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Company Develops Microwave-powered Water Heater

CowboyNeal posted more than 8 years ago | from the pacemakers-beware dept.

Technology 505

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."

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ooooh (5, Funny)

tonywong (96839) | more than 8 years ago | (#14111593)

Another fine product from Wayne Enterprises Military Division...

that's more like it (2, Funny)

theshowmecanuck (703852) | more than 8 years ago | (#14111595)

Now I can have a long hot shower in 30 seconds.

Kill germs too? (2, Interesting)

jimmyhat3939 (931746) | more than 8 years ago | (#14111596)

Microwaves kill various germs too, don't they? They should market this as both a water heater and a sanitizer.

Re:Kill germs too? (0)

Anonymous Coward | more than 8 years ago | (#14111670)

Microwaves (the frequency which heat water) are only absorbed by water.. If any germs die it's because you're heating the water up enough to denature them, which you would do if you heated up the water by any other means.

Re:Kill germs too? (1)

Broken_Ladder (821456) | more than 8 years ago | (#14111762)

no. wrong. microwave ovens use frequencies that are specifically "tuned" to the water molecule. this doesn't mean they don't still excite other molecules.

put a glass in the microwave some time, or a piece of plastic. it will get hot.

Re:Kill germs too? (1)

Leroy_Brown242 (683141) | more than 8 years ago | (#14111679)

That is the very first thing that came to mind.

2 birds with one radiation treatment, or something.

Re:Kill germs too? (3, Funny)

Kadin2048 (468275) | more than 8 years ago | (#14111687)

Just think if they heated the water using a critical-sized lump of plutonium -- then it would both heat and irradiate your water! For maximum germ killing power. And it wouldn't just be 'on demand' hot water, it would be hot water all the time whether you want it or not.

Plus it would be emission free, and a great use of all those Soviet ICBM warhead initiators that are just sitting around, going to waste.

Just don't turn off the cold water supply....ever.

Re:Kill germs too? (2, Funny)

Supurcell (834022) | more than 8 years ago | (#14111811)

I'm sure in 1985, plutonium is available at every corner drugstore, but in 2005 it's a little hard to come by.

Re:Kill germs too? (1)

Tlosk (761023) | more than 8 years ago | (#14111717)

Microwaves kill various germs too, don't they? They should market this as both a water heater and a sanitizer.

The linked article is only two paragraphs, the second one was...

"The tankless system uses microwave technology to heat water on demand, saving energy and providing an endless supply of hot water for residential and commercial usage. The technology is designed to eliminate the deadly Legionella Pneumophila, since water will not stagnate, as it does with conventional hot water heaters."

Re:Kill germs too? (2, Informative)

cnettel (836611) | more than 8 years ago | (#14111821)

No, they basically don't. However, as noted, any quick and thorough heating will be quite efficient in killing them. It's relevant to keep in mind that if the system was tuned to say 40 deg. C/100 deg. F, we would get no germ-killing effect at all.

Re:Kill germs too? (1)

njh (24312) | more than 8 years ago | (#14111823)

" Microwaves kill various germs too, don't they? "

No more than hot water. Perhaps you are thinking of UVC? I remember reading somewhere that microwave ovens don't even kill fire ants.

1.2 jigawatts!!!!! (0)

Anonymous Coward | more than 8 years ago | (#14111597)

Will this power my Delorean?

Jeepers (4, Insightful)

Chairboy (88841) | more than 8 years ago | (#14111600)

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.

using a microwave vs. normal heat (1)

r00t (33219) | more than 8 years ago | (#14111601)

A conventional heater should do just fine. If it isn't working, give it more surface area and less mass.

The microwave could be useful with really hard water though. It might not get deposits as much, depending on how it was done.

Re:using a microwave vs. normal heat (1)

ReformedExCon (897248) | more than 8 years ago | (#14111615)

I find the hot water running out after the fourth person hops out of the shower to be rather inconvenient. Gas is definitely the way to go if you can get it.

Microwave might also be good, but should water be superheated to 140 degrees? That's a Fark headline waiting to happen.

Not superheating (1)

ReformedExCon (897248) | more than 8 years ago | (#14111643)

My mistake. I never thought I'd see Farenheit used on a technical message board, so I automatically thought 140 degrees was superheated water.

That'll learn me to pay attention.

Re:using a microwave vs. normal heat (1)

ashridah (72567) | more than 8 years ago | (#14111677)

I find the hot water running out after the fourth person hops out of the shower to be rather inconvenient. Gas is definitely the way to go if you can get it.

