Value chain · CLM-1453
In plain terms
A 2021 UK study estimated what it would cost to carry satellites to high orbit on two reusable launchers: 3,260 dollars a kilogram for SpaceX Starship and 1,340 pounds a kilogram for the British SABRE spaceplane. The study does not set the two side by side in one currency, but converted at any of the exchange rates it lists, the Starship figure is the higher. The cost range its model actually uses runs from 358 to 2,410 pounds a kilogram.
The claim as recorded
The UK study's input-data annex gives two launch-cost points to GEO, in its own words: SpaceX Starship at "$3,260/kg", from 61.3 tonnes on two launches at a cost per launch comparable with the "current cost for SpaceX Falcon Heavy, $100M"; and a Reaction Engines SABRE spaceplane at GBP1,340/kg, including chemical tug refuelling flights, at four flights per vehicle per week and GBP7.5M per flight. The paragraph prints the two in different currencies, but the same annex states that "All cost data are converted into Pounds using an exchange rate from their year of origin" and lists GBP/USD rates for 1990 to 2021, from 1.2769 (2019) to 2.0016 (2007), with 1.3642 for 2021. By our arithmetic on those rates, the Starship figure is about GBP2,390/kg at the 2021 rate and is the higher of the two at every listed rate, since the two are equal only at USD2.43 to the pound. The model's own input is a log-uniform Spacelift Cost per Unit Mass of GBP358 to GBP2,410/kg.
Scope and limits
Both figures are the study's estimates for future high-flight-rate operations, not prices paid. The source itself does not rank the two; the conversion and the ranking are ours, on the source's rates. The page does not say how either bound of the model range was set: 3,260 at the 2021 rate gives about 2,390, not 2,410, and nothing on the page gives 358 (our arithmetic). The same page quotes a Reaction Engines prediction that cost falls "from $400/kg to $100/kg" as the flight rate rises from 1,000 to 10,000 a year; this record does not use it.
What it assumes
The source does not say which year's rate applies to either p.11 figure. The 2021 rate is used for the single converted figure because the Starship price rests on the "current" Falcon Heavy cost in a 2021 document; the ranking holds at every rate in Table B3, so it does not depend on that choice.
Where it comes from
PDF p.11 (index 10), in document order: Starship first - "an estimated 61.3 tonnes can be delivered to GEO with 2 launches. Assuming a cost per launch comparable with the current cost for SpaceX Falcon Heavy, $100M, the cost is $3,260/kg" - then SABRE - "Reaction Engines has developed estimates for the production and operation of a spaceplane. Assuming a flight rate per vehicle of 4 per week, an operating cost of GBP7.5M per flight... the total cost to GEO, including the cost of chemical tug refuelling flights, is GBP1,340 / kg". Model input at PDF p.5 (index 4): "Spacelift Cost per Unit Mass (GBP/kg) Log-uniform 358 2410". PDF p.3 (index 2): "All cost data are converted into Pounds using an exchange rate from their year of origin" and then expressed in 2018 values with GDP deflators, at the rates in Table B3 (paraphrase). PDF p.12 (index 11), Table B3, GDP deflators and GBP/USD conversion rates by year: 1.3642 for 2021, 2.0016 for 2007 (the highest) and 1.2769 for 2019 (the lowest). Our arithmetic: 3,260 / 1.3642 = 2,390; 3,260 / 2.0016 = 1,629; 3,260 / 1,340 = 2.43.
Basis: USD and GBP as printed on PDF p.11; the annex states that it converts cost data to pounds at the exchange rate of their year of origin and expresses them in 2018 values (PDF p.3); the conversions of the Starship figure here use the annex's own GBP/USD rates and are our arithmetic
Related records
- Answers question
- QST-003 not published in this release
- Supersedes
- CLM-0716 not published in this release
Cite this
energyaperture.com/c/clm-1453
CLM-1453, Energy Aperture, as of 2021.
Connected records
Other published records linked to this one. A list, not a judgement.
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