Re: H2

[sampere <sampere@PHYSICS.SYR.EDU>]

That may be true, but the cost for that is included in the cell.  That's
why you won't see crystalline Si cells in  widespread use and that's
where the amorphous silicon folks have an advantage.  True, amorphous
silicon cells are not as efficient, but you can make them on any
substrate - glass, stainless steel, etc.  These are the cells that
you'll be seeing on rooftops and remote power stations.  These guys are
making efficiency progress quickly.  The original cells had one
junction.  The current state of the art is triple junction - one layer
absorbs blue, the next green, the last red.  Then the unabsorbed is
reflected back through the cell and given another shot at being
absorbed.  Pretty cool stuff.  Guess which layer is on top.

Sam

Jim Green wrote:

> > Low compared to what?  Compared to, say, electricity from
> > gasohol from corn, solar photovoltaics are efficient.
> > Solar-powered steam engines are comparably efficient
> > (indeed arguably more efficient) relative to photovoltaics,
> > and can produce power overnight.
>
> Well, maybe in the distant future, but for the present it requires much
> more energy to pull a single crystal silicon boule than the wafers derived
> therefrom can produce power from voltaics over their lifetime.  Not even
> counting the power required to manufacture the voltaic per se.
>
> Likewise it looks to me that H fuel is a waste of time.
>
> But I truly would like to be tutored re a future that has some hope.
>
> Jim
>
>
> Jim Green
> mailto:JMGreen@sisna.com
> http://users.sisna.com/jmgreen