You fit 4 people in a shower? I hope they're not family members :).

ash

Re:using a microwave vs. normal heat (1)

advocate_one (662832) | more than 8 years ago | (#14111678)

but should water be superheated to 140 degrees? That's a Fark headline waiting to happen.

YES... cos then the bugs will be killed and won't be around to breed in the water in the line from the boiler to the taps... if you don't heat the water enough, then you WILL end up with things like Legionella. In the UK, we do this shower thing differently, we have the water heater in the shower and heat the water as it is used [mirashowers.com] ... far simpler.

Re:using a microwave vs. normal heat (1)

Supurcell (834022) | more than 8 years ago | (#14111824)

But what if you want hot/warm water from the sink?

Pssh (2, Funny)

doxology (636469) | more than 8 years ago | (#14111603)

From a company with "Pulsar" in its name, I would have expected them to use gamma radiation.

Re:Pssh (1)

kfg (145172) | more than 8 years ago | (#14111805)

Maybe they'll start working on that whan Dr. Banner gets back from vacation.

KFG

Why didn't someone think of it before (0)

Shashvat (676991) | more than 8 years ago | (#14111605)

We've been using microwaves to heat food for years now. How come no one came up with this idea before? Is there a technical limitation that has been overcome?

Re:Why didn't someone think of it before (1)

rvalles (649635) | more than 8 years ago | (#14111619)

Up until today, nobody with enough money to buy a patent came with the idea ;)

Down with the patents!

I agree, and I don't know (0, Redundant)

HvitRavn (813950) | more than 8 years ago | (#14111696)

I was thinking the exact same thing. Microwave technology has been in our household for what has to be more than 20 years now. The potential of using it for other things than heating food should be in plain view.

If everyone swaps their conventional heater with a powersaving microwave heater though, the electricity companies will see a lot less demand for electricity since they obviously consume less power.

Maybe there's some fertile ground for a conspiracy theory here. Gentlemen - fetch your tinfoil hats.

Re:I agree, and I don't know (1)

goldseries (932320) | more than 8 years ago | (#14111810)

This post has a fundamental problem. A gas water heater is the kind that heats water up and holds it hot. The electric water heater is the one that heats water up as it is needed. The limitation of the electric heater is that it can't process large amounts of water at once leading to luke warm water. The limitation of the gas water heater is that it wastes energy keeping water hot all the time and that it can run out and takes a long time to refill. This is an improvement on the electric heater. It can heat larger amounts of water at a time meaning that the water will always be hot with out wasting energy when it is not needed.

Re:Why didn't someone think of it before (2, Interesting)

1u3hr (530656) | more than 8 years ago | (#14111721)

We've been using microwaves to heat food for years now. How come no one came up with this idea before? Is there a technical limitation that has been overcome?

Maybe because it's not really a great idea. MW ovens are efficient because they just heat water, not the air etc in the oven. But an immersed electric element is already very efficient at heating water. If I want to boil more than one cup of water I use an electric heater, or a kettle on a stove. If there is a breakthrough, it would be in making high-powered (by comparison with domestic MW ovens)as cheap than an on-demand electric heater. That's assuming it really is as cheap, if it's not then it's just a novelty item for gadget geeks &/or Japanese.

Re:Why didn't someone think of it before (1)

Kadin2048 (468275) | more than 8 years ago | (#14111735)

Probably because until somebody came up with this application for microwaves, it was a solution looking for a problem. Sure, you could have made a microwave water heater any time between the invention of the microwave and today, but why would you want to? It's not like anyone really has a problem with resistance-coils; they're remarkably close to 100% efficient when submerged in the fluid you want to heat, and dead simple.

I still question their claim (which is their invention's raison d'être, as far as I can tell) that you can't heat water fast enough for an 'on demand' application with resistance coils, because it would take too much electricity. Heating water is heating water -- if you want to do it faster you use more coils, and thus more power, but the power required isn't necessarily any higher than what you'd need to do the same amount of work with a microwave emitter. It doesn't quite make sense to me.

microwaves more than 100% efficient? (2, Insightful)

joostje (126457) | more than 8 years ago | (#14111607)

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.

Re:microwaves more than 100% efficient? (2, Informative)

jimi1283 (699887) | more than 8 years ago | (#14111637)

That's the entire point, there is no tank on this unit. Water is heated as it flows through. Try doing that with resistor based elements and you'll get slightly above room temperature water at best. Microwaves are perfect for this since they hit the resonance frequency of water, heating them very quickly with minimal energy.

Re:microwaves more than 100% efficient? (5, Informative)

1u3hr (530656) | more than 8 years ago | (#14111754)

there is no tank on this unit. Water is heated as it flows through. Try doing that with resistor based elements and you'll get slightly above room temperature water at best.

