SRC-532

Satellite Power Systems (SPS) Space Transportation Cost Analysis and Evaluation; DOE/ER-0086; November 1980

Commissioned by U.S. Department of Energy, Office of Energy Research, Satellite Power System Project Division; Under Contract No. 31-109-38-5397. Who paid for a study is recorded because it bears on how its conclusions should be read, not because it makes them wrong.

Published claims resting on this source

• CLM-1024 The 1979 government estimate put a heavy-lift flight at about ten million dollars of the day, most of it people refurbishing the vehicle, which works out at about thirty 1979 dollars for every kilogram put into low orbit. That is the number the programme's later cost goal was built on.
• CLM-1026 The electric ferry takes half a year to climb to geostationary orbit but burns about an eighth of a kilogram of argon for every kilogram it carries; a chemical stage would burn two kilograms of propellant per kilogram and need almost three hundred trips per satellite. That ratio, not speed, is why the programme chose electric.
• CLM-1027 Getting a crew from low orbit up to the construction site took half a day and a stage the size of a small airliner, refuelled at the top with fuel the slow electric ferry had carried up. Counted fully, moving one worker's year of labour into orbit cost about a million 1977 dollars.
• CLM-1028 Building the rockets was priced at seventeen billion 1977 dollars and running them at about 2.8 billion per satellite, or roughly sixty 1979 dollars for every kilogram of satellite delivered to its final orbit. Most of that was the launcher; the electric ferry was a fifth.
• CLM-1029 In 1980 the programme's own accounting had rockets at roughly one dollar in four of a satellite's cost and nearly one in two of the money needed to develop the system, and it noted that the whole programme through the first satellite cost about what NASA had spent from its founding through Apollo.
• CLM-1030 The independent 1980 cost review said the government's rocket numbers were fair for the stage the programme was at, then added spare vehicles because the plan assumed nothing would ever fail, roughly doubled the risk on the electric ferry because its unit price assumed a factory that did not exist, struck out the dedicated crew launcher, and put the running cost about eleven per cent higher with a much wider error band.
• CLM-1031 A launcher a third the size of the reference one would cost about a fifth more per kilogram to fly and need four launches a day instead of one, but would save five billion dollars up front and add only three per cent to the cost of each satellite. By 1981 everyone involved wanted it.
• CLM-1033 At the higher of NASA's two peak figures, the launches would have needed about 6 per cent of US daily hydrogen output and 30 per cent of its oxygen, and making the hydrogen by splitting water would have consumed about half the output of one of the satellites being launched. NASA's own report gives two different figures for how much fuel that is.
• CLM-1034 The programme's transportation workshop said the schedule was probably unrealistic, and the programme's cost reviewer said the launcher fleet was too small for it: about one launch a day on a five-and-a-half-day turnaround with no reserve vehicles, and a fleet of slow electric ferries with no slack for accidents.

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