An air-heater based on nitrogen-absorption of EMR -- practical?

[Green Xenon]

Hi:

 

I'm thinking of a theoretical device that could be used as an air heater for the home. This device emits a wavelength of EM radiation that is best absorbed by nitrogen. This causes the N2 molecules to heat up. Since the air on earth's atmosphere consists largely of nitrogen, could such a device be used to keep a house warm during winter?

 

As air is pumped into the house from outside, it passes through this device, absorbs the radiation and gets warm. Finally, the air enter the rooms through the vents.

 

The advantage I see to such a device is that it wouldn't cause the house to have the classic "heater" smell.

 

What would be the disadvantages -- excluding cost -- of such a device? Could anyone suggest something better?

 

 

Thanks,

 

Green

[CaptainPanic]

1. What is the effect on the nitrogen of the absorption? Will it just "heat up" the air? Will it ionize the nitrogen? Will the nitrogen emit light?

Note that ionized air, which possibly can react (and for example form NOx) will have a smell far worse than the "classic heater" smell.

 

2. What is the absorption coefficient? (In other words: how many meters if nitrogen do you need to absorb your beam?) How likely is it that you have enough space in a house?

 

3. Can the radiation be absorbed by other materials (especially common things like the human body, plastics, wood, concrete, etc)? Will all other materials be reflective to it (quite unlikely)?

 

4. Your idea uses electricity, which is relatively expensive.

 

I would suggest a standard CV installation. The radiators are below 100 deg C, and cause no smell. It's a system that can possibly run on industrial waste heat, which is an ecologic benefit.

[Green Xenon]

I would suggest a standard CV installation. The radiators are below 100 deg C, and cause no smell. It's a system that can possibly run on industrial waste heat, which is an ecologic benefit.

 

What does "CV" stand for?

[CaptainPanic]

What does "CV" stand for?

Oops

That's a dutch abbreviation (silly me). It stands for central heating, often with water circulation to radiators.

 

Apologies for the confusion.

[John Cuthber]

It is, what is technically called "bloody difficult" to get a lot of radiation that's absorbed by nitrogen.

It has no IR absorption spectrum and no microwave absorption spectrum.

It doesn't absorb in the near IR, the visible or the near UV. In fact it only starts to absorb in the UV at very short wavelengths. At those wavelengths oxygen does a much better job of absorbing the radiation and is converted reasonably efficiently into ozone which is poisonous.

 

There might be some selective absorptions somewhere in the Xray region of the EM spectrum but who cares?

Monochromatic Xrays are so hard to make that you could use the waste heat from your X-ray generator to heat several thousand other buildings.

[Green Xenon]

It is, what is technically called "bloody difficult" to get a lot of radiation that's absorbed by nitrogen.

It has no IR absorption spectrum and no microwave absorption spectrum.

It doesn't absorb in the near IR, the visible or the near UV. In fact it only starts to absorb in the UV at very short wavelengths. At those wavelengths oxygen does a much better job of absorbing the radiation and is converted reasonably efficiently into ozone which is poisonous.

 

There might be some selective absorptions somewhere in the Xray region of the EM spectrum but who cares?

Monochromatic Xrays are so hard to make that you could use the waste heat from your X-ray generator to heat several thousand other buildings.

 

 

Just out of curiosity, lets say there is a hypothetical environment in which the only gas is nitrogen. What will be the non-thermal effects if EM radiation [at a frequency best absorbed by nitrogen but least absorbed by entities other than nitrogen] is emitted into that environment? Since the only gas is nitrogen, there is no chance of producing NOx, ozone or other toxic compounds.