Really? So none of the electric "tankless" water heaters on this page [plumbingstore.com] actually work then?

Re:microwaves more than 100% efficient? (0)

Anonymous Coward | more than 8 years ago | (#14111801)

The first ones are gas. Read the summary.

Presumably this unit can handle a larger volume of water more efficiently than the rest.

Re:microwaves more than 100% efficient? (1)

1u3hr (530656) | more than 8 years ago | (#14111835)

The first ones are gas.

And the rest are electric.

Re:microwaves more than 100% efficient? (1)

Detritus (11846) | more than 8 years ago | (#14111819)

Microwaves are perfect for this since they hit the resonance frequency of water, heating them very quickly with minimal energy.

No [yarchive.net] , that's a common misconception.

Re:microwaves more than 100% efficient? (1)

whig (6869) | more than 8 years ago | (#14111641)

I suspect that the efficiency of electrical resistance heating is lost to radiated environmental heat.

Re:microwaves more than 100% efficient? (1)

Godman (767682) | more than 8 years ago | (#14111693)

The efficiency may be close to 100%, but that's not what's cool. What would be cool is a method that uses close to 100% of available energy, AND does it really fast.

That's cool. Its like the difference between a car with a v6 and one with a v8. Both might use the same percentage of the energy available to them, but the v8 is obviously faster and more powerful.

Re:microwaves more than 100% efficient? (1)

dougmc (70836) | more than 8 years ago | (#14111813)

but the v8 is obviously faster and more powerful.
No it's not (obvious). The number of cylinders doesn't really matter -- it's the total displacement. Now, if the cylinders are of equal size, then a V8 will have 33% more displacement than the V6, but that's not always the case. But there's no reason why a two cylinder engine can't put out more power than an eight cylinder engine.

(And of course, displacement isn't the only factor either. But it's a lot better thing to look at than just the number of cylinders.)

Of course, even if you'd said displacement instead of V8 vs. V6, your analogy would have still been very poor. V6s and V8s function almost identically. Using a heating element vs. a microwave to heat water, that's very different. Perhaps the microwave can turn on and off quicker, but it will also cost several times as much, be less efficient (than your conventional on-demand water heater) and be much more complicated.

And as for the radiation killing germs, people are confused. It's ionizing radiation that kills germs. Microwaves are not ionizing. You'll certainly kill germs by heating water to near boiling, and not allowing water to stagnate will certainly help (but if you use hot water every day, water doesn't stagnate in conventional water heaters with a resevoir either.)

Personally, this new hot water heater doesn't sound like such a wonderful idea to me. Obviously it works, but it just doesn't seem to be worthwhile. Perhaps it'll be useful in some niche markets, but I don't see it replacing the existing water heaters (either resevoir based or on-demand) in any great numbers.

Re:microwaves more than 100% efficient? (4, Interesting)

G-funk (22712) | more than 8 years ago | (#14111694)

That's if you just count kw->BTUs, but that's not what they're talking about. They're talking about a complete system. You can't heat water efficiently for your showers with coils because they take time to heat up, they waste energy when they're cooling down and you're not in the shower, and because it just takes so darn long to do it without a huge amount of coil (which would use more energy in heatup / cooldown), you have to store it hot. And storing something hot is just about the least effecient thing you can do in this universe, and as such "the system" tends to be quite inefficient. With a magnetron it's not seeping heat into the air while it cools down (well not within an order of magnitude the same amount), it's more or less instant-on. So you're not leaking your power into the air in your heater cupboard and the frame of your house. The only thing newsworthy about this though is that it's taken so long for someone to think up and implement a viable microwave solution.

Of course, my ex housemate ben only knows to get out of the shower when it gets cold, so I apologize for my mate using up all the world's energy when he gets one of these. On the plus side he'll eventually wash down the sink and his missus will turn it off.

Yes, I understand the OP would definitely know all this, and was just trying to make a point, but I just thought I'd elaborate^W ramble a bit with my AU$0.02

Re:microwaves more than 100% efficient? (0)

Anonymous Coward | more than 8 years ago | (#14111755)

I have a great plan. With all that energy saving, we can use the new design of heater to generate steam. Use the steam to power a generator. Use some of the generator output to power the heater, and the rest (maybe half, maybe more) can power other things around the home. On an industrial scale this could have a tremendous effect on the economy!

What a pity the Patent Office explicitly ban the patenting of such devices. ;)

Re:microwaves more than 100% efficient? (1)

reidleake (818488) | more than 8 years ago | (#14111758)

Well their website http://www.pulsar-at.com/ [pulsar-at.com] does not reveal any information.

