5
$\begingroup$

I want to have a worldwide superstructure, covering all usable land and all usable continental shelf. Assuming that the Burj Khalifa is about as high as we can go, how many people can I have in my world-wide superstructure?

The tallest man-made structure in the world is currently (2016) the Burj Khalifa at about 830 meters tall, with 154 usable floors, and about 300,000 sq. meters (3.2 million sq. ft) of usable floorspace. However, the Burj tapers off towards the top, so a mega-structure might have more space. Think of this as a "floor" estimate, hah!

coruscant
For some reason we painted it pink.

Moreover, I want to spoil all the residents, so with the gardens, vast open atriums, pools and all that, each resident will take up 10,000 sq. meters (107,000 sq ft) of space.

cutesy atrium image
View from my bedroom

Keep in mind that the Burj actually has much more space, it's just dedicated to maintenance, structural support, quake-proofing, etc.

Edit: Assume that food is not an issue: these urbanites are either kelp-farming the ocean, keeping the farms underground near the fusion reactors and anti-quake stabilizers, or growing it in orbital farms linked by space elevators, whatever.

$\endgroup$
  • $\begingroup$ Food may not be an issue; what about heat pollution from all of those fusion reactors? It's likely to be quite significant. $\endgroup$ – Mike Scott Feb 5 '16 at 16:41
  • $\begingroup$ @MikeScott, if we need the occasional vent-to-space and/or use bottom of the ocean for cooling and/or cover some part in radiators, that's fine, too. $\endgroup$ – Serban Tanasa Feb 5 '16 at 16:48
  • $\begingroup$ As much as I love your questions, including this one, this question is, unfortunately, an Idea Generation question. I'm hating myself a bit, but I'm voting to close. $\endgroup$ – T. Sar Feb 5 '16 at 17:05
  • $\begingroup$ @ThalesPereira - Are you sure you have the right question? I am asking for a number or range, specifically max population given some constraints. How is that idea generation? $\endgroup$ – Serban Tanasa Feb 5 '16 at 17:06
  • $\begingroup$ Now I'm starting to get your question. "What would be the population" was to me something like "how this people would be", and not "how many people could live there". This is a bit of a language barrier, I assume. On my native tongue, the direct translation of that would be more likely my interpreation. $\endgroup$ – T. Sar Feb 5 '16 at 17:08
3
$\begingroup$

185.05 billion individuals.

There are 148,940,000 km2 of land on Earth and approximately 36,113,200 km2 of continental shelf totalling 185,053,200 km2. You didn't give a floor height for your residents, but if they got the whole 830 meters in their 10,000 m2 of space then you can fit 18.505 billion individuals. More reasonably, you can provide everyone with 83 meters of vertical space, this allows ten plots to be stacked vertically. Thus, you have space for 185.05 billion individuals.

Of course, you'll more likely have families or couples living together in a space (unless they just get adjoining spaces) so your population could be two to four times larger for couples and small families.

$\endgroup$
  • $\begingroup$ If you use a more normal floor height of 3m, you get about 5 trillion people. $\endgroup$ – Robin Bennett yesterday
2
$\begingroup$

Regardless of the size of the buildings, there has to be some basis on who actually lives in that space. In the Burj, no one lives in the tower, just the Y shaped base. If you're covering the planet with megastructures, and looking for the maximum number of people, you would use something similar to existing megastructures. The most populous metropolitan area in the world currently is Tokyo, Japan, with 37,833,000 people in an area of 5,200 square miles. This is approximately 7275.5769 people per square mile, which is a lot... unless you've got approximately 154 usable, habitable floors on the thing, which is a cozy 47 people per floor, per square mile.

If you're going Coruscant-level construction, covering the entirety of landmass on Earth today (57,308,738 square miles), that will give you 4.169541303609522 × 10^11 people... about 417 billion Average Joes.

$\endgroup$
1
$\begingroup$

The base of the Burj Khalifa covers an area of roughly 3.5 acres.

There are roughly 7 billion acres of usable land on earth by the given requirements, which means you could cover the earth with approximately 2 billion Burj Khalifas.

The Burj Khalifa has 300,000 square meters of space, so if each person has 10,000 square meters of space you could fit 30 people in the space of a single Burj Khalifa.

That establishes a maximum population of roughly 60 billion people in an earth whose surface is entirely covered in Burj Khalifas.

I will note that 10,000 square meters of space is a lot of space, and the infrastructure of the Burj Khalifa that doesn't figure into the 300,000 square meter calculation could easily (with the benefits of economies of scale) house the infrastructure to support this population.

Especially when you consider how advanced a civilization that could build this megastructure would be.

I was going with arable land...the total land area of earth is roughly 40 billion acres, so (40 / 7) * 60 billion = ~340 billion people.

A trillion if you assume the structure is uniform with no gaps or taper.

$\endgroup$
  • $\begingroup$ I'm not sure where the 7 billion acres estimate came from, can you expand on that? (cite?) The surface area of the land plus continental shelf is surely greater, and moreover the Burj tapers off, while a megastructure could be untapered... $\endgroup$ – Serban Tanasa Feb 5 '16 at 17:20
  • $\begingroup$ My mistake, I was using arable land, not total land. Total land is roughly billion acres (total area of earth is 125 billion acres, 2/3 water). So about 340 billion people total. Also, it's an order of magnitude estimation, so double or triple it to account for the taper. Say a trillion people to be fair. $\endgroup$ – zagdrob Feb 5 '16 at 17:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.