Value chain · CLM-0177
In plain terms
The cost model assumes the satellite gets cheaper to build the more of them are made, using a range that runs from the faster cost-learning of a 2010s space-industry estimate (Mankins) down to the slower cost-learning the study estimates for SpaceX's Starlink constellation; separately, it assumes the system generates power 100% of the time with zero downtime, which the study's own authors call optimistic.
The claim as recorded
The Frazer-Nash cost model assumes a triangular-distributed learning exponent for mass-production cost reduction of -0.73 to -0.24 (mode -0.58), based on John Mankins' estimate that SPS satellite cost/kg falls to 67% of the prior value for each doubling of production volume (a roughly 33% learning rate) at the mode, bounded above by the document's estimate that the mass-produced Starlink constellation reduces to 85% of cost per doubling (a roughly 15% learning rate), which is the SLOWEST learning in the range and therefore its least optimistic end; separately, the model's "Load Factor" (capacity factor) is fixed at a constant value of 1 (i.e. 100%), which the same document describes as "a design assumption" that "is slightly optimistic, as there will be some downtime for shadowing by the Earth and maintenance, but these are likely to be relatively small".
Scope and limits
Capacity factor is not empirically demonstrated for any GEO SBSP design; it is a stated simplification. The learning-rate range spans a very wide band (15%-33%+ per doubling) which is itself a major source of the LCOE uncertainty shown in CLM-0170. The 85% Starlink figure cannot be traced within the document: its citation [44] resolves in the bibliography (p.15) to a 1997 US patent on re-orbiting a geostationary spacecraft, and the only Starlink item in the bibliography ([23], p.14) concerns the user terminal.
What it assumes
SPS module manufacturing follows an industrial learning curve comparable to either aerospace (Mankins) or satellite mega-constellation (Starlink) production; capacity factor of 100% is achievable or near-achievable for the specific orbit/design chosen.
Where it comes from
"John Mankins has estimated that the cost/kg of SPS satellites reduce to 67% of the original cost for each doubling of production volume" (PDF p.8; the page then gives 2^fLC = 0.67, so fLC = -0.58). "A range of remaining costs after a volume doubling of 60-70% is given" (same page), "leading to fLC of -0.51 to -0.73." "The mass-produced Starlink constellation is estimated to reduce to 85% of cost each doubling of production" (same page), "leading to fLC of -0.24." Table B1 gives the Learning Exponent as a Triangle distribution: -0.73 / -0.58 / -0.24 (p.8, p.4). "Load Factor... Constant... 1" and "Load factor is a design assumption. This is slightly optimistic, as there will be some downtime for shadowing by the Earth and maintenance, but these are likely to be relatively small" (Table B1 row p.3; justification p.6).
Basis: dimensionless (learning exponent / capacity factor), 2021 vintage
Related records
- Answers question
- QST-041 not published in this release
Cite this
energyaperture.com/c/clm-0177
CLM-0177, Energy Aperture, as of 2021.
Connected records
Other published records linked to this one. A list, not a judgement.
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