This is not to say that alternative power is a bad thing. It's just not
yet advanced enough for high power industrial applications. Solar powered
level crossings, signals and communications are viable and are
particularly suited to Australia. Even on cloudy days there is enough
electricity generated to keep the system running. The solar panels I've
seen in Queensland powering such equipment is not very big, only about 1
metre square.
Interestingly, I have experienced an unintended demonstration of the
viability of solar hot water for railway purposes. In December 1992 I had
a day to kill in Mt Isa when I travelled on the Inlander. On this
particular day it was 45 degrees in the shade and the train had been
standing in the sun all day. Even after sunset the cold water in the
sleeping car was hotter than the hot water. The wonders of roof tanks. :)
>Heating water for domestic use and commercial low powered DC
>applications are a reality, anything else at this point in
>time will have to wait.
There is enough space on the average suburban house roof to generate
enough electricity to run most household items, except for maybe the
largest of rereigerators. For domestic use, solar is fine.
Solar thermal electricity has some merit is a supplement other power
stations.
Looking back on my calculations, there may be as much as 450 square metres
of roof space available on a 2+8 train. In theory you could get 150kW from
the roof on a sunny day. It might be enough to _supplement_ the auxiliary
power, such as lighting and air conditioning. This is, of course, assuming
the roof is kept clean.
Cheers
David