Induction Heater

And thats how you pulled my leg.Comeon man i want to know how its cost effective.My neighbour got it but his bills are normal.Just curious about the technology.

YOU SAID IT ALL!!!

Nothing left for the rest of us, thats just plain boring!!!

GA, well put!!

The rating "3000 Watts" should relate to the absolute capacity of the device to consume/provide heating effect to whatever you are working with.

Provided there is some "regulation" like a thermostat or some other controller, the actual energy used will depend on the energy loss from the air/item that you are heating.

There are many ways to decide what best suits each individual application, like heating response time, maximum surface temperature, physical size, ease of instalation, ability to remove during times when not needed and so on.

Your selection will depend on your specific circumstances. Induction heaters are OK, but so are reverse cycle (heat pumps), radiant, "fan" heaters and even my dealy beloved wood burning heater.

It will never consume more than 3000W. The actual consumption will depend on the comfort levels you set it at and the heat that you allow to escape from the area being heated.

Very GA....I think though 1000 watts of growing up is not enough. I think that the guest poster should get 2500 watts of growing up......since I heard that its really like getting 3000 watts of growing up.

That was logistics

3000W x 4h/day x 10 moneys per kWh = 120 moneys per day. 2500W x 4h/day x 10 moneys per kWh = 100 moneys per day, however, to do the same amount of heating as the 3000W heater the 2500W heater needs to be on for 4 x 3000/2500 hours per day, so the moneys per day ends up the same. It's that simple.

I tried wiki

What are you heating?

If this is a pan then the seller is right, in as much as the induction heater only heats the pan, not a hotplate which has to then have that heat transferred to the pan, thus it will be more efficient.

Since 4 hrs seems a long time to have pans on the boil (unless a commercial kitchen) then what else are you heating?

Capblanc.

wrong

I'm trying to stay focused only on the facts, guest.

I chose to overlook the poor response (from guest) to the first reply and tried to offer some clarification, but again the reply (from guest) was less than courteous. I choose to retire from this thread.

Good luck with your adventures, not only in this issue, but in all things where you need to interact with others providing their input to you as an individual who has requested advice and feedback.

Sorry buddy. It was just a question i expected a direct answer. Too much of expectation may leads to disappointment. Sorry to take away your time.

Depends what you want, If you want something almost has good as gas in cooking then go 3000watts.If you cocerned about cost then go a lower wattage.Ultimately a stove top is for cooking and is going to cost you. WAy out you options good meals vs cost.

Priceless

Guest; the induction heaters that I wired had a water cooled vacuum tubes & used to heat up crankshafts red hot in a matter of seconds & then water sprayed on the crank shaft to harden it. 3000 watts RF was maybe 10,000 watts input. perry

guest; are you talking about electric range in your kitchen where you use magnetic cook ware? perry

Perhps the GUEST should explain about his INDICTION HEATER. INDUCTION HEATERS I know - are used to melt metal . . like gold to cast some jewellery or teeth . . . Thus they are used only minutes every hour . . .

The work crucible - would be only a small ceramic cup (50 mm diameter 50 mm high). The metal placed int eh cup would melt in a few minutes . . . if there is >NO LOAD< int eh cup . . . the heater does not use much power - likely a few hundred watts.

SO, it is up our GUEST to describe what he has . . . and how he intends to use it. . .

Oleh

Sir,

I perceive a problem with saying "all electric heaters are equivalent". Earlier in this thread a post mentioned in passing the difference between radiant and space heating. If one is using the wattage to heat a radiant surface, then a large portion of the heat output is heating objects within the direction the heater is aimed. Since air is a very poor absorber of radiant heat energy, the air temperature is only changed as the surfaces absorb the radiant energy and then by conduction and convection transfer a portion of this heat back to the air. Thus, a very significant portion of the total energy usage goes to the desired heating of objects and people. Many heaters are designed, however, to heat the air--often called space heaters. They do this by conduction and convection. The heated air then circulates to lose some of its heat by the same means onto objects and people. In an area with very little air flow in/out, space heating and radiant heating may be close in their effectiveness. However, in any area that is quite large or has air flowing through it, radiant heat is much more effective in heating the objects and people therein.

I wish the OP would respond to the questions for further information. I suspect the marketer of the product is using terms that are within the realm of technical correctness, but in a way that is (at best) misleading.

--John M.

I beg to differ with your response, and although this is not very academic, I would site the many infomercials touting the "new money saving direct heat cozy infrared and magic box electric heaters" as confirmation of this folly.