Maybe this is vaporware.... pun intended.

cost? (1)

castlec (546341) | more than 8 years ago | (#14111613)

so we have a mature technology being applied to a new sector. this has the opportunity to save a lot of us money and also the effort required to keep a pilot going. the question is, will it be offered at a fair price?

Re:cost? (1)

Nos. (179609) | more than 8 years ago | (#14111657)

That's my question. I'd love to replace my gas water heater with a tankless option, but I'm not going to spend twice (or more) as much as a new efficient water heater would cost.

Not true! (3, Informative)

Knuckles (8964) | more than 8 years ago | (#14111628)

You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity

Were I lived (the real world) many people had on-demand heating with conventional gear in the seventies, and still do [plumbingsupply.com] .

Re:Not true! (0)

Anonymous Coward | more than 8 years ago | (#14111723)

My grandmother has been using a conventional electrical on-demand water heater at least since 1950s, possibly even earlier.

Actually... (1)

nipsy (65935) | more than 8 years ago | (#14111630)

You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity.

I'm fairly certain that SETS' [gotankless.com] tankless water heaters do in fact use a conventional electric element to provide heated water on demand. Check out their site for more information, but I've seriously been considering replacing my old water heater at home with one of their products.

Which isn't to say that on demand microwaved water isn't spiffy keen also!

Re:Actually... (0)

Anonymous Coward | more than 8 years ago | (#14111676)

The water is kept heated at all times. Thats why, if you have an electric water heater, you can "run out" out of hot water if too many people shower in a row.

Re:Actually... (1)

nipsy (65935) | more than 8 years ago | (#14111682)

I understand how a truly conventional (read: not on demand) water heater works. But I'm not sure what that has to do with my comment.

Re:Actually... (5, Funny)

MidnightBrewer (97195) | more than 8 years ago | (#14111708)

Most people in Japan have tankless water heaters, which makes sense in a country with a dearth of space and great surpluses of energy. It's just about the coolest thing ever; the element is heated in just a few seconds, and after that it's warm for as long as you care to shower. Combined with the automated bathtub courtesy of Osaka Gas, that fills itself and announces when it's ready in an attractive female voice, and I can't imagine ever going back.

Re:Actually... in Canada, too (2, Informative)

Prairiewest (719875) | more than 8 years ago | (#14111720)

I'm fairly certain that SETS' tankless water heaters do in fact use a conventional electric element to provide heated water on demand.

My Dad works at a place that sells these in Canada, and has been selling them for a while (not sure how long exactly, but well over a year). Not the microwave variety like the story talks about, but the electric variety like SETS. He says they work quite well, but it does take people some time to "accept" them.

There are a decent amount of this variety out now [google.ca] , it appears. And if they're being sold at Home Depot to your average Joe, then I'd say that at least the electric version of this technology is mature enough.

I would buy one if my water heater wasn't working so darn well right now (I hope I didn't just sentence my water heater to a premature death).

Todd

Re:Actually... (1)

Mkx (614118) | more than 8 years ago | (#14111780)

One problem: SETS demands at least 50 amps current. Which is by standards in my countr quite a lot. No way that it much less with microwave technology. And this is the main reason for having water heaters with tanks: you can use low-power (say 6 or 10 amps) heating element and heat water in advance.

Re:Actually... (1)

nipsy (65935) | more than 8 years ago | (#14111802)

It seems like high power draw will be the downside to any on demand solution. But I guess the argument is that over the long haul, the short duration high draw solution is more power efficient than the low draw always on solution of conventional gas or electric water heaters.

Of course, if you don't have a decent electrical grid to draw from, the high current requirement might cause one to have to settle for the old way of doing things.

It is worth mentioning though that the SETS units all have life time warranties, including the heating element, which is a fairly impressive warranty. This is certainly something that no conventional water heater can claim.

Completely useless (2)

raoul666 (870362) | more than 8 years ago | (#14111631)

The article, not the idea. It's two paragraphs, and the company that's developing this thing doesn't even have a website up, other than a big shiny logo.

This is the first time I've bitched about the editors here, but in this case, I think it's deserved. I'd honestly prefer a dupe or something a month old than a story with no substance at all.

wrong! (0)

Anonymous Coward | more than 8 years ago | (#14111635)

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.

WRONG!!

it should be

Well, until now, you had two options: natural gas heaters that keep a large amount of water hot at all times, or electric heaters that heat up water on-demand.

Re:wrong! (1)

deburg (838010) | more than 8 years ago | (#14111722)

Look... different places, different systems. In HK, I'd used a gas-based on-demand water heater.

