> Switch to compact fluorescents. A 26W one should provide as much light
> as a 100W one.

LEDs are the way forward, they are more efficient (and getting more 
efficient the whole time) and more environmentally friendly (they don't 
contain mercury) and fix almost all of the disadvantages CFLs have.  Just 
wait...

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>> Switch to compact fluorescents. A 26W one should provide as much light
>> as a 100W one.
> 
> LEDs are the way forward, they are more efficient (and getting more 
> efficient the whole time) and more environmentally friendly (they don't 
> contain mercury) and fix almost all of the disadvantages CFLs have.  
> Just wait...

I don't know about CFLs, but our house has several "energy saving" 
lighting units. The problem is, there's a 20 minute delay between 
turning them on and being able to see where you're going...

LEDs are indeed efficient, but the main problems currently seem to be 
making "white" light with them, and illuminating large areas.

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andrel wrote:

> Are you cooking electric? How do you heat your house?

Both of those are gas.

The microwave oven, however, is electronic. I haven't measured it, but 
it's rated at 900W. (I have no idea whether that means it uses 900W of 
juice, or just that it produces 900W of microwave energy.)

> Anyway, there is this problem that your PC may be on for periods much 
> longer that the washing machine.

Like I said, playing CSS (which you're presume is a reasonably intensive 
task) for 2 hours solid used a fraction of one kWh. I don't know what it 
uses if I run the computer for an entire day (presumably it varies by 
the task I set it to do), but I imagine running the washing machine 
several times per day - or accidentally leaving the lights on - uses far 
more power.

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> I don't know about CFLs, but our house has several "energy saving" 
> lighting units. The problem is, there's a 20 minute delay between turning 
> them on and being able to see where you're going...

Yup, and not having studied them carefully, I hear they make a slight 
buzzing noise which can be annoying in a quiet room (eg while trying to 
read).

> LEDs are indeed efficient, but the main problems currently seem to be 
> making "white" light with them,

There's no problem with making white light, the most efficient way is just 
to put a mixture of different coloured LEDs in one "lamp" to give whatever 
white temperature you want.  The other way is to put a yellow phosphor 
infront of a blue LED, but that's not as efficient electrically (it means 
you can get white from a single LED though).

> and illuminating large areas.

The biggest problem is keeping the LED temperature low enough during use, 
the designs I've seen have been mainly heat sink, but they seem to have 
overcome that for 60W and 100W equivalent bulbs:

http://www.metaefficient.com/leds/led-light-bulbs.html

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scott wrote:
>> I don't know about CFLs, but our house has several "energy saving" 
>> lighting units. The problem is, there's a 20 minute delay between 
>> turning them on and being able to see where you're going...
> 
> Yup, and not having studied them carefully, I hear they make a slight 
> buzzing noise which can be annoying in a quiet room (eg while trying to 
> read).

I haven't found that to be a problem yet.

The main problem for me is that they're just not bright enough. I 
actually can't tell what colour my clothes are in the morning because I 
don't have 20 minutes to stand there waiting for the thing to get bright.

>> LEDs are indeed efficient, but the main problems currently seem to be 
>> making "white" light with them,
> 
> There's no problem with making white light, the most efficient way is 
> just to put a mixture of different coloured LEDs in one "lamp" to give 
> whatever white temperature you want.  The other way is to put a yellow 
> phosphor infront of a blue LED, but that's not as efficient electrically 
> (it means you can get white from a single LED though).

OK, I rephrase: I personally have yet to see a "white" LED that wasn't 
actually pale blue.

>> and illuminating large areas.
> 
> The biggest problem is keeping the LED temperature low enough during 
> use, the designs I've seen have been mainly heat sink, but they seem to 
> have overcome that for 60W and 100W equivalent bulbs:
> 
> http://www.metaefficient.com/leds/led-light-bulbs.html

Well, I'm sure the technology won't stand still. IIRC, my dad has some 
small LED ligth fittings illuminating the stairs. But they're not very 
bright. (Despite containing about a dozen LEDs each.)

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> OK, I rephrase: I personally have yet to see a "white" LED that wasn't 
> actually pale blue.