These heaters are not more efficient at converting electricity into heat, and if a person turns off their heat pump, which is heating 3 rooms, and uses a radiant convective toaster, wood stove, etc. they may in fact save some money. But no where in that equation is higher efficiency or effectiveness. If you would like to make the point that people can change their behavior, ie sit close to a radiant heat source, and use less energy, that is true.

Finally, I have an Jotul woodstove, an electric heat pump, a forced air NG furnace, radiant tube in flooring, powered by an evacuated tube solar array and backed up by a high efficiency boiler. They are all in a verygood(in the newest highly insulated addition) to just ok(in the original plaster walled 1951 portion) envelope. The radiant flooring is great in the living room, not so great in a busy entrance mudroom. The woodstove is very nice, but tends to be cloudlike in its effectiveness, causing thermostatically driven alternate heat sources to be a little confused.

Resistive electrical consumption is what it is. Changing the circumstances of its production, or the location, does not change that.

Sir,

I appreciate the politeness of the rebuttal. It appears that your experience shows a mixed "bag" of results with the different methods of heating. This does not surprise me.

I stand by the principles I named in the earlier post, but would agree that many applications do not fit into a single label of heating type. At times, the marketing of a product uses a term to describe a portion of the product's operation but is totally wrong when looking at it as a whole. Consider heaters that contain infra-red light bulbs inside their cabinets. They shine this light onto the fins and surfaces of an absorber mounted a few inches away within this same cabinet, and then blow air across this absorber surface. The label says this is a radiant heater (the light bulbs). The design causes the heat it puts out to be almost entirely convective. The energy consumed is the same, even though the label is wrong.

Let me point out an example of a truly radiant heater application. An induced draft blower at the discharge end of a long black metal tube, with a gas-fed flame heating the air that enters this tube 20 to 40 meters away. Above this tube is a concave reflective surface, so the radiant energy is primarily directed downward. It is mounted 4-5 meters above the work area's floor line. The air temperature is perhaps 10 degC, but the workers are comfortable because the tools and machines they touch are closer to 20 degC and their skin/clothing is warmed. I have occasionally worked in such an environment. Here, the energy consumed is much less (an open-floor high-ceiling work space wherein heated air would simply be dissipated into the much greater area that is unoccupied by people).

Thanks for your input--JMM

Thanks imueller, for the info, I really enjoy learning about all of the great apps for energy use reduction.

I have seen those devices in example, in several outdoor eating areas, as well as in a very high end apartment. Lovely device, but is GAS powered heater. The combination of delivery methods is outstanding.

Hi John,

You wrote: I perceive a problem with saying "all electric heaters are equivalent".

I agree. If I had some idea of what the OP is trying to heat, then I'd be more specific. My guess is that he is trying to heat a space... although an induction heater would be an odd choice for such purposes. An induction heater would also be an odd choice to use as an infrared heater.

So my answer is a simplification (the quick answer) aimed at dispelling the myths that oil filled heaters, or ceramic heaters, (or an induction heater heating a pan on a stove to, in turn, heat a room) differ in efficiency (as space heaters) from one to the next.

I wish the OP would respond to the questions for further information. I suspect the marketer of the product is using terms that are within the realm of technical correctness, but in a way that is (at best) misleading.

I think you are exactly right... But then maybe the OP is melting tiny amounts of steel in a lab...

It's a little like buying an automobile with a 500 hp engine and assuming you will get poor mileage. 500 hp is the maximum power output, or in your case 2500 watts is the maximum power dissipation. The actual power dissipated will depend largely on how efficiently you design your heating coils and the physical properties of the parts you are heating.

I guess there is some technology in induction heating rather than resistive heating. See as in case of sound we say 5000watts,there must be a technology to minimise input energy in my kitchen.

No it is not.

The rate of dissipation from the loaded electrical device is not relevant to efficiency. when you are producing heat through electrical resistance or inductance. 1KWH = 3412 BTU. A hot plate and a quartz tube heater have almost identical heat producing properties, per KWH, varied only by light production.

The 500 hp car has different efficiencies depending on the load, temperature, fuel, etc. 1 HP through 500 HP.

That is not the case with electrical energy.

The analogy works. In terms of horsepower, My car might require 30 horsepower to propel it at 60 mph on a level road with no wind etc. Another vehicle may be able to go the same speed under identical conditions but require only 20 horsepower. An 18 wheeler may require 100 horsepower to do the same job. Assuming identical efficiencies of conversion of fuel energy to horsepower, the vehicles will get different mileage. On the electrical side, the RF induction generator is coupled to the load by transformer coupling. The generator is direct coupled to the transformer primary and the part being heated is the secondary. As you increase the distance between the primary and secondary, you loose magnetic flux lines and the coupling becomes less efficient so it requires more watts on the primary to achieve the same results on the secondary. Resistance heating is similar. You can dissipate 2500 watts and have almost no temperature rise or you can operate a huge searchlight with the same power.There is a reason why 1 horsepower = 745.7 watts.

