- #36
microwaveguru
- 50
- 0
The concept of a microwave water heater has been around for many many years and there is a reason why it has never become commercial. It's really very simple, it is too expensive. Conventional water heaters work with immersion rods or coils that are almost 100% efficient when transferring electrical energy to heat. On the other hand, a microwave-generator and power source, such as a magnetron, is only about 50% efficient, so the electrical usage would be twice that of a conventional water heater. On top of that, the capital cost would be much higher for a microwave water heater by comparison to a simple immersion heater.
As to the heating the air with microwaves, that won't work because air, nitrogen, and other gases are totally transparent to microwave energy so there would be no heat generation. There was an interesting concept put forth by Professor Pound at Harvard, who died last year, and that was to use the microwave energy to create a “people heater”, i.e. the microwaves would heat only the people and other objects in the room and not the air. Obviously, it was never put into practice–can you imagine how terrified people would be of microwave radiation in a room? After all, many people are terrified of cell phone radiation.
As to the heating the air with microwaves, that won't work because air, nitrogen, and other gases are totally transparent to microwave energy so there would be no heat generation. There was an interesting concept put forth by Professor Pound at Harvard, who died last year, and that was to use the microwave energy to create a “people heater”, i.e. the microwaves would heat only the people and other objects in the room and not the air. Obviously, it was never put into practice–can you imagine how terrified people would be of microwave radiation in a room? After all, many people are terrified of cell phone radiation.