One bad side about infrared, as far as it being a heating device, is that the IR rays do not travel that far. Often the distance is not enough so the need for multiple devices in a room may be needed.
Infrared Heaters (http://infraredheaterwarehouse.com)
I know what you mean and I agree with you but it's very misleading to put it the way you do.
Infrared "rays", like all electromagnetic radiation, have essentially infinite range. They travel until they interact with something, which may be all the way across the visible Universe.
They spread out, too, and that's why there's that inverse-square falloff with distance. So, yes, if you are twice as far from your IR heater you will be getting 1/4 the illumination -- that is, 1/4 the warmth -- from it. And since the air is transparent to the IR, the air isn't warmed by it, only the surfaces that "see" the IR are warmed by it.
IR radiant heaters are good for spot heating of persons, right up close. They are not good for heating volumes of air.
All the input power to the heater eventually ends up heating the environment. But which parts of the environment do you want to heat up first?
Halogen type infra-red heaters are very efficient compared to hot air blower heaters. They provide instant localized heating on the person just 1kw or less is often enough to feel very warm. An electric hot air blower on the other hand must heat all the volume of air passing though it which often takes 3Kw to feel the same heating effect at the same distance away from the heaters. Of course they both heat up the room eventually but its a waste of energy to do this unnecessarily especially where one is trying to save money.
If you want or need to heat up the entire room using electric then use Heat pumps or Air Con units which provide 3-4kw of heating for 1kw energy input. This is an OU device COP>3 :)
Infrared light isn't really "transparent" in air. Greenhouse gases absorb infrared light. This effect results in vibration of greenhouse gas molecules in the presence of the infrared radiations. As the greenhouse gas molecules vibrate, dipole moments are formed and warm up the space which the greenhouse gases occupy.
Your right, most impurities in air add to the effect,
but have you ever asked why air doesn't do this ?
You can run an infrared heater in a large space with
"nothing to heat" and the results will be abismal.
Again, I agree, with the exception of heat pumps,
infrared makes "People" feel the most comfortable.
Infrared on plain air plains sucks
Quote from: bolt on January 14, 2011, 07:49:26 AM
Halogen type infra-red heaters are very efficient compared to hot air blower heaters. They provide instant localized heating on the person just 1kw or less is often enough to feel very warm. An electric hot air blower on the other hand must heat all the volume of air passing though it which often takes 3Kw to feel the same heating effect at the same distance away from the heaters. Of course they both heat up the room eventually but its a waste of energy to do this unnecessarily especially where one is trying to save money.
If you want or need to heat up the entire room using electric then use Heat pumps or Air Con units which provide 3-4kw of heating for 1kw energy input. This is an OU device COP>3 :)
bolt
thats funny you mention this ...
as i was yesterday working on a unit that does this ... smaller scale .. i was trying to acheive overunity operation ..
but the way i left the unit was like this .. 10w haligon a 12 volt fan .. running along time on a small 12v battery
both operating on high frequency electricty .. a motor and a light and i was recovering to a boost cap to close the loop
insted .. ill build a heater ..
can i call it the bolt? i made a lot of videos of it .. and demonstrating the effects .. witch are verry kool...
as i hooked up the cap the long spikes dissapear i hook up the light and the motor the medium spikes dissapear
and im left with a nice wave witch is the pulseing curcit it is verry efficient but NOT OVERUNITY.. darn close .. if i added up all the work and the recovered energy it is ou .. but .. it aint good enough yet
the recovered energy is to be pumped back into the source via ferroite transformer cap charger running low volt high freq the concept is sound and i have prototyped all angles ..
ill keep at it .. i post this hear as it is IF and gets darn hot from 10 watts ...
william
:)
Quote from: CompuTutor on January 14, 2011, 11:43:50 PM
You can run an infrared heater in a large space with
"nothing to heat" and the results will be abismal.
In a large open space, the infrared radiations will be subjected to dispersion loss if the air does not contain enough greenhouse molecules that retain the heat.
However, if the space is foggy, or if the space is crowded with many people, the ordinary infrared heater will work. Water vapors, carbon dioxide and methane (from flatulence) are greenhouse gases.
Perhaps, this is the reason why a few railway stations in the UK are noticeably warmer than the others.
Not all the infrared lights are good. Some infrared lights hurt our eyes. The far-infrared lights from the sun have healing effects that benefit people with arthritis and/or heart diseases. Some materials on earth can generate a trace amount of far-infrared lights not very much different from those from the sun.