Construction of this solar array demonstrates the re-use of the United States Space Shuttle external tank as a raw material resource in building large scale space platforms on orbit. Presently, the tank is jettisoned during ascent and the residual fuel vented, tumbling the tank as it descends to ensure its breakup and safe destruction due to entry heating. The tank re-enters the earth atmosphere and is vaporized, with only small debris surviving re-entry and falling into the Indian Ocean.
The use of the tank's structure as raw material, rather than a structure in and of itself, necessitates an "orbital factory" that is capable of converting the tank in its present form into one that is suitable for use in a microgravity environment. The tank's skin, 2 inches thick in places, is over-designed for on-orbit use. Here, we only need thin aluminum, properly shaped, to withstand low acceleration forces in building large scale structures.
The factory is a three node unit operating much like the American Colonialist's apple peeler, hence the title. It consists of a drive wheel, a scrubber that removes and recycles the insulation and solar furnace powered by the Large Deployable Reflector. The Sun's powerful light, unhindered by the atmosphere, is concentrated and focused by the LDR and trained on the exposed tank skin as the tank rotates beneath the beam. A glowing ribbon of molten aluminum is peeled off with each rotation and transferred to the extrusion jaws of a Composite Beam Builder, producing a one piece structural tower in a continuous stream. Cold to cold in one operation, using only as much of the tank at one time as is needed.
In the distance, a Tank Farm Station houses the crew and provides temporary storage for tanks awaiting processing. External tanks have a low weight to size ratio and will deorbit fairly quickly if left to their own devices. Corralling them in one spot increases this ratio, keeping them up there, and also clears the orbit of a few 17,500 MPH buildings flying around that one must keep an eye out for. Small space tugs deliver tanks from the farm to waiting factories and a Composite Beam Builder in the Space Shuttle payload bay supplies smaller cross beams for the array.