Re: [tlug] silicon cash eater

[Curt Sampson <cjs@example.com>]

On 2017-06-23 22:47 +0900 (Fri), kts wrote:

> I suppose before any change it would be good to source a power meter
> and see if this machine is really the culprit for excess power
> consumption.

Um, yeah. :-)

Someone tell me if there's an error in the following calculations.

Looking at the Tepco rate sheet[1], home electricity seems to run
¥30.02 per kWh once you're at step 3, which is where you'll be in most
cases unless you live in a one-room and are really economical with the
aircon/danbou. (I am such a person. With 30 A service my crossover
point from Stage 2 to 3 is ¥7865; my bill is under that less than half
the months in the year.)

So let's look at the power reduction we can get if we replace a PC
that idles at 150 W (which is huge for an idling PC, I think) with one
that idles at 50 W.

    100 W * 730 h/month = 73 kWh/month * ¥30.02 = ¥2191

Not a totally trivial saving, if you can really save that much
electricity, but the return of ¥52,584 over two years (less interest)
is not going to pay for all that much of a PC.

I need to get an ammeter clamp so I can start measuring my PCs.

[1]: http://www.tepco.co.jp/en/customer/guide/ratecalc-e.html

cjs
-- 
Curt Sampson         <cjs@example.com>         +81 90 7737 2974

To iterate is human, to recurse divine.
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