Value chain · CLM-1476
In plain terms
The European study states that it used a 3 per cent interest rate for the cost of the space solar satellites. It does not say, in the paper itself, what rate it used for wind, solar and the other power sources, so it is not possible to tell from the paper whether space solar was given an easier test than its rivals.
The claim as recorded
The 2025 Joule study of space solar power in a European power-system model prints a discount rate, 3 per cent over a 30-year life, only for its two space solar designs (Table 2). For the other technologies, the main text says capital costs are annualised with a discount rate over each asset's economic lifetime (Equation 1), taken from the PyPSA technology-data assumptions (version 0.9.2) and the supplementary tables. It does not state the rate's value. So the paper's main text does not show whether the other technologies were costed at the same 3 per cent. The space designs' annual fixed costs in Table 2 reproduce at 3 per cent over 30 years to within 0.02 per cent (our arithmetic).
Evidence behind this: T2: peer-reviewed journal paper (SRC-264).
Scope and limits
The supplementary information (Tables S5-S10) and PyPSA technology-data version 0.9.2 are not held, so the rate used for the other technologies is unknown here, and no value is assumed. Table 1 (PDF p.6) gives the other technologies' 2050 annual fixed costs (for example solar 27.68 to 41.74 EUR/kW-year) but not their capital costs or rate, so the rate cannot be backed out. If the other technologies were costed at a higher rate, the comparison would favour space solar. If they were costed at the same 3 per cent, it would not. The paper did not test space solar at 10 per cent (CLM-0374 (low confidence) restates NASA's best case at 10 per cent).
What it assumes
No assumptions are recorded against this claim.
Where it comes from
PDF p.13, Table 2 "Key parameters and costs in models (PyPSA-Eur) for SBSP under baseline and 2050 scenarios", read at a zoom 4 crop: column "Discount rate (%)" reads 3 for all four rows (heliostat and planar, baseline and 2050), lifetime 30 years; annual fixed costs 4,901.65, 7,687.48, 267.87 and 396.59 EUR/kW-year. PDF p.14, read at a zoom 4 crop: "The overnight capital costs are converted to net present costs by applying an annualization factor a, which uses a discount rate r over the asset's economic lifetime n, as shown in Equation 1."; "Further details regarding the cost computation can be found in the supplemental information."; "Assumptions are maintained at github.com/pypsa/technology-data and were taken from version 0.9.2." The same page cites Tables S5-S10 for 2050 technology costs. PDF p.12: SBSP CapEx and FOM are converted "into annual fixed costs using the annuitization approaches and exchange rates" of reference 48. Check (python): annuity factor at 3 per cent over 30 years 0.05102; CapEx x factor + FOM gives 267.89, 396.55, 4,901.67 and 7,686.48 against the printed 267.87, 396.59, 4,901.65 and 7,687.48.
Basis: per cent discount rate; EUR/kW-year annual fixed cost as printed.
Related records
- Answers question
- QST-021 not published in this release
Cite this
energyaperture.com/c/clm-1476
CLM-1476, Energy Aperture, as of 2025-09.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-264
- CLM-0286A 2025 peer-reviewed study modelled space solar power inside a detailed model of Europe's future electricity system, using the more...CLM-0843Other research groups around the world are publishing on space solar power, but none of the works this search found takes a position on the...CLM-1429A search on 13 October 2026 found no published model of Britain's power system that is free to decide how much space solar power to build...
- Cited in articles