But at home, I'll use an electric based on-demand water heater, mostly because in Soviet Rus... er... gas comes in small tanks and connects only to the cooking stove.

Here's an example of a electric heater that heats up water on-demand.

http://203.163.64.107/panasonic/storefront/Product Detail/default.asp?ProductId=1784&CatId=21,195,199 [203.163.64.107] >

I understand that some places that has lower off-peak electric charges, the use of large electric hot water heaters is more common, furthermore in winter/cold places, the water is used to warm up the house.

But around where I live, with a flat eletric charges rate, NO winter, and a high household voltage of 220-240 volts and max of 13 amps, so... eletric on-demand water heaters.

Just pray that the heater never short-circuits... or the amps is gonna fry me... :P

The real question is... (1, Funny)

Anonymous Coward | more than 8 years ago | (#14111639)

Why in the world is a new product developed by anybody other than Google?

First seen on "Batman Begins" (1)

NoSuchGuy (308510) | more than 8 years ago | (#14111645)

This device was first seen in the movie "Batman Begins"

How about a cyclotron? (1)

core plexus (599119) | more than 8 years ago | (#14111650)

Some cities may regulate this, as seen by the reaction by the Anchorage Assembly to a home-operated cyclotron [suvalleynews.com] , which they are trying to prohibit. Same for other particle accelerators.

Bummer. If you were thinking of having your own particle accelerator in Alaska, pick another city.

Re:How about a cyclotron? (1)

Leroy_Brown242 (683141) | more than 8 years ago | (#14111692)

Since when did Alaska become a city?

[/smartass]

.

Re:How about a cyclotron? (1)

core plexus (599119) | more than 8 years ago | (#14111746)

Oops, too much Halloween celebration. Or Veterans Day, whatever it was today.

Really, though, Alaska should be a Free Nation.

Free Us!

Re:How about a cyclotron? (1)

Leroy_Brown242 (683141) | more than 8 years ago | (#14111768)

When Alaska becomes it's own nation, I'll be the first Oregonian to sign up for citizenship. :)

Third option? (1)

Stephen H-B (771203) | more than 8 years ago | (#14111659)

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

Here in Australia, many people use off-peak gas hot water. A gas burner runs at times of lower gas demand (when e.g. gas cooking for dinner is not happening) and a tank holds the hot water. Is this practice uncommon in the US or is the submitter just an idiot? (Note: both options may be valid)

Re:Third option? (1)

greginnj (891863) | more than 8 years ago | (#14111700)

Don't know about the submitter's mental capacity, but I believe he switched 'gas' and 'electric'. As for demand-based pricing, it is uncommon in the US. I know it's common in Europe for utilities, but I've never heard of it being used here. We're just starting to experiment with demand-based pricing of highway tolls.

Re:Third option? (1)

m00j (801234) | more than 8 years ago | (#14111788)

I think you mean electric hot water. Basically it runs in the middle of the night when everyone is asleep and all the industrial areas are not using much power either.

Having just built a new house here in Australia we also found another interesting bit of technology avaliable to us Aussies (maybe you can get it elsewhere too). It is a hot water tank but instead of using a standard heating element it uses an airconditioner. The great thing about them is they can achieve >100% efficency (as they are pumping heat from one place to the other). Not so great is that if it gets too cold there is not enough heat in the air to heat the water, but not much of a problem in Australia.

The money you save running one of them hardly makes it worthwile due to the extra initial outlay but it is a small investment in the future, especially considering that Australia burns a lot of coal for electricity.

I believe you may be the idiot (2, Informative)

thorpie (656838) | more than 8 years ago | (#14111791)

Gas on Off peak? Not the I have ever heard of. Electricity on off-peak. By-the by, storage heaters I believe are relatively efficient, the insulation of them is effective so they only lose some small amount of heat in 24 hours (which is why off peak works, because you only heat the water once a day and it stays hot for 24 hours) By-the-by-2 a calorie of energy is going to heat a gram of water 1 degree C whether it is inserted into the water by microwave or by elemnet. A 2 kw electic kettle will heat the same amount of water twice as much as a 1000 watt microwave. 2 kw (or 478 calories/sec) will heat .478 liters of water by 1 degree C per second, so in-line if your cold water needs heating by 30 degrees C to shower you get a flow of less than 1 liter per minute from a 2 kw element or microwave. At that flowrate I would take a book, or a friend because you will be in there a while.

About Effectiveness (1)

VincenzoRomano (881055) | more than 8 years ago | (#14111664)

Why is this cool?
If it is "cool!" is doesn't work!
We all expect it being "hot!"

