Tom Anderson wrote:
On Tue, 26 May 2009, Theo Markettos wrote:

Or something similar. Basically, at the point at which everyone switches
their kettles on, cars across the city stop charging for five minutes, and
resume once the tea is brewing.

It is, but it is not (quite) beyond the wit of man. I think you're
suggesting something along the lines of what i suggested above, but
cleverer.

Yes, that's the sort of thing I was getting at. It would have to be
carefully designed to avoid this kind of thing:

Night electricity cheap
Everyone's car is set to come on charge at 2am when electricity is cheap
Power surge, electricity expensive
Everyone's car switches off
Load dip, electricity cheap
Everyone's car switches on
etc, repeat as fast as the network can switch

At which point you've not only fried the car charging electronics, but
potentially fried the generating plant too. When there are millions of
demand-sensitive devices, the control system gets very complex. As you also
have to worry about keeping the network synchronised at 50Hz.

Not exactly a piece of cake to design, but it's not beyond the laws of
physics so it's possible.

Theo