On 01/10/2013 09:37, harryagain wrote:
"The Natural Philosopher" wrote in message
...
On 30/09/13 22:49, Andy Burns wrote:
The Natural Philosopher wrote:

Huge wrote:

Andy Burns wrote:

How much power do you think datacentres gobble up?

Tens of megawatts.

I think that's a little on the high side, megawatts, yes.

3-4MW is about right for each of the datacentres we have servers in,
what fraction of those MW are sipped during the peaks of the sine wave?
How many "big" UK datacentres? 40-50 maybe?


Just about ANY electronics tends to have an SMPS strapped on it. And they
are ALL peak clippers.

It's a huge change from the days when the load on the grid was largely
resistive (lighting) and slightly inductive (electric motors).

Peak currents are much higher than the average..the current waveform is
far from sinusoidal. This leads to far higher losses in the resistive
parts of the grid.


Twaddle.

Yes, but only if by "twaddle" you mean, "yes that is a pretty good
description", then you are right.

Here I drew it for you:

http://wiki.diyfaq.org.uk/images/e/e...simulation.png

The waveform shows voltage at R2 and current through it.


--
Cheers,

John.

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