Value chain · CLM-0692
In plain terms
The Chinese design's own summary table adds up: the parts weigh what the total says they weigh. Its claimed 12.3 per cent efficiency is sunlight-to-grid, which checks out against the area of the panels and the strength of sunlight in space. The antenna is a long thin strip, 100 metres by 10.5 kilometres, at 5.8 gigahertz.
The claim as recorded
CAST's 1 GW MMR-SPS summary is internally self-consistent on the checks available: total mass 9,160 t equals the sum of its four subsystem masses exactly (solar 1,800 t, microwave power transmission 4,200 t, power transmission and management 1,360 t, other 1,800 t); and its stated "total efficiency ~12.3%" is confirmed independently as a sunlight-to-grid figure, since 6 km2 of array at a 1,361 W/m2 solar constant intercepts 8.17 GW and 1 GW delivered is 12.2 per cent of that. Other stated parameters: GEO, 5.8 GHz, wireless transfer efficiency ~54 per cent, PV cell efficiency ~40 per cent, array output ~2.4 GW, transmitting antenna 0.1 x 10.5 km, 50 antenna subpanels at 32 MW each, main bus 5 kV, 100 rotary joints.
Scope and limits
The text layer of this PDF is corrupted and these figures were read from a rendered image for that reason - the text layer gives 5.8 as "S.8", 50 as "so", 2.4 as "-2A" and 0.1x10.5 as "0.1K10.S". Any further figure taken from this source must be image-read. The 12.3 per cent sunlight-to-grid efficiency is a design target, not a measurement. The 32 MW per antenna subpanel is microwave power radiated, not array output: the paper's text (PDF pp.4-5, printed 110-111) gives 48 MW DC per module, 50 x 48 MW = 2.4 GW, then 89 per cent to each antenna subpanel (42.7 MW) and 76 per cent from DC to microwave (32 MW), so 50 x 32 MW = 1.6 GW radiated toward Earth.
What it assumes
solar constant 1,361 W/m2 at 1 AU; that "total efficiency" means sunlight-to-grid, which the arithmetic supports rather than assumes.
Where it comes from
Subsystem mass sum 1800 + 4200 + 1360 + 1800 = 9160, matching the stated total. 6e6 m2 x 1361 W/m2 = 8.17 GW incident; 1 GW / 8.17 GW = 12.2 per cent against the stated ~12.3. Array output 2.4 GW is 29.4 per cent of incident against a 40 per cent cell efficiency, the balance being packing factor and losses. 2.4 GW x 54 per cent wireless efficiency = 1.30 GW at the rectenna, of which 1 GW reaches the grid, a 77 per cent rectenna-to-grid figure.
Related records
- Answers question
- QST-022 not published in this release
Cite this
energyaperture.com/c/clm-0692
CLM-0692, Energy Aperture, as of 2025.
Connected records
Other published records linked to this one. A list, not a judgement.
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