Talk:Nanofactory engineering/power supply

From Wise Nano

Discuss the power supply (probably solar cells) needed by a nanofactory. As conclusions are reached, put them in Nanofactory engineering/power supply.

Diamond thermionic?  by Brett Bellmore 20:19, 28 Sep 2004 (CDT)

These cells do show a great deal of potential, but do have a downside: Thermionics work at high temperatures, achieved by *focusing* sunlight to a high degree. I don't doubt the capacity of nanotechnology to build sun tracking parabolic mirrors, but you can only focus sunlight to that extent on clear days. On cloudy days, with diffuse sunlight, thermionics are severely limited. Photovoltaics work better in climates where cloud cover is a common event, and are theoretically capable of comparable efficiency.

Unfortunately, while you can build thermionic systems out of diamond, diamond's band gap is not particularly suited to photovoltaics, unless other elements are involved. I see several potential responses:

1. Live with it. Large sections of the world ARE well suited to use of thermionics, after all.

2. Add the capacity to handle silicon and aluminum, in addition to carbon. Use of these common elements, (Far more plentiful than carbon, to be sure!) would permit the construction of amorphous silicon solar cells, which can fuction effectively in extremely thin films. And you want to be able to produce silica and saphire anyway, for those applications where diamond would be excessively prone to catching fire.

3. Build diamondoid mechanisms capable of manufacturing high efficiency non-diamond solar cells by more conventional processes such as sputtering. This might be worth doing in any case, given the high energy consumption of the assemblers per unit of mass processed, compared to more conventional processing.