In message , at 11:24:41 on Thu,
29 May 2008, Dan Sheppard remarked:
Roland Perry wrote:
I'm surprised a medium factory would take that much power, but the most
difficult part inside the car park is wiring up every bay to the feed.

Surely there are already metal poles in the ground wired for
electricity in many car parks? You'd need thicker cabling to each of
these new "poles", and many more circuits back to a substation, but I
don't think this is going to be as much as a problem as the capacity
issues further up.

I don't recall seeing any. There's the lighting, of course, but that's
orders of magnitude too low capacity for this.

If we give the car 15 Amps at 240V say, for a 200 place carpark,
that's 3000A. Which is about the amperage at which you want to start
considering a dedicated substation, and certainly one where you want
multiple drops.

TNP seems to think a 300 place car park is the same as a small factory,
but I'm sceptical he hasn't dropped a zero somewhere.

Perhaps it would make more sense to feed these poles at, say, 11kV and
give them each 1/3A. You may want to transform that down in each pole,
or else provide a safety interlock in the connector.

That'll be good to stop people stealing the power for their houses, but
doesn't sound very "all weather" to me.

But, why are we doing this again?

So we drive more than 5 miles a day in an electric car
--
Roland Perry