Value chain · CLM-0601
In plain terms
In one model, swapping refuelling flights for electric-propulsion tugs cuts the electricity cost by about two thirds. NASA's own analysis reports 62 per cent total cost savings for its electric-propulsion variant, and a critic said that using tugs with electric propulsion would be a far more efficient approach. The three are not fully independent, because the model uses NASA's own inputs.
The claim as recorded
Three routes, not fully independent, agree that replacing tanker refuelling with electric-propulsion orbital transfer removes most of the cost: a named critic identified it as the correction NASA should have made, NASA's own sensitivity analysis reports 62 per cent total cost savings for its electric-propulsion variant, and the model at CLM-0410 finds levelised cost falling from 0.6231 to 0.2069 USD per kilowatt hour, a 67 per cent reduction, once refuel launches are removed and a 17.2 per cent mass penalty applied.
Scope and limits
This does NOT close the cost gap on its own. 0.2069 USD/kWh remains four to ten times the 0.02-0.05 terrestrial comparator. It falls inside the 0.027-0.253 span of the register's firm-generation figures only because that span runs from nuclear life extension (CLM-0462) to microreactors (CLM-0469); it is above CLM-0469's large-nuclear range of 0.049-0.137. It removes the largest single term; it does not make the economics competitive. The three routes are also not fully independent: the model was built from NASA's own inputs, so agreement with NASA's sensitivity is partly structural.
What it assumes
that the 17.2 per cent mass penalty for electric propulsion is correct. CORRECTED 2026-09-03: this field previously said the figure "is not independently sourced". It is. The 17.2 per cent is NASA OTPS's own published figure at SRC-012 p.90-92, a first-order delta-v calculation using NASA's real NEXT-C thruster and an assumed >4,700 m/s LEO-to-GEO requirement. An independent rocket-equation check gives 10.8 per cent for propellant alone at NEXT-C's maximum specific impulse of 4,200 s, which is consistent with 17.2 per cent for propellant plus hardware. See CLM-0664 and CLM-0665. The correction weakens this claim's own hedge and strengthens the claim, which is the direction a correction least often runs
Where it comes from
This is the project's own working, shown in full:
The Space Review 2024-02-05 quotes the critic saying "using tugs with electric propulsion would be a far more efficient approach". SRC-012 PDF p.91 (printed p.74): "62% total cost savings for the Innovative Heliostat Swarm". Own model Section 7: electric propulsion scenario gives 0.2069 USD/kWh against a 0.6231 baseline, a delta of 0.4162.
Basis: USD/kWh, NASA 2024 basis, 3 per cent discount rate
Related records
- Answers question
- QST-004 not published in this release
Cite this
energyaperture.com/c/clm-0601
CLM-0601, Energy Aperture, as of 2026-09.
Connected records
Other published records linked to this one. A list, not a judgement.
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