Re: [tlug] silicon cash eater

[kts <kts@example.com>]

There we go, thanks for the calculations. The simple fact is out of habit I leave my main PC, the i7 running SETI, on 24/7.

Now I have an inefficient 6-core running pretty idle but with 6 drives, a left-over high power PSU, running 24/7.

According to your calculations, call it my ¥4,000/month silicon cash eaters. So my bad habit of letting i7 idle when not using it is pure waste, and costing me unnecessarily. The home server while inefficient is serving a purpose. Excuse me while I go shut down the w10 machine---

Regards,

Kevin Sullivan

JP +81-90-9829-9653

kts@example.com

On Jun 26, 2017, at 21:35, Curt Sampson <cjs@example.com> wrote:

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