Would you mind running numbers on that? The amount of solar power falling on the Earth is about 1.7e17 W; what would making it 1.8e17 W do to the planet?

Black body radiation goes with T^4, so increasing the power output by 10% is going to raise the temperature by a factor of 1.1^0.25 = 1.02, so about 6K on average. Not a massive increase for a long term change, but could be quite damaging to existing ecology if you suddenly dumped that on the planet.

[Sky Captain]

I can`t imagine how K1 could exist as purely earthbound society. All that generated energy would eventually turn into heat. If we were generating 10^16 W on Earth it could cause Earth to overheat. Most of that power would probably come from solar power satellites, fission and fusion reactors adding significant amount of heat to Earth natural energy balance.

Would you mind running numbers on that? The amount of solar power falling on the Earth is about 1.7e17 W; what would making it 1.8e17 W do to the planet?

Black body radiation goes with T^4, so increasing the power output by 10% is going to raise the temperature by a factor of 1.1^0.25 = 1.02, so about 6K on average. Not a massive increase for a long term change, but could be quite damaging to existing ecology if you suddenly dumped that on the planet.

It seems I buggered up my statement a bit. I originally thought about basically doubling amount of energy naturally falling on Earth and consequences of that. 10 % of power increase may be survivable although polar ice caps would go and massive changes in weather patterns are likely, some forms of positive feedback mechanisms also may kick in like large scale methane release from thawing permafrost resulting in increased greenhouse affect.

Anyway true K1 civilization would most likely spend largest part of it`s power usage in space transportation and mining operations since it seems highly unlikely to have trillions of people living on Earth without large scale space colonization and industrialization projects and massive usage of from space imported materials.

I also can imagine large increase on civilization`s overall power usage when technology progresses to the point where middle class individuals can afford their own spacecraft.

[speaker-to-trolls]

However for civilization with well developed space colonization it would be easy to reach and surpass 10^16 W figure since most of that energy would be generated and dissipated in space. Even single large interplanetary Orion spacecraft could have engine power output approaching K1 number.

As Illuminatus Prime commented on the stardestroyer figure, though, that energy would be released instantaneously in little bursts, not maintained as a continuous average. Oddly, if I understand these figures correctly, a Type 1 civilisation could probably have hundreds or thousands of these spacecraft.

I'm a bit confused by teh speculative population figures here; they're basically derived from a K1 civilisation having about 20,000 times the energy output of modern America, so you could have trillions of people living like modern Americans. Wouldn't the actual figure be lower than that, since they would also be using more energy per head than modern day people? So say instead of a trillion people living like modern day upper-middle class Americans we have two hundred billion living like rich Americans.

[Sky Captain]

However for civilization with well developed space colonization it would be easy to reach and surpass 10^16 W figure since most of that energy would be generated and dissipated in space. Even single large interplanetary Orion spacecraft could have engine power output approaching K1 number.

As Illuminatus Prime commented on the stardestroyer figure, though, that energy would be released instantaneously in little bursts, not maintained as a continuous average. Oddly, if I understand these figures correctly, a Type 1 civilisation could probably have hundreds or thousands of these spacecraft.

I'm a bit confused by teh speculative population figures here; they're basically derived from a K1 civilisation having about 20,000 times the energy output of modern America, so you could have trillions of people living like modern Americans. Wouldn't the actual figure be lower than that, since they would also be using more energy per head than modern day people? So say instead of a trillion people living like modern day upper-middle class Americans we have two hundred billion living like rich Americans.

That is most likely that per capita power usage for K1 civilization is going to be higher than Americans have today although I don`t know how much higher. If dozens of millions of people can afford and regularly fly their own spaceplane then average power usage is going to be many times higher than it`s today. I can imagine K1 civilization having something around 100 billion citizens although real figure probably depends how developed space colonization and industrialization is since spaceflight is the most energy intensive thing. Even civilization with few dozen billions of people can be K1 if they all live like rich people today and interplanetary travel has reached the point when going to Mars is like today going from Europe to America and tourist cruises through solar system are common thing.

[Ender]

Of course when comparing power output to Star Destroyers one must remember we're looking at instantaneous peak output (the Star Destroyer spends the vast majority of its time idling by comparison), where as the K scale is based on time-average continuous output.

Yeah, time averaged looks to be about a terawatt, so we are talking a consumption level of about the United States. Of course, there are 1/10000 th as many people on the star destroyer, so...


