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."

Jeepers

[Chairboy]

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.

microwaves more than 100% efficient?

[joostje]

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.
So, microwaves need less energy to heat up water the same amount? Strange... The heating with resistance-based methods is already close to 100%; the loss occurs with storage of the warm water. But you do need the same amount of energy (and thus electricity) to heat up water, whether you do it using resistance-based methods, or microwaves.

Marketing Crapola!

[GoRK]

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.

Re:bad science = scam

[Lynx0]

OK, I'll buy the first part, you can't heat water quickly enough for on-demand use such as a shower, as it would require unreasonably high current, even if the electric water heater was 100% efficent. I've done the math on that.

You must be really bad at math, because I had a shower one hour ago using the on demand electrical heater that's been in my apartment for some 15 years. And it was set to "1", because the water is too hot to shower with on the "2" setting.

I am extremely dubious of these claims

[Andrew Price]

I recently researched buying an electric on-demand water heater for my own home. Such heaters consume around 10-20kW and can demand 100 amps of current, they are however very efficient (as someone else noted) and so there is little waste to squeeze out of the system (a few percent at most I expect). Using microwave generating magnetrons is likely to be less efficient imo, so it is very hard to see how this company can live up to its claims. Whether by microwave or resistive heating, the same amount of energy needs to get into the water, it is not at all like a food stove where microwave ovens are genuinely more efficient (less heat loss and only the item being cooked is heated, not the stove walls too). The reason I didn't purchase an on-demand heater is that the electric service in my house would have to be upgraded, at a cost of around $3000. A new water tank, with heater, cost $700. The microwave heater would also have this cost issue. A better way to save power (nationally) would be to have dual-band power pricing (as is done in the UK) where power used in off peak hours costs less than in peak hours -- in this case a storage tank is potentially MORE efficient than on-demand since it can shift demand to off-peak hours when there is unused capacity. In any event, I doubt that a properly insulated water tank actually loses much heat, the main advantage of on-demand is that there is a never-ending supply of hot water. Andy

Re:microwaves more than 100% efficient?

[devilspgd]

Okay, stupid question time.

Prerequisite: I live in an area of the planet where I am heating, rather then cooling my house the majority of the year. None of this applies to anyone with an air conditioner turned on right now.

I currently heat both my house and my hot water with natural gas. Any heat that my hot water system (tank, pipes, etc inclusive) releases into the environment isn't really lost -- The "environment" into which the heat is being released is also known as my house.

The only "lost" heat is that which is carried by water out the drain and into the city's waste system.

Every bit of heat that is lost due to the inefficiency of storing the water is an equal amount of heat gained by my house, and the result is that my furnace uses that much less energy to keep my house at a comfortable 20C.

Now in my current house I'm actually using a boiler rather then a furnace. Assuming both my boiler and my hot water tank are equally efficient (which is likely fair, since both appliances do the same job, they heat water), and since they use the same energy source and hence neither is more economical, I don't think I'm losing anything by using a hot water tank rather then an on-demand method, am I?

Re:that's more like it

[hjsb]

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.

Don't forget, 110V vs 230V

[Anonymous Coward]

Some of the arguments here as to if you can/cannot do 'on-demand electric water heating' due to the power requirements are probably because people aren't taking into account 110V vs 230V countries.
The wiring in a house on the 110V system might not be able to handle the current but the wiring in a house on the 230V system definitely can.

Re:that's more like it

[ShooterNeo]

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.

Crapola, or payola?

[Tau Zero]

There are three possibilities here (see journal for details):

1. CowboyNeal is a science-illiterate and has no concept of conservation of energy (and should not be editting science stories).
2. CowboyNeal is just stupid (ditto).
3. CowboyNeal is taking payments to promote fraudulent products (and should be fired).

I can't think of any other possibilities here.

Re:that's more like it

[dusty123]

The simple reason for hotter water after flushing the toilet is the following:

When taking _cold_ water from your system, such as for your toilet, there is an overall lower water pressure in the system. Therefore less cold water flows through your heater. Less water can be heated to higher temperatures, therefore the hot water is hotter until the toilet is filled with water.

Re:that's more like it

[dk.r*nger]

(We'll ignore the heat from the water which radiates through the heater; the energy loss from the hot water will occur with both conventional and microwave heaters.)

That's not a very good idea.

The radiation heat from a waterheater is very much significant. It is minimal in the mentioned setup because the water is not heated before it is needed. It may be much less efficient watt-by-watt if you use a lot of hot water around the clock - but in a typical residential setting where you only need hot water a few times a day - but need it immediately - the microwave solution could prove to be very efficient.
If you go heat up the exact amount of water you need, right when you need it, and is prepared to wait a bit for it, the electrical solution is likely the more efficent.

Re:that's more like it

[Anonymous Coward]

Gas doesn't count because it's already mentioned in the summary, which indicates that the microwave heater would be a good alternative where gas is not available.

Re:that's more like it

[ray-auch]

Where is this that has such stone-age on-demand heaters?

places without gas supply (see article summary)

Gas on-demand heaters have been able to cope with a pretty good range of flow rates for years.

as article summary also says. this is supposed to be an improved _electrical_ option for places that don't have gas.

Re:that's more like it

[mpe]

Here in East Texas we run the AC 7-8 months a year. We, typically, have the hot water heater in the garage so as not to run up the AC bill. What makes the most sense, here, is a solar hot water system.

How about having your AC heat up the water?

Ever pay a plummer

[goombah99]

Plummers make a lot of money for not much work. sounds like he's a smart guy.

Re:Electric resistance-based quite common

[tcgroat]

Another advantage to tankless heaters is that they can be located closer to the point-of-use than a large central heater. With a central heater, the water must flow for some time to flush the cold water out of the pipes between the tank and the shower or sink, and warm up the pipes so the water isn't cooled on the way. Several gallons are wasted before hot water reaches a tap at the far end of the plumbing.

Re:that's more like it

[Anonymous Coward]

He had courses in Thermodynamics, chemistry and electrical engineering, not degrees. Could be that he's a student and is just doing it to pay his way through college, or even never finished and decided that he'd be happier doing plumbing (sense of satisfaction in physically completing jobs, change in scenery installing in different places, very respectable pay...) Besides, the post said nothing about installing them professionaly, just that he's installed dozens. Could be that he's a very helpful guy and is doing it for neighbors, family and/or friends?

Looking through your posting history, you seem to be generally on topic and insightful, so I'll just blame this one on a turkey hangover.