They have a magnetic component as well as an electrical component. Where things begin to unravel is the condition where people forget that the conversion of electricity into RF is never 100% efficient, and the ability for RF to do actual work with a conductor is never 100% efficient. Thus, there are two stages of energy loss (expense) in addition to the amount of energy it takes to dissociate water by simply putting electrodes and DC into the water. And even simple electrolysis is a losing proposition in supplying hydrogen as "Fuel", starting with the fuel to generate the electricity and the associated inefficiencies, transmission losses, etc.
The only reason a microwave oven is faster in cooking is because a wavelength is chosen that resonates with the water dipole. It is not particularly more energy efficient than a hot plate, with a 100% efficient heating element. It just gets the energy in faster.
Thermodynamics reduces to "There is no free lunch". It's "slow and cheap" or "fast and expensive". a 700 Watt microwave, or a 200 Watt hot plate-Both do the job.
Guys,
I am not saying that it does not take electricity to create the RF waves or that this is a free energy lunch. What I was saying was that this is a very interesting discovery. And, yes, it is a discovery because no one has ever done this with radio waves before. The “discovery” is that you could use RF to achieve the result and that this was not something that we all learned in junior high school. Whether it translates into a wonderful new enegy source was not the point of my posts. The point was how quick some members of FR are to jump all over anything like this. It happens quite a bit and I find it to be a bit cynical in that you can’t just appreciate the joy of the discovery. Some would rather find the “bad” and, at the same time, show everyone just how smart they are.
This may not have been the intention of anyone today but that is the way it comes across.
Smallest hotplate I’ve ever seen is 1500 watts. You use it to heat the container, which in turn heats the water. Microwave puts most of the heat directly into the water. That makes it more efficient twice. (not two times as efficient, but two modes of efficiency.)
Actually, it doesn't resonate the water molecules; it just heats them (and the lipids proteins, etc.) by frictional motion.
The reason for its speed is that it delivers the energy to the interior of the food, whereas radiant/convection ovens have access directly only to the surface, and penetration to the interior takes more time.
The reason for its energy efficiency is that little or none of the energy goes into heating the enclosure or the food container (assuming you're following directions!).
Thermodynamics reduces to "There is no free lunch". It's "slow and cheap" or "fast and expensive". a 700 Watt microwave, or a 200 Watt hot plate-Both do the job.
The formulation I heard years ago in school still amuses me.
1. You can't win.
2. You can't break even.
3. You have to play the game.