That's because you're used to "normal" light bulbs that are very very yellow 
(just try taking a photo indoors with the camera on "outdoor" setting and 
you'll see what I mean).  It's not that LED manufacturers can't make this 
colour, it's just there is no demand for it (backlights for LCDs need a much 
bluer white than normal light bulbs).  If you want to make a yellower colour 
yourself then you can make your own yellow phosphor to put on a blue LED, or 
just place some yellow LEDs around the white ones :-)

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scott wrote:
>> OK, I rephrase: I personally have yet to see a "white" LED that wasn't 
>> actually pale blue.
> 
> That's because you're used to "normal" light bulbs that are very very 
> yellow.

How about sunlight? Is that yellow too? (I mean, by the time it reaches 
the ground.)

> It's not that LED manufacturers 
> can't make this colour, it's just there is no demand for it (backlights 
> for LCDs need a much bluer white than normal light bulbs).  If you want 
> to make a yellower colour yourself then you can make your own yellow 
> phosphor to put on a blue LED, or just place some yellow LEDs around the 
> white ones :-)

Heh. The trouble is the light in my room ("energy saving bulb") gives 
off such a pinky yellowy colour that I can't actually tell whether an 
item of clothing is blue or black. :-P

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> How about sunlight? Is that yellow too? (I mean, by the time it reaches 
> the ground.)

It's really difficult to say, as everything to do with "white" is relative 
and your brain does a really good job of filtering out changes in white 
balance of your environment.

Here's a chart I found detailing the sunlight spectrum:

http://org.ntnu.no/solarcells/pics/chap2/Solar_Spectrum.png

You tell me if that's "yellow" or not :-)

> Heh. The trouble is the light in my room ("energy saving bulb") gives off 
> such a pinky yellowy colour that I can't actually tell whether an item of 
> clothing is blue or black. :-P

That's not so much to do with the absolute colour of the white light, but 
with the spectrum.  If you have two monochromatic light sources from a 
yellowy-red laser and a blue laser you can make white light.  THe problem is 
when you try to illuminate something with that white light, the only thing 
you will see is how well the object reflects those particular two laser 
wavelengths.  On the other hand, white light from a black body gives you a 
much better impression of the "colour" of an object because it consists of 
visible light from all wavelengths.  There's a thing called "colour 
rendering index" (CRI) that describes this quality of white light.

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"Saul Luizaga" <sau### [at] netscapenet> wrote in message
news:49b40bc4$1@news.povray.org...
> http://www.worldcommunitygrid.org/about_us/viewAboutUs.do
>
> http://www.one.org/
>
> If you have any spare core(s)/CPU(s) please help to help, is for
> Humanity sake, thank you.

"Humanity's sake" is all nice and good, but if these grid projects are to
achive better success, they should consider some minimal payment, to
compensate for energy usage at least. Nothing is free, and in the end, that
anti cancer drug you help discover (albeit in an extremely minor way) will
be sold to you at hundereds or thousands of dollars a pop if and when you
need it. An alternative is to make such research and end products public
domain and patent free.

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If the concern is really over electricity usage, consider that a supercomputer
center is always climate controlled, year-round. Whereas leaving my home
computer powered on (with monitor off) 24hrs a day is helping reduce my usage
of propane to heat my home during the winter months. All while helping
scientists learn how they will cure me of cancer when I reach that stage in
life.

To build a supercomputer center requires many years, and committees, and who
decides what runs on it? And who will fund the construction? Who funds the
ongoing operations? What does the machine do when it would otherwise be idle?
Sometimes all the bureaucracy that surrounds such projects gets in the way of
good fundamental science.

Learn more about Rosetta@home. Helping do the research with my home computer is
something that can be done today. No need for a government approval or
committee meeting. I've got it running right now, in the idle time between
keystrokes. The cost of the power used by a computer is minimal compared to the
cost of trying to treat someone with cancer using today's methods. Think of it
as an insurance policy. Or a savings plan with compound interest.

http://www.youtube.com/watch?v=GzATbET3g54
http://boinc.bakerlab.org/rosetta

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