Browse Groups

• ## quick numbers for electrical usage

(3)
• NextPrevious
• I calculated this for my own use, and thought it would be helpful for others. \$.14/kwh (going rate in Houston) 120 watts * 24 hours/day * 30 days/month = 8,640
Message 1 of 3 , Jul 6, 2006
View Source
I calculated this for my own use, and thought it would be helpful for
others.

\$.14/kwh (going rate in Houston)

120 watts * 24 hours/day * 30 days/month = 8,640 watt hours / month
8,640 watt hours / month = 86.4 kwh / month
86.4 kwh * \$.14/kwh = \$12 / month

So, if you have a 120V appliance/lamp/whatever that uses 120watts of power
(for instance, a light fixture with 2 60 watt bulbs), and you leave it on 24
hours a day, it'll cost you \$12 a month.

Since 120 watts at 120V is 1 amp, if you do measurements at your breaker box
(using a clamp-on amp meter, or "clampmeter"), you can see that each amp of
measurement (assuming it's for a constant, 24 hour/day load) will cost you
\$12/month.

You can extrapolate this, of course. For instance, if you have a light with
a 60 watt bulb, and you have it on for about 6 hours a day, it'll cost you
Or, if you're like me, and you have a couple of computers that you leave on
24/7, and they draw around 3 amps total, then that's costing me about
\$36/month to run them.

Paul

----------------------------------------------------------------
"All right...initialize the GBL."
"How do you do that, then?" Terry Pratchett
"It...it means pull the great big lever." from "Hogfather"
----------------------------------------------------------------
• ... You re correct, in that 6,640 watt hours would be 8.64 kwh. I had a typo in my original numbers. That should have been 86,400 watts. (120 watts * 24 hours
Message 1 of 3 , Jul 6, 2006
View Source
12:04pm, ChasMauch@... wrote:

>
> In a message dated 7/6/06 10:41:24 A.M. Central Daylight Time, tigger@...
> writes:
>
> 8,640 watt hours / month = 86.4 kwh / month
> 86.4 kwh * \$.14/kwh = \$12 / month
>
>
>
> I thought a killowatt = 1,000 watts
> so 8,640 watt hours = 8.64 kwh * \$.14 = \$1.20 month
>

You're correct, in that 6,640 watt hours would be 8.64 kwh.
I had a typo in my original numbers. That should have been 86,400 watts.
(120 watts * 24 hours * 30 days).

Paul

--------------------------------------------------------
Never trust a computer you can't repair yourself.

Paul's Corollary:
Never trust a computer that's been repaired by its user.
--------------------------------------------------------
• Don t forget about the P3 Kill-A-Watt meter. Very cool device to measure how much power something uses over time. I bought mine on Ebay last year and I love
Message 1 of 3 , Jul 7, 2006
View Source
Don't forget about the P3 Kill-A-Watt meter. Very cool device to
measure how much power something uses over time. I bought mine on
Ebay last year and I love it. They don't make one for 220 yet.

http://www.p3international.com/products/special/P4400/P4400-HG.html

Thanx

--- In hreg@yahoogroups.com, Paul Archer <tigger@...> wrote:
>
> I calculated this for my own use, and thought it would be helpful for
> others.
>
> \$.14/kwh (going rate in Houston)
>
>
> 120 watts * 24 hours/day * 30 days/month = 8,640 watt hours / month
> 8,640 watt hours / month = 86.4 kwh / month
> 86.4 kwh * \$.14/kwh = \$12 / month
>
>
>
> So, if you have a 120V appliance/lamp/whatever that uses 120watts of
power
> (for instance, a light fixture with 2 60 watt bulbs), and you leave
it on 24
> hours a day, it'll cost you \$12 a month.
>
> Since 120 watts at 120V is 1 amp, if you do measurements at your
breaker box
> (using a clamp-on amp meter, or "clampmeter"), you can see that each
amp of
> measurement (assuming it's for a constant, 24 hour/day load) will
cost you
> \$12/month.
>
> You can extrapolate this, of course. For instance, if you have a
light with
> a 60 watt bulb, and you have it on for about 6 hours a day, it'll
cost you
> Or, if you're like me, and you have a couple of computers that you
leave on
> 24/7, and they draw around 3 amps total, then that's costing me about
> \$36/month to run them.
>
>
> Paul
>
>
>
>
> ----------------------------------------------------------------
> "All right...initialize the GBL."
> "How do you do that, then?" Terry Pratchett
> "It...it means pull the great big lever." from "Hogfather"
> ----------------------------------------------------------------
>
Your message has been successfully submitted and would be delivered to recipients shortly.
• Changes have not been saved
Press OK to abandon changes or Cancel to continue editing
• Your browser is not supported
Kindly note that Groups does not support 7.0 or earlier versions of Internet Explorer. We recommend upgrading to the latest Internet Explorer, Google Chrome, or Firefox. If you are using IE 9 or later, make sure you turn off Compatibility View.