Intel beats all (1)

charlesesl (917504) | more than 8 years ago | (#14111665)

Any time I am feeling cold, I just turn on my Pentium 4.

forgot oil... (1)

Fouquet (753286) | more than 8 years ago | (#14111667)

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.

We don't have natural gas available where I live, but we still have hot water on demand. It's called 'oil heat', and as far as I know is available most anywhere in the US. Granted, oil has its downsides, but so does natural gas. At least your house won't blow up if you have an oil leak

Free energy (as in beer)? Woo hoo! (1)

Zog The Undeniable (632031) | more than 8 years ago | (#14111671)

You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity

I am placing you under arrest for violating the Second Law of Thermodynamics. You do not have to say anything. Anything you do say will be written down and sold to those guys who spam Usenet with ads for "friction free" bicycle lights.

Wow... (1)

Guru84 (932641) | more than 8 years ago | (#14111674)

I want one! Around here, when someone wants to take a shower it'll be twenty minutes before anyone else can without getting frozen like a popsickle. ...and don't dare think about two people taking a shower at the same time, unless you're going for a thirty second rinse. We have three showers, but the hot water heater just doesn't cut it. It's electric by the way. Maybe I should skip my new computer upgrade to find a new water heater......... nah!

bad science = scam (2, Informative)

frovingslosh (582462) | more than 8 years ago | (#14111698)

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.

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. The thing is, that holds true for any way you try to heat water by electricity, including microwave, not just "resistance-based" heating. Assume 100% efficency; do the math. You don't get more than 100% efficency just because you use microwaves. You'll see that you can't heat water fast enough to maintain a flow rate in a shower. So unless you plan to have a tank of water at each point where you use hot water and heat it a few munutes before you need it, this just doesn't pass the math. And, of course, heating tanks of water all around the house isn't pratical either; if you heat a large tank and then just wash your hair you waste a lot of hot water that will cool down before it is needed; if the tank is not large enough then the flow turns cold long before the shower is over.

Yea, it would be really neat, and I'm sure that some people who really want this will mode me down because they don't like what I'm saying. But the math doesn't work. And I did read the links. Zilch on the official website. The linked article shows no power usage math and get as technical as saying the thing is the size of a "stereo speaker". I have had a lot of stereo equipment over the years but I have absolutely no idea how to translate that unit of measurement.

And yet... (1)

WindBourne (631190) | more than 8 years ago | (#14111712)

there are electrical tankless water heaters

Re:bad science = scam (2, Insightful)

Lynx0 (316733) | more than 8 years ago | (#14111757)

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.

Different efficiencies... (1)

KingSkippus (799657) | more than 8 years ago | (#14111777)

It seems to me that it all boils down (no pun intended) to the different efficiencies between conventional electric water heaters and microwave water heaters.

If the efficiency of a resistor-based electric water heater is x and the efficiency of a microwave-based electric water heater is y, and y > x, then my math says that a microwave water heater is more cost-effective from an electricity point of view and can heat water faster. Neither of them have to be 100%, and in fact, that's impossible. All that matters is that one is better than the other.

One thing I know for sure is that there are existing on-demand water heaters, so I assume the press release means that the microwave technology is cheaper or otherwise better.

I have to admit that I lied about one thing, though: that pun was actually intended. Sorry about that, I promise I won't lie again in this post.

Re:bad science = scam (1)

Tlosk (761023) | more than 8 years ago | (#14111781)

I suspect you must have misplaced a decimal or some such in your "calculations" because what you describe as impossible is a common product used by most households throughout Central and South America. Called a Ducha, it's basically a glorified showerhead with a power hookup that heats the water as you shower.

When the wiring was slipshod and unsightly it always made me think twice about turning it on.

Here's a link if you are still incredulous:

http://www.cpsc.gov/cpscpub/prerel/prhtml04/04044. html [cpsc.gov]

I will supply the hallucinogenic powder. (1)

DroopyStonx (683090) | more than 8 years ago | (#14111702)

The powder will be poured into the water system and then this device will be used to heat the streets of the city, allowing everyone to inhale said hallucinogenic powder for teh win.

Poppycock (1)

elgatozorbas (783538) | more than 8 years ago | (#14111703)

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.

Since Joule we know that energy (e.g. electrical) and heat are equivalent [wikipedia.org] . It doesn't matter how you convert it: bulb,resistor, microwaves...

Re:Poppycock (1)

erikharrison (633719) | more than 8 years ago | (#14111786)

I hate to say it that you do not know what you are talking about (despite being right).

