I once cooked a hotdog on a melamine (hard plastic) plate in a microwave. Once. When my 'dog was done I picked that plate up, set it right back down again, and had un-complimentary things to say. That set me thinking. Instead of using resistance coils (the most inefficient way of producing heat), or fossil fuels for home heating, why not do away with gargantuan central systems & mount shoebox-sized mini-units at each register? Melamine reacts very well to microwave radiation, so why not build a honeycomb of it? Shoot a little micro, use a small fan to blow air thru the comb, and, voila! What's even better, as heat's being produced right at the vent, certain rooms can be programmed, via a simple computer chip, to maintain pre-set temperatures during the day or night. Even if someone still insisted on central heat, a bigger gizmo could replace the old, inefficient set-up.
-- quibix, Jun 20 2005

I think it'd be horridly inefficient. No, I can't articulate why. Just a hunch.
-- bristolz, Jun 21 2005


Any system that uses electricity for local ambient heating can never be inefficient compared to another electrical system, since inefficiencies in an electrical system product heat. You didn't explain why resistance coils are inefficient. Is it because they eventually wear out and need to be replaced? There doesn't seem to be any advantage over a traditional fan heater, which would be cheaper and easier to service.

Perhaps there could be another application for this phenomenon, such as improving efficiency of waste treatment using catalytic converters.
-- oldchina, Jun 21 2005


Well, I happened to read once, in a trade publication, that electrical resistance is the most inefficient way of producing heat. And, I know, from personal experience, that a tiny melamine saucer gets hotter than all get-out from just a minute's worth of microwave radiation. I ran this idea by someone else, who said mineral oil is even more receptive to microwave bombardment. So, even if solid melamine isn't the material of choice, a synthetic heat exchanger filled with mineral oil should do it.
-- quibix, Jun 22 2005


What me [oldchina] said, except possibly the part about waste treatment. Not my forte.

I think [quibix] may be confusing efficiency with cost effectiveness. In terms of cost effectiveness, the microwave/melamine idea gets a bone.
-- Texticle, Jun 22 2005


Electricity in general is less efficient for heating than directly burning fuel because of the losses incurred during generation and transmission. That's one reason why electrical heating usually costs much more.

The microwave oven is not going to magically produce more energy than a resistance coil. Any electrical energy you put in is going to come out as heat, unless you're running a radio transmitter or light house. You'll use the same number of kilowatt-hours to make your house toasty. It doesn't matter how you transfer that energy from the electricity to the air.
-- oldchina, Jun 22 2005


Quibix,

I had the same thought and, in fact, found this site because of your idea. (Search for "Microwave home heater" in google) I think I've figured out the best way to describe why it's not more efficient.

In the Microwave there is no heating element. Your food is the hottest thing in the oven because it is radiated directly. What if Microwaves worked by radiating a melamine coil that then heated your food? That doesn't sound as efficient as directly radiating the food. I think if you could get some smart microwaves that gently radiated the people in the home... I've heard that resistance coils are actually really efficient heat producers. I can't imagine electrical resistance is the most inefficient way to produce heat. I've been wrong before and will be wrong again. Good luck. Mr. Mike
-- MrMike, Nov 14 2005


I think that microwaves could be better than resistance heaters, but not in an instant heater configuration. I`ll explain...Take an oil filled heater for example. It accumulates heat and this heat is used over a period of time. The more oil you have, the longer the heat can be used. To be able to get the oil hot, a heater is used. This heater is said to be extremely efficient because it is surrounded by oil, therefore no losses of energy to the surroundings. Now, we know that microwaves can penetrate substances and heat different layer at the same time. Would it make sense to say that the oil in an oil-filled heater would be heated in less time if we used microwaves instead of using a conventional heating element? I had myself an idea similar to Quibix, but using ferrite or graphite rods, which are more susceptible to microwave radiation. Similarly, a ferrofluid could be used as a substitute to mineral oil when it comes to oil-filled heaters if microwaves would be the source of energy. Any input would be great.
-- spacifique1, Aug 01 2006



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