🚀 go-pugleaf

Dan Mills <Dmills@abcde.demon.co.uk> wrote:


>The silicon PV tecnology takes more energy to produce then it
>can produce over the lifetime of the cell.

This was certainly true of ealry Crystaline Cells, it is certainly
untrue of even current generation Crystaline.  If you doubt, do a
simple calculation, take the stated output of the cell, multiply it by
the stated lifespan, which calculation will give you the total output
of the cell - multiply this by the wholesale cost of electricity
(typically 20% of retail), and compare it to the wholesale cost of the
cells (typically 50% of retail).   Today most show a clear profit.

The key thing with PVs is that the future lies not with crystaline
cells, but with amorphous cells.  Workers in Sydney Australia have
produced 5micron cells with 15% efficiency.   Theoreticaly we should
be able to get to 0.5 micron eventually.  I'd guess we'll see
commercial 2 micron cells around the turn of the century.

Using such thin film, the payback times are incredible - under a month
should be possible by the end of this decade.

It isn't here yet, and we definitely shouldn't waste any effort on
large scale production of Electric Vehicles until it is.  But it is
coming, and is an option to fision.   Fusion is still a dream, but one
worth spending a little time on.

My personal bet is amorphous PVs for humanity's power for the next
couple of centuries.  Deserts from Saudi, USA, Mongolia, Egypt, &
Australia, could supply enough energy for the entire population of the
planet to enjoy a lifestyle consuming twice the energy that the USA
does currently.  Allowing for increasing efficiencies at all levels of
production, that equates to a very comfortable lifestyle ;-)

I'll also bet that we keep Internal Combustion engines for many
transport applications, but they are likely to be banned in cities,
where the density of traffic makes electric reticulation economic.

If one looking to space, the future lies in thin film mirrors,
diffraction gratings, and limited PVs.   The economics of it will
ensure that it happens reltively soon (within 30 years) - not with
mass launched from the earth (that's too expensive) but with mass
launched from the moon.

Happy New Year