Comment Re:It's almost hard to imagine what it really mean (Score 1) 104
You have been able to reach anywhere on Earth since decades ago, and without the need for the 1000 tons of methane and 3000 tons of oxygen that Starship consumes to get up.
Where to even start with this?
1) Liquid oxygen is dirt cheap. Generally numbers of $0,10-$0,20/kg are cited for large volumes (the DoD pays $0,27/kg, but well, that's the DoD, and current volumes aren't that great). The energy cost at current US electricity prices is $0,08/kg.
2) Methane is a cheaper, more abundant, easier to manufacture, lower-carbon fuel than oil per unit energy. All fuels are not interchangeable. LNG costs $0,45/kg (a bit more for LM) and aviation fuel at $2,40/kg . 1/5th the cost. Adding in LOX at $0,14/kg at a 3,6:1 ratio to $0,50/kg LM, we get a total of about $1/kg methane total cost.
3) Earth-to-Earth for sub-10k km distance is single stage. Only the upper stage is used. It only consumes 1/4th the methane of a full launch stack. 1200t total propellant, which with a 3,6:1 LOX:fuel ratio, equals 260t methane.
The big question is the number of passengers. Starship's payload volume is friggin' huge, and there's no need for first class or even bathrooms because a flight is so short. An A330 carries a max of 170 tonnes (though it won't use *all* of that even on a long transpacific flight) and carries a couple hundred passengers, depending on the config. So from a propellant cost perspective, burning ~130t on a transpacific flight might be the cost equivalent of 310t of methane + its oxidizer, or 1400t of total methalox.
OH HEY, whatdjaknow...
Yes, rockets burn a lot of fuel, VERY quickly. What they don't do is then continue to burn fuel for hour after hour pushing against the atmosphere.
Of course, it's not just about propellant cost - it's also about operations costs. While propellant is much easier to compare, operations cost isn't at this point. What we can say is that the minimum theoretical turnaround on Starship is 1-2 orders of magnitude less than on a transpacific flight. Probably 1 order of magnitude minimum (or less) in practice after accounting for passenger and prop loading. But all issues of ultimate unit cost, maintenance, ground systems costs, etc per flight are yet to be clear.
Will this "let us settle unsettled areas"? Of course not. But there is very much a potential economic case, IF it matures right.
(The main "industry" I see salivating over these super-short high-payload delivery times is, of course, the DoD. Armoured vehicles, anywhere within 10k km, in an hour? "SHUT UP AND TAKE MY MONEY!"