Value chain · CLM-1430
In plain terms
Put in 2024 money, a reliable British grid built on wind, sun and stored hydrogen would cost about 61 to 107 pounds per megawatt-hour in 2050. Set against the top of that range, the UK government's space solar study comes in at about half, and NASA's study, rebuilt in 2024 money, at nearly nine times. The two sides are costed differently, so this is a rough guide, not a like-for-like price comparison.
The claim as recorded
Brought to 2024 pounds with HM Treasury's GDP deflator, the Royal Society's 2050 cost of a Great Britain electricity system run on wind, solar and hydrogen storage is GBP 60.7 to 107.4 per MWh. Against its 10 per cent, high-cost end of GBP 107.4, the restated first-unit space solar estimates at a 10 per cent real discount rate are 0.46 times (Frazer-Nash for BEIS, GBP 49.1/MWh), 0.53 to 1.03 times (Frazer-Nash for ESA, 10th to 90th percentile), 8.66 times (NASA's mirror design as rebuilt, GBP 930.3/MWh) and 16.67 times (NASA's flat-panel design as rebuilt), and NASA's combined-improvements cases are 0.54 and 1.44 times.
Evidence behind this: T0: a restatement computed for QST-021 from published records (CALC-133); not a figure any source publishes.
Scope and limits
A restatement computed for QST-021: indicative positions, not a like-for-like price comparison. It sets a plant's cost per unit, for space solar designs assumed to run for between 60 and 100 per cent of the year, against the cost per unit of demand met by a whole modelled system in 2050 (a modelled case, not a forecast, and not a delivered or retail cost), and counts no backup, eclipse, maintenance or grid cost for space solar, so the space solar side is a lower bound on its system cost. The Royal Society does not say whether its 5 and 10 per cent are real or nominal, and its printed ends do not isolate the rate: GBP 52 pairs low costs with 5 per cent and GBP 92 pairs high costs with 10 per cent. The 10 per cent comparison here sets the space solar figures against the high-cost end, where the bar is at its highest; read from its Figure 24 (p.64), a 10 per cent, low-cost case is about GBP 57/MWh in 2021 prices (about 66 in 2024 prices), against which every multiple is about 1.6 times larger (a chart reading, not a printed figure; CALC-133). Lives are not harmonised: space solar is at a 20-year life chosen by the restatement, the Royal Society at its own asset lives. The Royal Society system leaves out biomass, hydropower, interconnectors and grid location effects, has wind and solar supply about 1.33 times demand, and uses 2040 wind and solar cost projections for 2050 (CLM-1419). Two deflators are mixed: the Royal Society figures are moved with the GDP deflator, and the Frazer-Nash BEIS figures were moved with a recalled UK CPI multiplier 0.19 per cent above the GDP deflator's (CALC-133). The recalled deflators and exchange rates behind CALC-062 and CALC-063 agree with fetched series to within 0.11 per cent (CALC-133). NASA's figures are a rebuild of NASA's study, not NASA's published numbers (CLM-0390); the combined-improvements rows are NASA's own stated best case, stacking five or six improvements (the report's own lists differ; CLM-0124), not a forecast (CLM-0374 (low confidence)). The Frazer-Nash figures use a shortcut restatement that carries about plus or minus 25 to 30 per cent (CALC-061). The space solar figures come from Frazer-Nash's studies for BEIS (2021) and ESA (2022) and NASA's study (2024), for no particular grid and not for one common year: the BEIS study puts both its first unit (SRC-021 PDF p.14) and its costed fifth unit (CLM-0170) at 2040, and NASA's designs run from 2050 (CLM-0662). The designs are assumed to run for all of the year in the BEIS study's model, which its authors call slightly optimistic (SRC-019 p.3 and p.6), 95 to 98.5 per cent of it in the ESA study (CLM-0280), 99.7 per cent for NASA's mirror design and 60 per cent for its flat-panel design (CLM-1349, CLM-0286).
What it assumes
Space solar figures at a 20-year life and 10 per cent real, as restated in CALC-062 and CALC-063; the Royal Society's 10 per cent, high-cost end taken as the comparison point at the same rate.
Where it comes from
This is the project's own working, shown in full:
CALC-133, working and result. CLM-1419: GBP 52 to 92 per MWh in 2021 prices. CALC-062 and CALC-063: the restated space solar estimates. SRC-787: calendar-year GDP deflator 82.7095 (2021) and 96.5672 (2024), 2025 = 100.
Basis: GBP2024 per MWh. Space solar at a 20-year life and 3 or 10 per cent real (CALC-062, CALC-063); the Royal Society range at its own 5 to 10 per cent, not labelled real or nominal, moved from 2021 to 2024 prices with HM Treasury's calendar-year GDP deflator (SRC-787).
Related records
- Answers question
- QST-021 not published in this release
Cite this
energyaperture.com/c/clm-1430
CLM-1430, Energy Aperture, as of 2026-10.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-019
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- Also from SRC-021
- CLM-0170A UK government-commissioned study estimates the cost of electricity from a mature (fifth-built) space solar power satellite at roughly 3.5...CLM-0171The same model shows the cost of electricity is noticeably higher for the first unit built than for the fifth, and when this study compares...CLM-0172The study uses a high assumed rate of return (20%) to work out the headline cost-per-unit-of-electricity figure, but uses a much lower...CLM-0173Developing a working space solar power system for the UK is estimated to cost somewhere between about 7.5 and 16 billion pounds (in 2021...CLM-0174On the study's own numbers, a first space solar power system would not, by itself, earn investors the return they would expect (20%) - it...CLM-0175For every pound of public money put into the whole programme, the study estimates the UK economy gets back between GBP 1.30 and GBP 1.80...CLM-0522The UK study used a 20% return requirement, based on what institutional investors are expected to want. The US study used 3%, on a one-line...CLM-0538The US and UK studies are not just using different toughness levels for the same test -- they are answering different questions. The US...More on the source page.
- Cited in articles