Value chain · CLM-0933
In plain terms
In 1988 the leading experimenter listed three numbers side by side: the best efficiency physics allows for beaming power and converting it back, 76 per cent; an experimental figure, 54; and what a solar power satellite design assumes, 58 to 72. The design range is above the experimental figure, and its top end is close to the limit.
The claim as recorded
A 1988 viewgraph by the man who ran the microwave power transmission experiments puts the assumed SPS efficiency, 58-72%, above the slide's 54% experimental figure and below its 76% maximum. Three figures on one slide: "MAXIMUM POSSIBLE DC TO DC EFFICIENCY --- 76%", "EXPERIMENTAL DC TO DC EFFICIENCY --- 54%", "SOLAR POWER SATELLITE EFFICIENCY --- 58-72%". So the design assumes an end-to-end efficiency between four and eighteen points better than the slide's experimental figure, against a ceiling of 76. The stage chain on the same slide reads DC-to-microwave conversion 70-90 per cent, beam-forming antenna 70-97, free-space transmission 5-95, reception and conversion to DC 85-92.
Evidence behind this: NASA conference publication, viewgraph proceedings. The three labels and the three values are separated in the text layer and the PAIRING IS A RENDER READING - see limits. Labels and values are each confirmed present in the text layer, in matching order.
Scope and limits
THE LABEL-TO-VALUE PAIRING IS NOT IN THE TEXT LAYER AND IS READ FROM THE RENDERED PAGE. The extractor emits all three labels and then all three values as separate runs, so anyone matching on the text layer alone could attach the wrong number to the wrong label. Labels and values are each confirmed present and in matching order; the correspondence is a render reading and is not claimed as a text-layer fact. THE STAGE CHAIN IS WORSE AND NO CHAIN FIGURE IS RECORDED HERE: the layer renders 70 as "7n" and as "lO", which is the letter-for-digit class, so those four ranges are reported as read from the page and must not be quoted from extraction. A VIEWGRAPH, NOT A PAPER. No method, no measurement conditions, no frequency and no aperture are attached to any of the three figures on that slide, and "EXPERIMENTAL" is not sourced to a named demonstration. 58-72 is a range spanning fourteen points and the document does not say what moves it. 1988, and nothing here establishes any efficiency achieved since.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
Read first-hand on registration. The labels are present in the text layer in this order: "MAXIMUM POSSIBLE DC TO DC EFFICIENCY EXPERIMENTAL DC TO DC EFFICIENCY SOLAR POWER SATELLITE EFFICIENCY", immediately followed by "--- 76% --- 54% --- 58-72%". The stage chain precedes it as "CONVERSION | CONVERSION ANTENNA TRANSMISSION | TO DC | 7n - 90 % lO - 97 % 5 - 95 % 85 - 92%". A59 CONTROLS FROM THE SAME EXTRACTION: rectenna 28, microwave 40, efficiency 34, magnetron 5, "2.45" 7.
Basis: per cent (DC-to-DC efficiency)
Related records
- Answers question
- QST-002 not published in this release
Cite this
energyaperture.com/c/clm-0933
CLM-0933, Energy Aperture, as of 1988.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-417
- CLM-0934In 1988 the NASA centre running the work said the solar power satellite programme did not stop because the technology failed. It stopped...CLM-0940Two NASA efforts to build rectennas at much higher frequencies than the standard 2.45 GHz ended without a working device. One concluded the...
- Contradicted by
- CLM-0938A 1988 NASA paper says a rectenna built on mylar reached 85 per cent efficiency. The 1987 final report of the contract it cites says mylar...