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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."
Another fine product from Wayne Enterprises Military Division...
Now I can have a long hot shower in 30 seconds.
-- I ignore anonymous replies to my comments and postings.
Microwaves kill various germs too, don't they? They should market this as both a water heater and a sanitizer.
Free Conference Call -- No Spam, High Quality
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.
From a company with "Pulsar" in its name, I would have expected them to use gamma radiation.
sigfault. core dumped.
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.
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.
"When I first heard Daydream Nation it quite frankly scared the living shit out of me." -- Matthew Stearns
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.
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl
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.
I'm an American. I love this country and the freedoms that we used to have.
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
Stop invalid scientific research. Ask your local scientists to feed their lab rats with a phytoestrogen-free chow.
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.
"Give a man fire, and he'll be warm for a day; set a man on fire, and he'll be warm for the rest of his life
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, 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
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.
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.
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.
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.
Pining for the fjords
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.
The memories of a man in his old age are the deeds of a man in his prime - Floyd, Pink
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." ?????
... requires complex nutritional requirements such as high cysteine levels and low sodium levels to grow. "
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: "Legionella
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 used to have one of these too, until it comitted suicide
http://photos.klassica.com/microwave
Patent: from Latin patere, to be open
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
Boil t'kettle.
Well, actually, when I was a poor student we did without heating and hotwater because we had a heating shower and boiled the kettle when we did the washing up (once... no, twice... maybe it was only once?).
The problem is interference. 2.45 GHz is smack in the middle of a band designated as a free-for-all, so anyone using it for communications has to accept whatever interference they get. Certifying a microwave to operate in a licensed band would cost far too much for no benefit.
Time is Nature's way of keeping everything from happening at once... the bitch.
- CowboyNeal is a science-illiterate and has no concept of conservation of energy (and should not be editting science stories).
- CowboyNeal is just stupid (ditto).
- CowboyNeal is taking payments to promote fraudulent products (and should be fired).
I can't think of any other possibilities here.Time is Nature's way of keeping everything from happening at once... the bitch.
Its stated in the article that there are two methods.
Method 1 is to heat water and store it and draw it off as needed. In the UK this is usually done with the aid of one massive tank in the roof, to store the cold water for the hot water store. And a second, to store the cold water for the working fluid, which is used to heat the water in the water store. And then of course, there is a third tank, in which the actual hot water itself is stored.
Are you with us so far?
Well, there is a variant on this method, which consists of having a mains fed hot water store. The advantage of this method is that you no longer need tanks in the roof. The disadvantage is that if this tank, which is under pressure, ever blows up, it takes the house with it. A very small chance however.
Method 2 is to heat it on the way through, either by gas fire in a heat exchanger, or by running it over a hot resistive electric heater. In this case you do not have all those hot and cold water stores in your roof space and closets.
British heating engineers have invented a third way. This interesting method has the great merit of being even more more complicated than the multiple tanks in your roof. In this method, you first circulate the working fluid through a tank of hot water, thus heating it up via a heat exchanger. But you do not bathe in this!
No, you draw cold water in a second heat exchanger through that hot water. In this way you have the benefits of both of the first two systems. You have a constant store of hot water in your closet, and two cold water storage tanks in your roof. And, you get to have hot water on demand heated up for you when needed. And as compared to the variant on method 1, you get to have mains pressure hot water, without having a pressurized tank anywhere in the house.
It is very surprising that this system has never been exported.
As others have noted, this microwave heater is a really terrible idea, for many reasons:
- Your basic $69.95 resistance heater does the job with 99%+ efficiency.
- A microwave heater is going to be at best 60% efficient.
- A 20KW magnetron is going to cost serious money!
- A 20KW power transformer is $$$ and heavy too!
- Many houses don't have the extra 40% power available to waste.
Silly, counterproductive, expensive, ridiculously bad idea. Scotty would cry.The thing is, that holds true for any way you try to heat water by electricity, including microwave, not just "resistance-based" heating.
