CLM-0015 - Energy Aperture

In plain terms

An independent Japanese authority on power beaming records the American reference design's beam strength as 23 milliwatts per square centimetre at the receiving site, which is 230 watts per square metre.

The claim as recorded

Shinohara's parameter table for the NASA/DOE SPS model gives 2.45 GHz, a 1 km diameter transmitting antenna, a 10 dB Gaussian amplitude taper, 6.72 GW beamed to Earth, a maximum rectenna power density of 23 mW/cm2 which is 230 W/m2, and a collection efficiency of 89 per cent.

T2 peer-reviewed analysis, model or thesis · medium confidence · as of unknown · VER-681 CONFIRMED 2026-09-04 · VC05, VC06, VC07

Scope and limits

Second-hand to the 1978 primary document, which is SRC-085. CORRECTED 2026-09-06: that document IS acquired and held; the statement that it was not had gone stale. Undated draft, so asof is unknown, which is itself a defect in this source. The table's rectenna diameter column did not extract reliably and is NOT recorded here rather than guessed. CONDITION MOVED HERE FROM `notes` 2026-09-05 by ruling, because `notes` is dropped at publication and a restriction there reaches nobody: this figure is NOT the ground power density profile and must not be used to infer the beam edge value at the rectenna. Conflating the two is exactly the error this question exists to avoid. The 89 per cent collection efficiency is most likely a transcription of the 1978 reference document's own figure (SRC-085 states 89 per cent in two efficiency chains and 88 in its text for the same aperture, CLM-0869), so this record and SRC-085 count as one source on that figure, not two in agreement.

What it assumes

that the fourth column of Table 1.1 is the NASA/DOE model, as its header states

Where it comes from

SRC-082 Wireless Power Transmission for Solar Power Satellite (SPS), second draft, unknown

Table 1.1, NASA/DOE model column, verbatim fragments: "Frequency ... 2.45 GHz", "Diameter of transmitting antenna ... 1 kmφ", "Amplitude taper ... 10 dB Gaussian", "Output power (beamed to earth) ... 6.72 GW", "Maximum Power Density ... 23 mW/cm2", "Collection Efficiency ... 89 %". Conversion: 23 mW/cm2 x 10 = 230 W/m2.

Related records

Answers question: QST-001 not published in this release

Cite this

energyaperture.com/c/clm-0015

CLM-0015, Energy Aperture, as of unknown.

Connected records

Other published records linked to this one. A list, not a judgement.

Also from SRC-082: CLM-0017One author, writing in an unpublished draft, says the exposure guideline must be met outside the receiving site, and that what applies...