Microwave emittors do not have the same trouble with efficiency that a bulb or resistor has. Microwaves also penetrate far, and thus can affect larger volumes of mass at the same time, this allows a more consistent heat, in a shorter amount of time, more efficiently

Re:Poppycock (1)

njh (24312) | more than 8 years ago | (#14111830)

Well, apart from heat pumps. And yes, you can get heat pump based water heaters :)

Time to Check Up on Aerogel--extreme insulation (2)

icecow (764255) | more than 8 years ago | (#14111704)

Aerogel is an incredible substance made 99.8% air. It's a super insulator (my words). Loosely speaking,it's like Jello in a solid form with the water replaced with air.

Hot water on demand would require a smaller amount of surface area for the chamber, thus less aerogel needed..a cost improvement. Google aerogel--I see some recent articles in the google 'News' tab as well.

Nasa/JPL offers a description here:
http://stardust.jpl.nasa.gov/tech/aerogel.html [nasa.gov]

oh damn (0)

Anonymous Coward | more than 8 years ago | (#14111716)

no longer will my 30 minute showers in the morning mean cold water for the rest of the family.

how much is it? (1)

zome (546331) | more than 8 years ago | (#14111718)

...and the second is not available to everyone

unless it costs less than a couple hundred bucks, it won't be available to anyone.

Electric resistance-based quite common (5, Informative)

Lynx0 (316733) | more than 8 years ago | (#14111732)

You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity.

In a lot of countries (like Germany where I live) on demand electric waterheaters (called continous flow heaters) are very common, especially in apartments buildings where there is no central water heating. They work well, and from the (very old) model I have in my apartment you get hot water in less than 30 seconds. Modern units can be set to a fixed water temperature and hold this even with changes in the amount of water flowing.

Also, as another poster pointed out already, those units do not use up any more energy than other technologies would to heat the same amount of water.

Marketing Crapola! (5, Insightful)

GoRK (10018) | more than 8 years ago | (#14111733)

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.

mod 3Own (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#14111738)

we don't sux0r as Fthe problems Lite is straining

Possible alternative explanation (2, Interesting)

Flying pig (925874) | more than 8 years ago | (#14111763)

As people have already pointed out, if the article is correct this is a device that claims to disobey the laws of physics. (And BTW the microwave conversion will be much less than 100% efficient, so it should work considerably worse than resistance heating.) However, there is al alternative possibility, and its based on the reference to legionella.

Although the actual temperature needed for bath or shower water is only around 40-45C, running at that temperature with a conventional system is dangerous because it allows the growth of bacteria in the system, including legionella. Using microwaves will disrupt all the bacteria and mean that low temperature operation is possible, exactly like using a suspended UV lamp in a conventional cold water recirculating system. If the water has only to be heated to around 45C rather than the usual 60, there will be less energy loss and the volume of water that can be heated will be greater.

However, at the end of the day unless you have a renewables (wind,solar,water) generator, using electricity to heat water is a Bad Thing. By the time it reaches you, the generation efficiency is down to around 30-35% allowing for losses, which means it will always suck badly compared to gas, oil or solid fuel water heating. In terms of sheer efficiency nothing beats a thermo syphonic system running on anthracite - no electricity used, and no water vapor created by combustion to remove latent heat up the stack in steam. A condensing boiler is nearly as good but rarely installed properly. I personally feel the long term energy saving solution lies in more efficient tank heat exchangers with better insulation, and certainly there have been a lot of developments in recent years.

Bogus physics ! (1)

Ihlosi (895663) | more than 8 years ago | (#14111767)

You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity.



NEWS FLASH: Heating water requires huge amounts of _power_ (since it has the highest specific heat of any liquid), regardless of the method used to do the actual heating.



Even if you use microwaves, you'll still need at least 4.19 J/(kg * K).

Electrical Hot Water on Demand (1)

PhotoGuy (189467) | more than 8 years ago | (#14111769)

On demand [tanklesswa...direct.com] electrical hot water heaters (known as tankless) have been around awhile.

Another interesting portable product which I use, and with which I am very happy, is the Coleman Hot Water on Demand [coleman.com] ; this one uses propane and is designed for camping.

Only two ways? (1)

Hektor_Troy (262592) | more than 8 years ago | (#14111782)

So ... the idea of having a power plant heat up water as well and sending it out to households as a sort of ... "central heating" ... and then having a heat exchanger heat the water locally wouldn't work? Say, send out really really hot water and use something like ... maybe a 2.5 liter exchanger?

