Value chain · CLM-0212
In plain terms
In the 1978 design, the equipment that moves and controls electrical power on board makes up about one fifth of the satellite's total dry weight.
The claim as recorded
In the 1978 reference design's mass statement, "power distribution and control" hardware totals 5.863 million kg (1.347 million kg for the collector array plus 4.516 million kg for the antenna section), about 19.2% of the 30.47 million kg total SPS dry weight.
Scope and limits
This is a 1978 paper point design, not a built or flown satellite, and not a mass fraction for any present-day SBSP concept. It excludes the 25% growth margin applied elsewhere in the same table (which would change the fraction only if growth is not applied uniformly across subsystems, which the table does not show). The raw text layer of SRC-085 p.237, Table R-5, corrupts several digits. The figures in this record were read from a rendered image of the page, not from extracted text. A reader who copies the text layer of that table may get different numbers, and the difference is the extraction, not the source.
What it assumes
The table's subsystem boundaries (what counts as "power distribution and control" versus "power source" or "structures") are applied consistently between the array and antenna sections.
Where it comes from
p.237, Table R-5 "Photovoltaic Point Design Mass Statement": Collector array "POWER DISTRIBUTION & CONTROL" = 1.347 million kg; Antenna section "POWER DISTRIBUTION & CONTROL" = 4.516 million kg; "TOTAL SPS DRY WEIGHT" = 30.47 million kg. (1.347+4.516)/30.47 = 19.24%, computed here from the table's own figures.
Basis: 5 GW GEO photovoltaic point design, Table R-5 mass statement, dry mass excluding 25% growth margin
Related records
- Answers question
- QST-002 not published in this release
Cite this
energyaperture.com/c/clm-0212
CLM-0212, Energy Aperture, as of 1978.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-085
- CLM-0013The paper that modern UK studies rely on for the beam figure calls anything below 1 kilowatt per square metre safe, with 230 watts per...CLM-0020The original 1978 design set the beam at 230 watts per square metre in the middle of the receiving site, about one twenty-third of that at...CLM-0023In the 1978 reference design, two limits set the size of the transmitter and the receiving site: how much heat the transmitter can shed...CLM-0039The 1978 report set the figure to protect radio and navigation systems from a disturbed ionosphere, called the number theoretical and...CLM-0045The apparent conflict between 12 and 23 was not an error. The underlying study gave a range, and the figure adopted sits near the top of it.CLM-0101The 1978 contract required the researchers to report fixes if ionospheric disturbance pushed the pilot-beam phase error past 2 to 3...CLM-0137In four major space solar power studies from 1978 to 2007, none put a number on how much of the beam's energy would be lost if the beam...CLM-0138The original 1978 government design for beaming power down from space adds up all the expected energy losses to get 63% overall efficiency...More on the source page.