Destructionator, I'm curious as to the ratios you used for evaluating how many people you can fit and how you then extrapolated that to the number of ships. Most stuff I've seen like Mining the Sky puts forth a far greater population number. And I'm not following the relationship between number of people to number of states to number of ships. Could you expand upon this please?

[Ender]

First, we want to determine how much mass would need to be produced per person:

Adequate radiation protection, outside of solar flare events, can be provided by approximately ten tons of imported lunar regolith per square meter of hull surface [Johnson 1975]. Radiation shielding thus dominates the mass of the system.

Ten tons / square meter. How many square meters?

http://spaceset.org/p.train6.mm (See table 1 about half way down the page, and note it cites NASA studies again. I read through many of those studies when I made my rules of thumb in the first place, but forgot where to find the references quickly.)

About 155 m^2 / person is the total, but I'm only going to look at the residential stuff, since it is what should scale most linearly with population (everything else is commons). That number is about 50 m^2/person, which works out to about 500 tons of material mined, on average, per person. Much of it is slag or plain unusable for building ships. I had an estimated number for this, but can't find it now; anyway, 10% being usable seems conservative and gives an easy number to work with. Thus, 50 tons of useful material per person is produced in this economy.

If we assume that about 1% of the useful material mined can be used for military purposes, that gives you about half a ton per person. Assume that your average space warship + its support infrastructure works out to about 100,000 tons a piece (this number being primarily from various designs I've made for my own hard sf setting combined with some guesstimation from the size of ships in the US Navy), and you get about one warship for every 200,000 people.

Population numbers can be determined in one of two ways: either try and project population growth for X years into the future, which requires a target year and an average growth rate, the latter being virtually guaranteed to be inaccurate (but can be mitigated with some rigor and justified with a setting's backstory), or take this mass number per person and see how many people you can get using up a chunk of the solar system, simply assuming we are in the far future and had positive growth the whole time.

Now, just using the mass alone is going to be inaccurate too - the limiting number, even with material, is probably going to be something the body needs but may be rare in space (phosphorus is an element I've seen thrown around as a problem in the studies), whereas the bulk of this mass production is probably going to be used for building habitats, and thus will be dominated by elements like iron and aluminum.

Nevertheless, on the large scale, when using up everything, assuming a proportional distribution of the bottlenecks seems like a somewhat safe assumption; with large numbers from a wide, assorted pool, these things tend to balance out. We should at least get an order of magnitude estimate.

Wikipedia says the total mass of the asteroid belt is about 3.0x10^21 kilograms. [ wiki link ; note they cite a real source, but I haven't bothered to read it myself ] This is 3e18 tonnes.

Let's go ahead an include the common areas for total use, fetching the number from the same link and using the same method as above. This works out to about 1550 tons per person. So if we mined the entire asteroid belt and turned it into space colonies, we would be able to support about 3e18 / 1.55e3 = ~2e15 people, which is nearly two quadrillion.

The number is huge. Note the mass per person is probably an underestimate; it was based on livable surface area * mass needed for radiation protection of this surface area. The real number would be bigger, as people would want to use material for building their houses inside the habitat, for the production of personal vehicles, and much more. It also neglects the atmosphere and soil inside the habitat, and water, etc., etc. (justified since the study said the radiation is the bulk, but nevertheless, it still contributes to making it an underestimate).

Of course, most the mass from people eating and other day to day activities would be recycled, like it is on Earth. So we only need to count that once, rolling it into the overall mass per person calculation without worrying about number of years our civilization has been around.

Taking all that into account would bring the population down quite a ways. Anything in the trillions is probably justified by this analysis, with the numbers leaning up toward the hundreds of trillions.

And this would mark the difference I expected. Most sources I read posited a population cap of somewhere between 10^16 people and 10^18 depending on hor far in to the system they limited themselves.

However they use a different limiting factor. Instead of shielding material, they used water. The reason being here, water could be used a shielding material. Build spherical colonies and you can rapidly inflate the total population as the amount of water consumed is far less then the amount needed for shielding.

BOTE time
I'm going to use your numbers here, assuming that that regolith is of predominantly iron composition since I can't find the TVT for silicon dioxide. We would be talking about apiece of shielding ~1.27 meters thick. A comparable water shield would need to be 7.62 meters thick and mass 7.62 tons per m^2 (TvT of iron ~4 inches, Tvt of water 24 inches). Now a person uses about 500 liters of water a day, so thats 500 kgs. So every meter of shielding can support 15 people. Now I'm going to make a leap here determining the volume a person needs by going with the size of a a studio apartment. A quick google search says 300 sqft is reasonable. This is about 84 m^3 when you factor in the usual 3 meters to a story rule of thumb. Lets round it up and say each person gets 100 m^3 of space.

