04-02-13, 11:47 PM | #1 |
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Why You Should Not Use Induction Cooking Technology
This thread is initiated for discussion of why induction cooking technology should not be pursued.
-AC
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04-03-13, 02:03 AM | #2 |
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Branched from other thread
I don't have a link to the thread at my disposal but I remember reading that someone here familiar with electrical utilities said that they just hate induction heating. The reason being is that induction heating presents a firehose type of electrical usage pattern. It requires huge amperages for short time periods. Utilities can cope with medium size variations in loads but if everyone used induction heating it would be similar to every household turning on their electrical welding machine and getting in a little dinnertime welding done at most mealtimes.
The thing to keep in mind about that is that if everyone had that setup there simply would have to be a huge buildup in electrical plants just to keep up with those momentary demands. So, while you yourself would be decreasing the buildup in CO2 in your house, if everyone used induction heating one would be greatly increasing the atmospheric CO2 by using it. Not a good tradeoff to my way of thinking. I wish I had the link at my command. Anyone out there remember that discussion? Last edited by Exeric; 04-03-13 at 02:11 AM.. |
04-03-13, 02:07 AM | #3 |
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When I read that previous thread it was news to me, but I believe it based on the fact that the commenter seemed to know what he was talking about and had some previous affiliation with electric utilities.
Also it makes sense from a physics standpoint if you assume that there is a very low impedance to an inductance stove. Watts and Btu's are not what the problem is about really. It is the instantaneous draw that the utility sees on its resources. It is the reason that particle accelerators have to coordinate with utilities to power them. If utilities had huge banks of capacitors with very low internal resistance there would not be a problem. Instantaneous power wouldn't matter then as long as the total watt hours over, say, any 24 hour period was within the plants capability. I came to the conclusion from that previous commenter, that induction stoves are very low impedance devices that suck monstrous amounts of energy for very short periods of time then shuts off. The iron cookware then retains the heat between the short bursts. If anyone knows for sure about this or if I'm jumping to an erroneous conclusion then let me know. My understanding is that the total amount of heat or btu's are comparable or lower than a regular gas or electric stove over the entire time the induction stove is used. But that is only using the "average", not instantaneous draw. Last edited by Exeric; 04-03-13 at 02:10 AM.. |
04-03-13, 05:25 AM | #4 | |
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Quote:
I am not worried about the CO2 buildup in the house either as I don't think I will ever get it tight enough to matter. |
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04-03-13, 08:46 AM | #5 |
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Exeric,
Let's think about this for a bit. I understand your concern about low impedance loads, but an instantaneous burst of very high current is going to first affect the home wiring. I did check on some new induction stoves this am and looked at total current, peak current, etc. I don't see any of the instantaneous issues. Secondly, I don't see induction stoves as a "cure all". Gone are your aluminum pots as all cooking pots/pans must be ferrous (read expensive). Thirdly, the cost of an induction cooktop is FAR more expensive than a standard resistance one. Long time to pay off any putative savings . . . Lastly, I see all the time of "experts" that comment on issues that are totally wrong. Just recently, a mechanic was quoted on national media that putting high octane gasoline in cars, designed for lower octane, is helpful for the engine and the higher octane "cleans out the engine". Absolute nonsense! Or how about those infamous "power savers" that the electric company does not want you to know about . . . . Not saying you didn't read what you read. But my bottom line impression is that induction cooktops are not going to kill the grid. Steve
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04-03-13, 02:47 PM | #6 |
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It may be that my description of the affect of an induction stove was a bit hyperbolic. But I think the principle behind the description was basically right. Utilities make electrical power as it is used and their design and number of plants are fitted to peak load, not average load. Even if you only double the power required within a 5 minute span due to induction stove heating over electric range heating it will have an effect. If you and all your neighbors that share the 440volt circuit block cook a meal that way from 6:00 to 7:00 PM there is a high likelyhood that perhaps on one day out of the week 33% of you will sychronize over a part of that 5 minutes of most intense power draw. That five minute period, even if it only occurs one day a week will be the new peak that the utility must design for. Multiply that by millions of households in your time zone and the local utility will have a problem.
Like I said (hyperbolicly speaking) the effect would be like everyone firing up the welding machine at mealtime. I think it sounds ridiculous just because no one has thought of what the effect of it might be, not because its an intrinsically ridiculous idea. As far as the wiring go - wire can easily handle peak loads like this as long as it isn't doesn't occur 24/7. It might even be able to handle it then. (After all, induction stoves aren't really welding machines. That was just an illustration point.) |
04-03-13, 05:11 PM | #7 |
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Exeric,
Just how would an induction stove differer from a resistance stove? They both use 220 V lines. As for watts per BTU, they are about the same. Steve
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04-03-13, 05:45 PM | #8 |
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The difference relates to the speed with which pots are brought up to working heat. Although there is some efficiency increase with inductance stoves using magnetic fields most of the speed of temperature increase has to do with increased power usage during the ramp up to that temperature.
Try to think of pulses of electricity instead of average current. During the ramp up to temperature there is one long high power pulse. If a regular electric stove takes 5 minutes to get to heat and the inductive stove takes 2 minutes its not because the inductive stove is 250% more efficient. Most of it, not all, is due to increased power flow during that 2 minutes on the inductive stove. Since peak power usage for a utility is mostly a statistical phenomonon averaged over millions of customers it stands to reason that the "statistical tail" effect of unusual short time span, higher power usage will become more likely. This is especially true since people traditionally cook simultaneously within an hour or hour and a half window within a time zone. In effect, the statistical probability of an overload to the utility mirrors the individual increase in shorter time span, increased power usage in a customers use of an inductive stove. |
04-03-13, 05:50 PM | #9 |
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So, are you saying that it will be less or more expensive to heat with an inductive stove over a standard electric? Assume I will be using all cast iron pots.
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04-03-13, 06:02 PM | #10 |
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It would be cheaper in terms of electrical usage for you. But if everyone had one it would be expensive for society in terms of build up of electrical plants to provide for peak loads.
If utilities ever develop a good and cheap technology to store power then inductive stoves will make a lot of sense because then the lower average power usage of one will actually be useful. Peak power demand wouldn't be a problem. |
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