I'm not familiar with this concept.

Does anyone else think that you can dissipate 2500 watts with almost no heat gain by relocating the coupling? If you start to lose conductivity, the load also gets reduced.

There ain't no free lunch, as in, just because I'm farther away from the ball, it is not easier to push it up a hill.

The reason one horsepower = 745.7 watts is the same reason 3412 BTU's = 1KWH.

You can reason that 1HP = 2542 BTU's. You cannot consume 2500 watts without doing work (HP) or making heat (BTU's)

It is not possible to dissipate 2500 watts and have no heat gain. If the primary and secondary are in the same room, (who knows what on earth the OP is talking about?) then any dissipation is heat. Magic doesn't really work.

Assuming identical efficiencies of conversion of fuel energy to horsepower, the vehicles will get different mileage.

However this is an invalid assumption, even if we ignore the truck's diesel and the cars spark ignition engines. The efficiency of engines varies dramatically with load as a percentage of the engine's peak efficiency design load. So a Prius engine (which has a peak efficiency of 38%) operates at relatively close to that peak much of the time because 1. the engine is small, relative to the car 2. it never idles, and 3. when its load would otherwise be light (low efficiency) it is loaded to charge the batteries, which improves it efficiency.

When a typical car engine is operating at 5% of maximum hp (e.g. 500 hp engine at the 25 required to get around town) it operates at very low efficiency. Thus, an Aston Martin DB9 gets 11 MPG around town, whereas a Prius gets 50mpg -- nearly a 5:1 difference in consumption.

Electric resistance heaters, however, operate at essentially 100% efficiency all the time. It is not more efficient to use a small heater running all the time vs a large one cycling on an off.*

* This ignores slight excursions from setpoint temperature, which is a reasonable assumption. These excursions cause very slight differences in system efficiency, (from greater losses from larger temperature differentials) but were talking about a couple percent, not the hundreds of percent differences you see in engine operating efficiency.

You are correct, but missed my point. I was attempting to explain how power dissipated electrically or mechanically can have totally different results depending on the load. 2500 watts dissipated in a lake will not result in a measurable water temperature rise. 2500 watts dissipated in a hair dryer or toaster will get the filaments pretty warm. The equivalent horsepower (3.35hp) probably won't move a truck, but could power a bicycle.

So what you guys want to say.Does a coffee making cost me double or shall i go for numericals related to KJ and calories?Does the frequency converted in modern heaters.

I gather you are using one of the on-line translators to make your posts. They don't always work well. From this end, what you wrote comes out a is gibberish.

I think you may be asking: Does it cost twice as much to heat water for coffee when you use a conventional electric stove as it does to perform the same job with an induction burner?

The answer is no. Per the US DOE, induction heaters are 84% efficient in getting heat into the pot; conventional elements are 71%. These figures are just guides, because they depend on the fit between the burner and the pot. A large, flat pot on a small flat conventional burner is more than 71% efficient. In both cases, the waste heat goes into the kitchen, and in both cases the coffee itself eventually cools, heating the environment. If it is winter, this waste heat helps heat the house, so the difference in electrical bill would be insignificant.

The main advantage of induction cookers is convenience and controllability. The pot can change temperature very quickly, so it is more like cooking with gas. The burner can also shot off automatically if the pot boils dry.

You are incorrect.

It will deliver exactly 2500 watts, the size or magnitude of the load does not matter, nor the size of the lake,truck,bicycle etc.

If you are saying your point is that it takes more power to move a truck than a bicycle, well I'll give you that one. Good point.

One last time, I agree, 2500 watts is 2500 watts. However the affect of that 2500 watts depends on the nature of the load. 2500 watts dissipated in an ocean will not have a measurable effect. That same 2500 watts dissipated in a human body could result in death.

PFR,

I suggest a slight rewording: "It will consume exactly 2500 watts, . . ."

However, when you are looking at the transfer of that energy to the desired target, the efficiencies will vary. A heat pump can transfer (depending on the temperature gradient involved) anywhere from 1.0 to 4.0 times the energy input. It is the only one that has an efficiency higher than unity. In a well-insulated and relatively air-tight space, all the heater types will ultimately transfer virtually 1.0 times the energy input to the space. If the desired target is an object within the room and the room is not an ideal space (heat loss through convection, conduction, and radiation), then the efficiency of heat transfer will be lower. That is why different types of heaters will perform better, depending on the conditions.

