Date: Tue Mar 27 16:03:25 2007

Author: Paul Nord

Subject: Re: Energy

I don't think that those small LED's use much.

I've heard that the profusion of these little "wall wart"
transformers does draw a fair fraction of the home grid. I'd be
surprised if it's as much as 5%, however.

(who just replaced a 160W incandescent fixture (4 X 40W) at home with
a 60W florescent. Wow is it bright in there now! Let's see, 100W
for ~10 hours a day, ~300 days a year, ~10 cents per kWh... saves
about $30 per year in electricity. Great... now I won't feel bad
about leaving the computer on all the time. ;-)

On Mar 27, 2007, at 2:13 PM, Anthony Lapinski wrote:

> I do some of this in my classes. I take out the soft blue Indiglo
> Light
> (formerly Lime Lite). Original package stated it uses less than 2/
> year
> running continuously. Average utility rate in US is 9.5/kWh, so it
> comes
> out to about 2.5 .
> Not sure how much power the "standby" lights for TVs/stereos use,
> but they
> are on 24/7. Anyone know?
> And I obtained all the electric bills for our school, and copied one
> year's worth. I added everything up, and determined the average
> cost per
> month. My students were very surprised at how much it was! And being a
> school, it gets a much lower utility rate than "residential."
> writes:
>> Taplers,
>> Do any of you have your students estimate the energy used for
>> displays
>> like
>> continuous run CRTs, LEDs in almost every electronic device, Signs,
>> Transformers, etc?
>> Since so many of these are on 24/7 and there are so many, it seems
>> that
>> it
>> must run to a very significant amount for operating these items.
>> I would not be surprised to learn that it was near 5% of total energy
>> production.
>> Jerry H.

From Tue Mar 27 16:03:25 2007
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