[time-nuts] Lady Heather on a Laptop

Charles P. Steinmetz charles_steinmetz at lavabit.com
Thu Sep 27 22:10:01 UTC 2012


Chris wrote:

>After some measuring my general run of thumb is "Anything you
>leave plugged in and running 24x7 will cost you triple digits of
>dollars (at least) over a year

Well, that's a lot of "anything."  There are 8760 hours in a year, so 
a 1 kW load will consume 8760 kWH per year.  We pay about $0.08 per 
kWH here, so a 1 kW load running 24/7 costs just over $700/year (= 
$0.70 per W per year).  That puts the "three digit" point ($100/yr) 
at ~143 W.  I leave a number of LED bulbs running 24/7, which cost 
~$2.80/yr for 4 W, ~$5.60/yr for 8 W, and ~$8.40/yr for 12 W.  Even a 
new 50" flat-screen television (119 W) would only cost ~$83/yr if 
left on 24/7, and my quad-core workstation with its huge display 
would cost only ~$250.

In another post you mentioned $0.21/kWH (you must be in California?), 
so adjust all of these by a factor of 2.625 for your location -- but 
I think the service rates in most of the US are closer to ours than to yours).

Best regards,

Charles







More information about the time-nuts mailing list