
How many calories does it take to bring a calorie to the ISS? - ColinWright
http://blogs.esa.int/atv/2013/01/25/
======
gus_massa
It's very interesting, but it's only the strictly minimal amount. It doesn't
include the additional weight of the rocket and fuel.

Let's estimate that. [From: <http://en.wikipedia.org/wiki/Ariane_5> ]

The total launch mass is ~800T and the payload to ES is ~20. All the energy
calculations are linear in the mass, so we have a x40 factor.

But obviously not all the rocket and fuel reach the ISS, so not all the
initial mass should be lifted and accelerated. We have to make some kind of
differential equation that depends on a lot of details that I don't know. But
from similar calculations I guess that a x1/3 factor is not very far from the
correct number. Let's be optimistic and pick x1/4.

So, if the minimal is 1.6 c.b., then my uninformed guess is that the total
amount is 1.6x40x1/4 =~ 15 c.b..

I'd really like to see a estimation made from someone with more knowledge, or
one based in the energy contained in the fuel.

