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Company Develops Microwave-powered Water Heater
dponce80 writes "Pulsar Advanced Technologies has announced that, starting next week, they will launch the MK4, a microwave-powered on-demand water heater. Why is this cool? Well, until now, you had two options: electric heaters that keep a large amount of water hot at all times, or natural gas heaters that heat up water on-demand. The first is very costly and wasteful, and the second is not available to everyone, especially those in rural areas. You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity. Not so with microwaves. The Vulcanus MK4 can heat water from 35 degrees Fahrenheit to 140 degrees Fahrenheit in seconds and can source multiple applications at once: showers, dishwasher, sink usages and more. The Globe and Mail has an article with a little more information."
I'M a conventional resistance-based electric element, you insensitive clod!
BTW, the article 'summary' contains wholesale copy/pasting from the article linked to, which itself is just a press release that offers no additional data.
Has anyone considered putting together a submission etiquette guide for the editors to use when greenlighting stuff? Something that includes a dupe check, a Ron P. filter, and perhaps a 'marketfluff' detector? Such a device would come in handy for things like this, "articles" that make Popular Science read like the freakin' Encyclopedia Brittanica in comparison.
This reeks of some marketing crap. There are plenty of on-demand electric heaters with very high flow rates. Yes they require massive amounts of electricity, but I don't know that a microwave based unit would require that much less. Since they don't quote any power rates or even seem to acknowledge their competition's existing and time tested products it leads me to believe that this is a bunch of marketing hoopla to drum up business for their products.
If you want to heat 2-3 gallons of water per minute from say 50F to 130F using electricity you need a SERIOUS load. These on demand electric heaters often require 100 or 200 amp breakers BY THEMSELVES which most often means that in order to use them you have to upgrade your home's entire main breaker panel AND you may have to pay the utility company to give you this type of service as they typically do not have not installed equipment and lines capable of providing this amount of power to a home.
I do se a bit of an advantage in that it's possible that an on demand microwave heater, although ideally less efficient than ceramic/resistance based heaters, could provide both a size and a maintenance advantage over a conventional heater.
On-demand water heaters have been around a very long time and it seems in the last year or two they have come back in vogue again. They work OK. They can save you money. But most people can also save money with a much less substantial outlay by upgrading their old water heater to a newer model that is better insulated and more thermal efficient. There are even dual gas/electric heaters that let you change fuels to suit whatever is currently cheaper. In many areas such as the one I live in electricity is much less expensive in the winter than in the summer and gas is the opposite.
I think the point was not that immersion heaters are inefficient in that way (i.e. in the true physical sense), but that because they cannot heat water quickly, they have to keep a large amount of water hot at all times in case it is needed. This is inefficient (not in physical sense) because the vast majority of the heat that is transferred to the water is lost to the atmosphere while the water sits around waiting to be used. Gas heaters, however, can heat water quickly (on demand), and thus no energy is being used to heat the water until it is required.
Actually, you are wrong.
You forgot about 2 elements to the story.
1. EXCEPT for cold Northern climates where the heater is properly installed inside the house's heated area (not all of them are, some are in closets in the garage) all the heat used the majority of the time is wasted for a typical heater. Have you ever noticed how much that thing is running during the day when there is minimal demand for hot water? Net efficiency can't possibly be above 50%.
Oh, and you still pay a lot more for the 'heat' wasted by the electric hot water heater than you do for heat generated by the fuel burning furnace (whether it uses oil or natural gas). A system that doesn't have that waste heat would be more economical.
2. Where do you think the energy lost in capictors, magnetron, ect goes? I have a bright idea...let's put the heat sinks for those AGAINST THE WATER TANK COLD SIDE!!! DOH! Where else do you think the heat for a 2000 watt magnetron gets dissipated. Without knowing exactly how this implementation of a fairly obvious idea actually works, I can say that that would take some bigass fans and a huge radiator to get rid of 40% of the heat lost running a magetron this big. It must be a BIG one to heat water in these volumes this fast. It almost certainly MUST vent the excess heat into the cold water coming into the system through a radiator or something. This would have the net effect over a prolonged run-time (perhaps someone is taking a shower) of making the system very efficient. Perhaps 90% net.
At the least, this kind of system should obsolete electric hot water heaters, as well as electric assists to solar and geothermal systems.