No, no, no, you don't understand. Heat from microwaves is *more efficient heat*. It's like the difference between LEDs and incandescent light bulbs. The LEDs output almost all their energy as light, whereas the incandescent bulbs output light, but they also waste a lot of energy output generating heat.
Water heaters are just the opposite. The resistance based ones are basically just big light bulbs. They heat the water, but they also output tremendous amounts of light, which is completely wasted. (You can't see the light because you don't use transparent pipes, do you?)
The microwave water heaters only output heat (and a little bit of interference with your Wifi network). That's why they're more efficient.
This "article" is a press release being marketed as news by the Globe and Mail. Here is my letter to the editor.
You can get propane fired tankless water heaters, it is not necessary to have piped in natural gas. Go to most any rural hardware store to see them.
As for other alternatives, rooftop solar thermal water pre heaters are also very common, relatively cheap,the payback period is more rapid than about any other alternative energy devices on the market.(I used to sell them, they work great and it is quite possible to build your own at home, as opposed to building your own PV panels which is sort of difficult) And being modular, they can be piggybacked and give you all the hot water you might reasonable want. Basically just big tanks in insulated boxes with glass coverings. They work well in a lot of areas. And you can also get external to the home wood furnaces that produce simply huge amounts of hot water for direct use bathing or washing or for heating the home, using a renewable fuel, or fuels actually, some burn not only wood but corn or entire large custom hay bales, etc.
I once built a small hot water demonstrator that used coils of hose inside of a big woodchip pile in a closed loop cycle using thermosiphoning to transfer the heat. Once it initially heated up due to normal composting action, I got a nice constant flow of hot water out of it.
Plummers make a lot of money for not much work. sounds like he's a smart guy.
Some drink at the fountain of knowledge. Others just gargle.
"...[U]ntil 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."
This makes utterly no sense. Here in the US, and I assume in a fair number of places, we have oil or natural gas water heaters that are hot all the time, and I believe I've read (in the Whole Earth Catalog) of oil on-demand heaters. In either case, drive around outside the big cities, and you'll see house after house with 550 gal. propane tanks, like the one we had in our immobile home 19 years ago.
"Natural gas not available outside cities"?
mark
...that conventional storage water heaters are a religion. I have rarely seen so much energy and emotion expended as their adherent do to fight the evil that is tankless water heaters.
I think you ought to research your claims before posting here. Instantaneous electric water heaters have been around for years. My mother uses a SETS instantaneous electric water heater to supply water to her entire home. Other examples of tankless electric units include remote washrooms to save on the piping, etc.
Please note that I didn't claim that electric water heaters were 99.9% efficient, I just claimed that 99.9% of the energy consumed by one would actually end up inside it. Obviously, any water heater that incorporates a buffer tank will have some standby losses. Please also note that some instantaneous water heaters have standby losses due to their use of standing gas pilots (common on older systems).
Most significantly, I urge you to research the minimum flow requirements that all instant units impose. If you have a whole house instantaneous water heater, it may be very beneficial to have a small buffer tank to cover low loads like a single faucet being cracked open enough to cause flow, but not enough to allow the water heater to fire.
What you're also missing is that the energy distribution companies are gearing up to disincentivize instantaneous gas and electric water heaters, whereever they are attached to their networks (i.e. methane and electric, LP is a different animal). That's because many distribution networks (gas or electric) cannot handle huge spikes in demand, and instantaneous water heating units do exactly that, creating predictable spikes in the morning and in the evening. How will they kill instantaneous units? Simple, peak demand metering.
Utilities and their distributors prefer the slow,steady demand that a low-recovery, buffer-tank water heater imposes on their systems. As meters get upgraded (and ours just did), the utility company not only knows how much you consume, but when you consume it. Demand metering is already standard practice in the Commercial arena (with VERY heavy-handed penalities) and it's only a matter of time before the distribution companies will try to impose the same kind of demand-control on the residential side of the business.