Nah ... couldn't possibly work. I know we never see stuff like that in Denmark. </irony>

good one guys (1)

know1 (854868) | more than 8 years ago | (#14111784)

this is seriously cool, but not a scientific breakthrough.
i learnt that water was fine in the microwave years ago the first time i had a cup of coffee go cold because i got engrossed in what i was doing.
wicked product though, send me one and i'll test it for you

Story submitter lives 15 minutes from Pulsar (1, Offtopic)

SuperBanana (662181) | more than 8 years ago | (#14111800)

The submitter, whose email address is under the domain name ohgizmo.com, lives at:

Administrative Contact: David Ponce (3M5FU) dponce80@gmail.com 7449 Champagneur Ave. Montreal, Quebec H3N2K1 Canada Phone: (514)586 x 6898

The company's contact:

Pulsar Advanced Technologies Stavros Kottos 8533 Delmeade Road Mount Royal QC CA H4T 1M1 15149314745 15149318755 info@pulsar-at.com

Mount Royal is a borough of Montreal.

Now isn't that just a wild coincidence that the story submitter lives about 15 minutes away from Mr. Ponce [google.com] ? I confirmed Mr. Kottos's address via a Google search on his name [google.com] .

PS: Here's another wild coincidence [slashdot.org] .

Nice name! (0)

Anonymous Coward | more than 8 years ago | (#14111815)

The Vulcanus MK4

Heh, heh. You said anus.

Electric heaters are 100% efficient. (4, Informative)

Futurepower(R) (558542) | more than 8 years ago | (#14111816)

Slashdot editors seem to be taking money to run public relations press releases as stories. Here's a quote from the Slashdot story: "You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity." ?????

The energy to heat water is fixed. Normal electric heaters, called "resistance-based electric elements" in this story, use 100% of the energy to make heat. They are 100% efficient.

A microwave device would waste energy in making microwaves. That wasted energy would be heat, but it might be difficult to put that heat into the water. And why spend more to get another kind of 100% efficiency?

In Brazil and New Zealand, for example, shower heaters are often 220 Volts at 25 Amps. They heat cold water instantly to shower temperature. The heating elements cost less than $10 local equivalent.

Disgusting nonsense quote from the referenced article: "The technology is designed to eliminate the deadly Legionella Pneumophila, since water will not stagnate, as it does with conventional hot water heaters."

Here is accurate information [middlebury.edu] : "Legionella ... requires complex nutritional requirements such as high cysteine levels and low sodium levels to grow. "

You don't get Legionaire's disease from water heaters! The high heat in water heaters kills bacteria. The linked article about Legionella says that it can live in shower heads, but that is at a cool temperature, on the outside.

I Think I Have One Already (1)

Dracophile (140936) | more than 8 years ago | (#14111817)

It's made by Sanyo, and it even has a clock on it...

Re:I Think I Have One Already (2, Funny)

s-orbital (598727) | more than 8 years ago | (#14111833)

I used to have one of these too, until it comitted suicide
http://photos.klassica.com/microwave [klassica.com]

really? (1)

muszek (882567) | more than 8 years ago | (#14111820)

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.

My parents have a bathroom with two "water-heaters", working in exactly opposite manner:
1. an electric one that heats up water on demand (but I admit the water's not too hot, which, btw, saves a lot of water cuz nobody wants to take long showers then :P ).
2. gas-based one that stores some hot water all the time (it's enough for a 5 minutes-long shower).

That's Cool! (0)

Anonymous Coward | more than 8 years ago | (#14111826)

That's Cool!

Waste of good money! (0)

Anonymous Coward | more than 8 years ago | (#14111832)

Heating water with a resistance heater is essentially 100% efficient (with proper insulation and construction). Heating speed is limited only by heater/element contact area and available electrical power. Hasn't anyone ever seen an "insinkerator"? Instant hot water at the sink.

On the other hand, if you are generating microwave energy in a magnetron, the maximum efficiency of power in to microwave power out is no more than 50% or so. The rest of the input electrical power is removed as waste heat by a ventilation fan (for the magnetron), by conduction (for the loses in the high voltage power supply transformeter), etc.

If you don't mind the inefficiency of heating water with electricity (most expensive method by factor of two) and throwing away another 50% of the electrical power as waste hot air, go ahead and pay five times as much for your "microwave" water heater and spend a dollar per shower instead of $0.25.

I am extremely dubious of these claims (2, Insightful)

Andrew Price (757340) | more than 8 years ago | (#14111834)

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

One one hand... (1)

Sockatume (732728) | more than 8 years ago | (#14111841)

On one hand, it may not be much more useful than existing technology. On the other hand... microwaves! I don't know about the rest of you but when it comes to making my home absurdly futuristic, electric or gas heaters just don't cut it.

This story is misfiled! (1)

Deadguy2322 (761832) | more than 8 years ago | (#14111845)

This isn't appropriate for Slashdot! Everybody knows geeks don't shower!!!
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