For heating a pot of water on a stove, induction heaters are probably the most efficient (I believe 71% has been quoted elsewhere in the 'blog). For heating people in a drafty room, radiant heaters are probably the most efficient. And so forth.

You will consume the same amount of energy, but you probably will get different amounts of benefit from this consumption, depending on the details.

Thanks for listening--JMM

There is NOTHING that provides efficiencies higher than 100% . . .

What you are writing about is the "Coefficient of Performance" (COP),

which is considerably different from "efficiency".

Oleh

Ok guys here ends the discussion.You guys are more concerned about thermodynamics and i am happy to be in the forum very different from your thoughts.

I am a little non plussed about the use of induction in warming a room. I just have one question - HOW?

I use induction for cooking - REALLY like it, so does my wife. But its only a super duper stove top, it is not used in ovens - which are more like (small) rooms to heat I suppose! There are no induction ovens for domestic cooking that I heard of.....

I have heard of induction being used to heat treat the teeth of saw blades and the business end of screwdrivers etc..

But how does this technology heat a room?

I know I could do it, but why invest in the electronics and a thick plate to warm up, when with a (lighter) resistive heater I could do the same and it costs less to buy. Or a radiant heater, maybe even use less electricity.......who know?

For heating air, what we probably do at least 50% of the time, a simple fan driven resistive heater is hard to beat (if its got to be electrical)? All losses are also heat.

Perhaps someone can explain fully, I just think its a marketing trick to sell more and more expensive units.....that have far more bits and pieces to go wrong at exactly the most awkward time....

The OP guest, whose question is nearly impossible to interpret, appears to have been referring to a cook top. He appears to be the same guest who referred to making coffee, which serves as a hint to WTF he might have meant.

For anyone who has a real interest in induction stove tops, start here:-

http://cr4.globalspec.com/thread/12762/Temperature-Control-and-Induction-Cooking

There are some more more blogs about on CR4, just search using "Induction".

Hai

At last nobody given the answer . Our guest asked what will be the power consumptlon per hour?where is the answer for that question?

If it is 3000 watts, the power consumption is 3kwh/h, which, lo and behold, reduces to 3000 watts. The OP already gave that answer. Jeez, can't nobody do arithmetic no more?

Steady up, it was only a dumm guest..........what do they know?

Good point!

The math works only if he is using the "stove top" at the highest setting constantly.

By the way, as he never mentioned as to whether he cooks(?) at full power all the time or not, the consumption is impossible to work out. Generally speaking full power is used to start and then a lower setting to actally cook....

The best way to find out is one of these plug-in "Power used" meters that monitors the power and gives a final amount of electricity used. They cost from about US$30 upwards.

Please re-read the original post. The OP's only question is: "Any idea on this product?"

The OP has not cleary stated what "this product" might be.

I think the OP was clever enough to find us once only........

I'm off.....Byeeeee

Induction heater will directly heat the cooking pot and the water in the pot to make coffee or tea. A resistive heater or gas stove would waste lot of heat in the process by way of convection and radiation. This means reduced energy consumption in case of induction cooking. I have used this and noticed the reduced energy consumpton for cooking purpose. But when there was no water/food to be cooked, the container was over heated and distorted.

I want to know how induction cooking compares with Microwave cooking in terms of energy consumption for identical load.

Rajesh

A resistive heater or gas stove would waste lot of heat in the process by way of convection and radiation.

That depends upon your definition of "lot." With induction cooking, the pot becomes very hot, and radiates heat into the kitchen, and the food itself radiates heat into the kitchen. The difference is between 71% efficiency vs 84%, but even that difference can be misleading: a large flat pan on a small resistance burner causes very little convection. Further, in a cold house, it makes no difference because what is waste heat at the stove serves beneficially as space heating.

But when there was no water/food to be cooked, the container was over heated and distorted.

This should be detected by the stove, so that the burner automatically shuts off when the pot boils dry.

I want to know how induction cooking compares with Microwave cooking in terms of energy consumption for identical load.

If by identical load, you mean the same quantity of food to be heated, the two are close: boiling a liter of water takes about the same energy either way, with the advantage going to an induction heater if the pan is small relative to the amount of water heated.

Microwave ovens are less efficient (70% or so), than the conduction alternatives, but the food is typically more precisely heated. For a cup of tea, the microwave heats only the precise amount of water used, and the cup's heat helps keep the tea warm. The container for the water on a stove is heated and that becomes waste heat, because you do not drink directly from that container. You are also likely to heat more water than you need. Again, these issues make little difference if it is cold out.