On 08/04/16 17:14, whisky-dave wrote:
On Friday, 8 April 2016 16:46:11 UTC+1, Tim Watts wrote:
On 08/04/16 14:23, whisky-dave wrote:

No it isn't and it's already been done with E7.

Nothing like the same problem. The E7 simply records the whole house's
consumption and switches the recording to a different meter for a
specified period (be it time based or radio-switched).

You can plug anything into the main but yuo won't get the E7 rate until
the meter in yuor house tells you you can.

How exactly is that related to your meter recording how much your car
takes to charge, separated out from all the other load?

The car charging system would know how much current it is taking and hence power, so would send the meter that value, and that's what it would use for evaluating how much to charge you.

And even if you mandate that the car line signals over the mains wiring
to the meter[1], how does that get around:

a) Blocking the signal with filters?

I'm not sure you could do that without being detected.


b) Putting a big UPS in the way and charging that, then using that to
charge the car (tedious perhaps, but nevertheless).

Might work if you can affod the UPS, I have one here beeping in teh lab at me, they aren't cheap. it'd cost £1000s.


The only sensible idea is mandating the meter is built into the car
itself.

It will need that anyway to regulate the charge.

All this talk of somehow making the main house meter record "car
taxable" and "non car" consumption is nonsense. It's non trivial, too
easy to get around and too costly to implement.

It really isn't that difficult.


Look, the bloody government can't even get "ordinary" smart meters right
with a single standard. How the hell are they going to pull off a stunt
like this?

I think it's you who hasn't thought this through!

it's already being worked on, and really isnt that difficult.
Even the simplest of systems would work, when the meter 'see's a sudden current surge in current as a car battery charging will have that effect, the rest is just simple calcluations.


It might not be "that hard" in a lab.

Neither is coming up with a universal smart meter that all suppliers can
plug forumlaic tariffs[1] into, provides user friendly in house readout
units with facilities for visually impaired users. This particular
scenario seems quite easy to me - but it hasn't happened and probably
won't for a long time, just because it's hard getting a dozen
stakeholders to agree on anything.

[1] Because no one is going to be happy with "simple time based" - they
are going to want their own special blend of ways to charge their
customers - possibly adapting in real time to system load. So you need a
fairly general solution.

Now you are talking about retrofitting smart metering that logs
particular specific loads as well as the grand total plus all the funky
tarrifs, which not only involves all of the above stakeholders but also
has another (by the time they do this) several dozen or more
stakeholders (car manufacturers) - and that's just for cars. Imagine
extending to the socialist's utopia of having remote switching and
charging of various load classes (eg water heating and storage heating
as lowest priority through to "life support" as highest priority).

It's just not going to happen in the real world - not in my lifetime,
just due to the fact there are too many people involved, the government
are proven crap with defining IT standards so they won't just do it
either plus the immense installation base.

You then have to ask the question: Is there an easier way to solve the
problem (tax electric cars). Well, several have been proposed in this
thread that sound vaguely workable with varying degrees of tradeoffs, so
why would anyone proceed with the hardest solution?