 |
|
|
|
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On Sat, 01 Sep 2007 19:11:57 +0100, Orchid XP v3 wrote:
> I haven't tested out the TV yet, but of all the stuff I have tested, it
> seems that any device that performs any kind of *heating* instantly uses
> many times more power than anything else. I emphasize: MANY TIMES more
> power. Not 20% more, not 50% more, but nearer to 1000% more! Heck, even
> the vacuum cleaner (surely a high power device) in fact uses a fraction
> of the power that the toaster does!
>
> Can anybody suggest why this might be? I mean, huge powerful electric
> motors use a fair bit of power, but it's almost insignificant compared
> to heating devices. Why does heating things require so much power?
Heat is generated through increased electrical resistance; in order to
heat a heating element up, you need to push more electricity through it.
http://en.wikipedia.org/wiki/Heating_element is a good starting point.
Jim
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
I think they are starting to use microwaves in
indirect heating in some high end ovens. The
microwaves heat some sort of target element,
then pump air thru it, the oven door can be
opened without fear of microwave leakage.
It reduces cooking time, but I bet it's better
in terms of power usage too.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Tim Attwood wrote:
> I think they are starting to use microwaves in
> indirect heating in some high end ovens. The
> microwaves heat some sort of target element,
> then pump air thru it, the oven door can be
> opened without fear of microwave leakage.
> It reduces cooking time, but I bet it's better
> in terms of power usage too.
There are also induction cookers which are significantly more efficient
than traditional conduction cooktops.
http://en.wikipedia.org/wiki/Induction_cooktop
Lance.
thezone - thezone.firewave.com.au
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Orchid XP v3 wrote:
> Can anybody suggest why this might be?
It's because heat represents a huge amount of energy.
For instance, the humble calorie, the amount of energy required to raise
a single gram of water by one degree celsius, is the same amount of
energy required to lift that same gram of water about 387 meters in
Earth's gravity, or accelerate it from zero to 87 meters per second.
Regards,
John
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Orchid XP v3 wrote:
> PS. We have *another* Intel Core 2 Duo laptop at work. And just like the
> first one, it seems to be utterly impossible to make it heat up, no
> matter how much number chrunching I throw at it. How do they manage that?
I have a 2Gig Celeron laptop (from 2003) that gets very hot when it has
to crunch, like during a POV-Ray render.
Regards,
John
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On Sat, 01 Sep 2007 18:19:25 -0700, Tim Attwood wrote:
> I think they are starting to use microwaves in indirect heating in some
> high end ovens. The microwaves heat some sort of target element, then
> pump air thru it, the oven door can be opened without fear of microwave
> leakage. It reduces cooking time, but I bet it's better in terms of
> power usage too.
Probably, but I'm always reminded of the phrase "there ain't no such
thing as a free lunch" - when it comes to generating heat, physics still
applies. Doesn't mean things can't be more efficient than they currently
are, though.
Jim
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Thibaut Jonckheere wrote:
> No answer (sorry), but two questions :
>
> - What device do you use to mesure power ? Is it expensive ?
I said it in my blog, and I'll say it again here:
http://www.maplin.co.uk/search.aspx?menuno=80119&MenuName=Power%20and%20Energy%20Monitors&FromMenu=y&worldid=-6&doy=28m8
> - Have you tried to mesure the power used by electronic devices (TV,
> HiFi, etc.) when they are on standby ? I find it difficult to get a
> estimation for this, and it seems to vary greatly even among similar
> devices ?
Some devices actually use 0 W when off. (A few use 0 W even when on. For
example, the clothes iron, once it's hot.) Most things seem to use less
than 5 W while on standby.
And yes, the TV is one thing I still haven't got round to measuring!
--
http://blog.orphi.me.uk/
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
>> Can anybody suggest why this might be?
>
> It's because heat represents a huge amount of energy.
>
> For instance, the humble calorie, the amount of energy required to raise
> a single gram of water by one degree celsius, is the same amount of
> energy required to lift that same gram of water about 387 meters in
> Earth's gravity, or accelerate it from zero to 87 meters per second.
Damn... pitty we can't use heat to do *useful* stuff!
--
http://blog.orphi.me.uk/
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
46daa206@news.povray.org...
>
> Damn... pitty we can't use heat to do *useful* stuff!
>
Watt?
Marc
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
> Probably, but I'm always reminded of the phrase "there ain't no such
> thing as a free lunch" - when it comes to generating heat, physics still
> applies. Doesn't mean things can't be more efficient than they currently
> are, though.
Problem with conventional cookers is they tend to heat up your kitchen
too...
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
