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Estimating SpaceX's Reusable Rocket Cost Savings (theverge.com)
An anonymous reader writes: On Monday, SpaceX successfully landed its Falcon 9 rocket after launching a group of satellites into orbit. It's a huge breakthrough for the commercial space industry, because reusing rockets will dramatically reduce launch costs. The question now is: by how much? Elon Musk says it takes $60 million to build the Falcon 9, and $200,000 to fuel it. That's a big difference, but we can't expect them to immediately launch the rocket again after refueling it.
"The Falcon 9 experiences major temperature changes during its flights, as well as intense pressures and vibrations from the winds in the atmosphere. These all produce wear-and-tear on the vehicle's hardware — meaning the rocket might need repairs and updates before it can launch again." This kind of refurbishing is why the Space Shuttle ended up being way more expensive than expected. Fortunately, the Falcon 9 is not nearly as complex.
This is now the true test of SpaceX's design talents; if the rocket is built to be durable, then repairs and replacements could keep relaunch costs very low indeed. Steve Poulus, a former NASA project manager, suspects final costs could be driven below a million dollars. That figure would give SpaceX the capability of easily underbidding any competitor for government contracts, not to mention bringing it into affordability for any number of companies who'd like to put a satellite in orbit.
"The Falcon 9 experiences major temperature changes during its flights, as well as intense pressures and vibrations from the winds in the atmosphere. These all produce wear-and-tear on the vehicle's hardware — meaning the rocket might need repairs and updates before it can launch again." This kind of refurbishing is why the Space Shuttle ended up being way more expensive than expected. Fortunately, the Falcon 9 is not nearly as complex.
This is now the true test of SpaceX's design talents; if the rocket is built to be durable, then repairs and replacements could keep relaunch costs very low indeed. Steve Poulus, a former NASA project manager, suspects final costs could be driven below a million dollars. That figure would give SpaceX the capability of easily underbidding any competitor for government contracts, not to mention bringing it into affordability for any number of companies who'd like to put a satellite in orbit.
1) The first stage is 2/3 the total cost to launch. Which would be $40 million.
2) They can renovate the first stage for $5 million.
3) They can get five launches from a first stage (original plus four more).
So, $60 million for five launches, plus the $20 million for the second stage x5.
Which comes to $32 million per launch. A bit more than half the current price.
Now, I consider those pessimistic assumptions.
Alternately...
If we replace (3) with 15 launches per first stage, we get $28M per.
If we replace (2) with $1M per launch, we get $29M for five launches, $23.75 per launch for 15 launches.
Big picture: reusing the first stage only will allow them to drop prices by 40-60%.
Now, if they can reuse the second stage also, we're talking some real money....
"I do not agree with what you say, but I will defend to the death your right to say it"
Elon Musk and company have been making huge achievements and seems one of the few people in industry to take the long view of things and it's likely to pay off in the end even though the MBAs hate him at the moment.
I, for one, welcome our new Martian overloard!
"Be particularly skeptical when presented with evidence confirming what you already believe." -
1) The first stage is 2/3 the total cost to launch. Which would be $40 million.
2) They can renovate the first stage for $5 million.
3) They can get five launches from a first stage (original plus four more).
So, $60 million for five launches, plus the $20 million for the second stage x5.
Which comes to $32 million per launch. A bit more than half the current price.
Now, I consider those pessimistic assumptions.
Interesting numbers. Let's try a variant case. Suppose in addition:
You're assuming that the non-reusable launch vehicle cost per launch is $60M. OK, let's start out by assuming 1/3 of that is fixed costs and operations costs, and 2/3 the vehicle cost, which is split evenly between the two stages (first stage is larger, but not proportionately more expensive). So, of the $60 million, $40 million is spent even if the vehicle first stage was free.
Now assume that re-usability increases the launch cost by, say, $5 million (launch operations are expensive! and the cost is not entirely the vehicle).
Assume that all the stuff needed to make the first stage reusable increases the stage cost by 25%, from $20M to $25M.
And assume that the delta-V and the added mass to do the fly-back decreases payload by 10%, and that the price you sell the launch for decreases a similar percentage (some payloads won't care, but some will.)
economics are much less clear now. The first stage cost drops with refurbishment from $20M to $6M, but the total launch cost only drops from $60M to $51M, whereas the price you can sell the launch for drops from $60M to $54M.
Still an economic advantage... but only a few percent advantage.