So now 15*(4*pi*r^2)= P and ((4/3)*pi*r^3)/100 = P where r is radius and P is number of people. Setting these equal to each other, we get a radius of 4500 meters to give us the size of our optimal habitat. This will hold 3.82 billion people. Lets call this an even 3 billion for simplicity and to allow for a lot of common space. After all, we can expect that as time goes on luxury and space will increase. This habitat requires 1.85 billion tons of water for shielding.

So how much water and ice is there in the solar system? "A lot" is an understatement. If the interprations I've read ofthis paper are correct, then saturn's rings alone are 3x the mass of Mimas, or ~10^20 kgs. Plus there is a lot of water in the gas giants, asteroid belts, planets, and of course all out comets. Obviously water will be in high demand for a number of things such as propellant for spaceships. But even if we limit ourselves to only using Saturn's rings for human consumption and using the rest for industrial applications you are talking about over fifty million of the above habitats for ~10^17 people

Obviously this is very BOTE - no doubt my shielding numbers should go up based on the material. Plus while habitats that size would be the optimal, more likely there will be numerous smaller ones instead. Still, I think using water as the determinant is a better stance to take, so if you are going to redo your stuff in the future I would recommend using that.

My usage of single digit trillions in the post linked above was biased due to my own setting, which takes place within the next 2,000 years and had modest growth, and thus hasn't used up the entire asteroid belt yet; I thought the 10x multiplier would take care of that, but looks too small! (I've since revised the setting, so this also is no longer true, but that's not important right now.)

Honestly, I didn't realize my bias there until just now. I make so many assumptions for my own setting and while I try to point them out in my posts, sometimes a few slip into my general thinking without me consciously noticing it. This is one of those times. Always read stuff anyone says with a critical mind!


So, anyway, near Earth materials give you a lot of people. Asteroid belt gives you into the hundreds of trillions. Kuiper belt is as high as into the double digit quadrillions more (using a mass number form wikipedia again "It is similar to the asteroid belt, although it is far larger -- 20 times as wide and 20–200 times as massive" link).

God, the solar system is so fucking huge!

Yep. Only problem with the Kuiper belt being a resource supply is that by the time you need it, your population has grown to the point where reproduction rates and travel times means that you won't be able to import fast enough. I went out to Saturn for my comparison, but really I think we will be limited to what we can grab in the inner system because otherwise the distances are just too great.

And I'm not following the relationship between number of people to number of states to number of ships. Could you expand upon this please?

This was just an average: the US Navy has about 300 ships (Navy.mil), and the US has of course 50 states. 300/50 is 6 ships per state, on average. Under my old, old, obsolete method of determining sci fi fleet sizes, I would call one member planet a state, and give each state about these 6 ships. So a 150 member planet Federation gets 900 assorted ships in its starfleet.

(See, back in the day, my setting had heavy Star Trek influences, and this simple method gave me numbers that seemed reasonable for Star Trek, so I ran with it. I don't mind it for planet based space opera, but it seems much too small for any kind of hard sf setting, even if you call each space habitat a state - the mass analysis leads to as many as 100 warships for an O'Neill cylinder pair, far greater than the 6-12 this average would suggest. Of course, both may work out, depending on your own setting; maybe your countries have a bigger or smaller military budget than the 1% I'm using here, or different sized/more maintenance heavy ships, and so on.)

Come to think of it, spacecraft would dispose of mass with every year of their use. While people can recycle material, spacecraft would throw some out the back as propellant, thus increasing their cost. This may be significant and might lower the number seen. My one ship / 200,000 people rule of thumb neglects this entirely! So my ship numbers should probably be seen as an upper estimate (certainly not an upper limit though; military budgets could be higher than I'm assuming).


Though, back to the US, 300 ships / 300,000,000 people is about one ship per a million people, which isn't too far away from the one ship / 200,000 people my guess based on masses comes up with, making me think my method does indeed give a decent order of magnitude estimate.

Well taking these rules and extrapolating to the above numbers I derived we are talking about 10^8 ships if based of number of habitats and 10^11 ships if based of total population. But asyou said they need revision.