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Holy cow! I just read the energy requirements of that third mission. Total electricity generation capacity of the entire world is about 12TW today [1], whereas that 3rd mission would require a "formidable" - as the author admits - 45,000TW at least. A mere three orders of magnitude more :)

[1] https://www.statista.com/statistics/267358/world-installed-p...



I have a confused question here. I asked chatGPT what the approx terawatt output of the sun is. It claims it is 384.6 terawatts. I find that hard to reconcile with the earth having 12TW production. Given that your number is probably OK, that would suggest the sun output calc is way off. I wonder if any non-AI contributors have better ballpark estimates for the sun's energy output.. Hmm, I found a non-chatGPT source, which claims the same.. https://www.rmg.co.uk/file/2277/download?token=KyEQPN9O

If this relation is really true, I am somewhat shocked - us burning 1/30th of the suns energy output, can that really be true..?? If so, scary. And also 'illuminating' concerning how unsustainable what we are doing is..?

I do hope my numbers are off.


I'm really not trying to sound condescending here, but your maths is WAY off. Where did you get 384.6 TW from? Your actual source says

   The power output or luminosity of the Sun is 3.8 x 10^26 W
For reference that's 3.8 x 10^14 TW - so your little AI friend is a cool 12 orders of magnitude off here.

Bottom line: do NOT rely on figures provided by generative models. The chance of them being completely wrong seems to be alarmingly high.


thank you, you are indeed right. To wit (for people like me) - 3.8 x 10^26 W 3.8 x 10^23 kW 3.8 x 10^20 MW 3.8 x 10^17 GW 3.8 x 10^14 TW


This says we use about 1/10000 of the solar energy that hits the Earth at any given moment.

https://phys.org/news/2011-10-vast-amounts-solar-energy-eart...


That's a very nice figure for context. So the energy required would be about 26% of that. That means it's more power than we could ever hope to capture from solar alone, as only about 29% of the surface is land and some of that isn't particularly great for solar (looking at you rain forests and Antarctica:)

Unless we use space-based systems instead, which would make that a kind of power requirement trivial, ignoring the costs of course ;)


I'm not following the math.

Taking the US as an example: depending on who you ask, we could generate enough power for the US with somewhere between 10000 square miles (Elon math) and 21250 square miles (pretty common number given by multiple other sources) of PV.

That is about a fifth of the state of Nevada. A lot of PV, to be sure, but far from beyond hope.

And that assumes nothing but PV, which is unrealistic. We capture a bunch of the sun's energy as wind and rain.


Sorry for the confusion - I was referring to the energy requirements of the interstellar mission, not the power generation of the world.




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