On Wed, 11 Feb 2009 17:30:18 +0000, Grimly Curmudgeon wrote:

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Dave Plowman (News)"
saying something like:

Sounds like a right load of ********.

Think there is something in it - but all good quality batteries are
calcium types these days anyway.

The problem then is the need to keep a calcium battery properly up
without substantially shortening the lives of the vehicle lamps. There
would be very little leeway in it and the slightest wander of the
voltage control would be popping bulbs - which is what seems to be
happening. So much for progress.
Of course, every lighting circuit could be individually or collectively
voltage protected, but that would add a significant cost.

There were certainly plans to utilise a 36V system (although it was to be
referred to as a 42V system), the higher voltage meaning lower losses for
the high power consumers, allowing thinner (lighter) wiring, smaller motors
and powerful, fast starters - permitting engines to be shut off when
stationary. 36V is as high as they could go while keeping peak voltages on
the ac side to around the 50V considered safe for dc systems that people
may come into contact with. This would of course require various voltages
for different systems, but was considered to provide a useful fuel saving.
Apparently the idea was killed off by the difficulties of switching higher
dc voltages without erosion of the switch contacts and by the prospect of
much higher voltage hybrids with inverters and ac drives.

SteveW