Value chain · CLM-1102
In plain terms
The receiving station the siting maps were drawn for is an oval twelve kilometres wide and, in the middle of the United States, sixteen long once its safety margin is added, about 150 square kilometres, with two and a half million panels on it; further north it gets longer because the satellite sits lower in the sky.
The claim as recorded
The 1980 siting study describes the reference rectenna site it maps for: an elliptical field about 13 km by 9 km at the 35 deg N reference latitude, of "2.5 million panels" "3 meters high and 10 meters wide" with about "3000 dipole/diode elements" each, in rows "spaced approximately 4 meters apart" with 6 m roads, feeding "125 converter stations", 25 collection/transmission stations and "five step-up switching stations"; a buffer zone "approximately 1 km wide along the perimeter" that NASA correspondence specified to bring exterior densities "to 0.1 mW/cm2 or less"; site dimensions with buffer of 12.0 km east-west at every latitude and north-south 12.0 km at the equator, 13.8 at 25 deg, 14.6 at 30, 15.8 at 35, 17.4 at 40, 19.4 at 45 and 22.2 at 50 (Schwenk memorandum, 1979); so that a site at 35 deg N is "12.0 km X 15.8 km" with buffer, "148.9 km" squared, "(36,800 acres)", and the study's round figure is "more than 15,000 hectares (38,000 acres)" per rectenna.
Evidence behind this: T3-the siting study's own description of the reference rectenna site, from the 1978 reference system, a 1979 NASA memorandum and a 1980 environmental report.
Scope and limits
A SITING STUDY'S RESTATEMENT OF THE DESIGN, NOT THE DESIGN DOCUMENT; the panel count and elements per panel are round. The buffer is set by an exterior limit of 0.1 mW/cm2 that the reference system itself did not specify ("the reference system did not specify the need for or the size of a buffer zone", normalised, PDF 38). Dimensions are with buffer; the field alone is 13 x 9 km at the reference latitude.
What it assumes
The 1978 reference system's 5 GW rectenna; the "Schwenk memorandum, 1979" for the latitude table is not held.
Where it comes from
PDF 37 / printed 28, raw: "2.5 mi1lion panels" (layer's l for 1); normalised: "3 meters high and 10 meters wide", "3000 dipole/ diode elements", "spaced approximately 4 meters apart"; raw: "125 converter stations", "five step-up switching stations"; normalised: "approximately l km wide along the perimeter" (layer's l for 1); the 13 km by 9 km ellipse and the 75 to 80 per cent transparent steel mesh ground plane are render readings of the same page. PDF 38 / printed 29, render read: "subsequent NASA correspondence has specified the use of a buffer zone to reduce exterior microwave power densities to 0.1 mW/cm2 or less" (normalised); the latitude table as listed; raw: "12.0 km X 15.8 km", "148.9 km", "(36,800 acres)". PDF 10 / printed 1, normalised: "The ground receiving station (rectenna) for each satellite will require more than 15,000 hectares (38,000 acres) of land"; "Each grid cell corresponds to a 7.5 minute quadrangle and measures approximately 13 kilometers square". Arithmetic on the stated figures: pi/4 x 12.0 x 15.8 = 148.9 km2 and 148.9 km2 x 247.1 acres/km2 = 36,800 acres, as printed; 15.8 / 12.0 = 1.32 against 1 / sin(49.3 deg) = 1.32 for the GEO elevation at 35 deg N on the satellite's meridian, and 22.2 / 12.0 = 1.85 against 1 / sin(32.7 deg) = 1.85 at 50 deg; 2.5 million x 3,000 = 7.5 x 10^9 elements; 2.5 million x 30 m2 = 75 km2 of panel.
Basis: km of site dimensions with buffer, by latitude; km2 and acres; panels and elements per site
Related records
- Answers question
- QST-007 not published in this release
Cite this
energyaperture.com/c/clm-1102
CLM-1102, Energy Aperture, as of 1980-04.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-565
- CLM-1103Mapped at the scale of one receiver per cell, two-fifths of the country was not ruled out; look closer and seven in ten of those cells fail...CLM-1104The siting maps kept receivers 150 km from radio telescopes, 100 km from NASA's deep-space stations, 60 km from air traffic radars and 50...