Value chain · CLM-0111
In plain terms
An authoritative 2013 review says the 230 watt per square metre figure was chosen early in the design as a cautious maximum. It does not describe it as a measured or derived limit.
The claim as recorded
A 2013 review in the Proceedings of the IEEE states that the 230 watts per square metre power density was SELECTED as the maximum level to avoid strong interaction with the ionospheric plasma during the early stage of the space solar power satellite design.
Evidence behind this: T2-review. The claim itself is one quoted characterisation from SRC-127 page 1442 section E. The uniqueness statement that stood in limits until 2026-09-10 was never searched, and the search that should have supported it was run on that date: every record in the claim register whose claim names 230 W/m2 or 23 mW/cm2 together with a word of selection, origin, basis, derivation, choice, threshold, proposal or criterion. It returned 24 records, of which four state a REASON the figure was adopted - and those four reasons differ, which is why the statement was withdrawn rather than qualified. This is a search of the register and not of the literature: it establishes what is held here, not what exists.
Scope and limits
A review's characterisation, not a primary design record. It does not say who selected it or on what date, and it does not cite a source for the selection. It is nevertheless an authoritative modern account: Proceedings of the IEEE, lead author from JAXA. THE ORIGIN OF THE 230 W/m2 FIGURE IS CONTESTED, NOT MERELY UNDER-DOCUMENTED. At least four accounts of why it was adopted are held and they do not agree with each other. SRC-127, here, says it was selected to avoid strong interaction with the ionospheric plasma. SRC-026 describes it as an optimum peak beam intensity chosen on ECONOMIC grounds (CLM-0004). SRC-142 states it is proposed as a human and environmental EXPOSURE safety cap (CLM-0148). SRC-141 calls it a theoretically derived critical value for the onset of nonlinear effects (CLM-0149). The 1978 Reference System's own statement of the ionospheric basis sits at SRC-085 (CLM-0039). Anything drawing this figure's provenance must show the disagreement rather than resolve it, and that includes a timeline. The search behind this finding is stated in tier_detail.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
page 1442, section E Ionospheric Interaction, verbatim: "One of the essential concerns about the microwave power transmission from space is the possible nonlinear interaction of the high-power microwave beam with the ionosphere. The power density of 230 W/m2 was selected as the maximum level to avoid strong interaction with the ionospheric plasma during the early stage of the SPS design."
Related records
- Answers question
- QST-001 not published in this release
Cite this
energyaperture.com/c/clm-0111
CLM-0111, Energy Aperture, as of 2013-06.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-127
- CLM-0112The same review says modern work finds about 1 kilowatt per square metre acceptable at 5.8 gigahertz, more than four times the older...CLM-0113As of 2013 the experiment needed to check these predictions had still not been done.CLM-0128A 2013 review gives three references for the 1 kilowatt per square metre figure: two Japanese papers from 1995 and 1996, and a 1981 paper...CLM-0133A 2013 review paper says calculations suggest a stronger microwave beam than the usual safety limit would still be fine at a higher...CLM-1467 (low confidence)Keeping people out of the area where the beam is strong is a plausible way for a strong beam to meet the 2020 international limit for...