Cooking is not about how fast you can boil water.

I also don't think energy efficiency should be a factor.

Two most important considerations, IMHO, is your cooking style and how important it is for a very easily cleanable stove.

As for your testing, you should get an induction cook top of higher wattage, about 1,800 watts.

dcarch

I have two portable induction cooktops and the Max Burton came with an 8-Inch Induction Interface Disk which enables non-induction cookware to be used on the induction surface, and that may be the quickest "fix" until you get the equipment to go with it. I hardly ever use my regular cooktop anymore, and fortunately my 36-year old Saladmaster Cookware works well on the induction cooktops.

When it comes to heating water, the fastest appliance for that is an electric kettle because the heating element is in contact with the water. When I tested my small appliances using a Watt-A-Meter so I would know the amount of energy and cost to heat 5-cups of water, it took my induction cooktop 8 minutes on HIGH, the microwave on HIGH 13-minutes, and my electric kettle 5 minutes.

Why 5-cups of water? I use 1-gallon of "saved" water for after meal clean-up and washing dishes that don't go into the dishwasher. "Saved" water is the water that generally goes down the drain waiting for the shower to get hot. I heat 5-cups of water in the electric kettle, add 5-cups of cold water and do dishes in a small plastic tub, rather than trying to fill the sink (which takes 3-4-gallons). I use the remainder of the gallon to for rinsing.

-Grainlady

I dabbled with induction hot plates prior to my kitchen remodel when considering it as a cooking source. Your testing methodology is fine; the problem is that plug in electric induction hot plates are limited by the capacity of the 110 volt socket. Most 110 volt circuits can't handle more than about 1800 watts (if you notice, no 110 volt hot plates go more than that).

The built in induction units are 220v and are capable of much more power, and I believe there is where induction shines. (Some 220 induction cooktops have hobs that are 3500 watts, over double the amount of power that your unit can put out) So while those hot plates are convenient, I don't think it's gonna give you the full induction experience. It's still useful--I use mine for frying fish on the back porch--but using a hot plate to evaluate the perfomance of induction is akin to judging automobiles by driving a 1986 Yugo.

There are some 110v hot plates out there a bit stronger than yours (the Max Burton 6000 is 1800 watts, about $75 at Amazon) but at most that would be a 20% improvement.

The link is to a site which tries to list most of the available induction units. There are 220v countertop models (Cooktek, for instance) but they aren't cheap and they require that you run a 220v line.

Here is a link that might be useful: induction site

I don't mean to hijack this, but I have a question about induction hot plates for dcarch:

I have the digital temp controller you talked about when making your sous vide setup. My question: do you think an induction hot plate could be hooked up in a similar fashion? My idea is to make stock very slowly (say, at about 180-190 degrees) safely unattended. Plug the induction unit into the temp controller, dangle the temperature probe in a stockpot (possibly floating it in an oil-filled test tube if it isn't food save) and set it for 190, and let the stock slowly cook for a day or two. Whaddya think?

Arley, probably would not work.

Induction cooktop operations are controlled internally by digital electronics. It requires you to reset cooking parameters each time it is turned off. If your temperature controller turns the induction cooktop off after the temperature is reached, it can't turn it back on again.

You can easily use a cheap electric stove and set its temperature at the highest, and let your temperature coontroller override the stove's thermostat.

dcarch

What grainlady said makes sense; if what you want is something to produce hot water quickly, an electric kettle is pretty quick. There are several models available.

When looking at the induction web site, it turns out there is a 220v tabletop induction cooker at a non-astronomical price. The 3000 watt Athena/Max Burton 'ProChef 3000' is $275 at Amazon, but you'd need to run a 220 line; the total outlay would buy a boatload of electric kettles.

I'm cross posting to Appliances as the OP did.

I clearly have too much time on my hands, so I repeated chas's experiment. I brought 4 cups of tap water (64F according to my thermopen) to rolling boil (201F at our altitude) on our Thermador induction cooktop and the Braun hotpot. On the cooktop, in a stainless pan, it took 2 minutes 3 seconds. In the hotpot it took 2 minutes 42 seconds.

The reason chas's times are longer than mine are because we have 50A available to the cooktop which can deliver around 4.5 kW of energy. I don't recall what the maximum power of the hotpot is. It seems to be higher than the Hamilton Beach chas used.

The 110V, 1.5 kW induction hotplate isn't a good proxy for an induction cooktop. I would use the induction hotplate for supplemental heating if I needed to use a lot of extra pots and pans, but never for my main cooking.

18/0 stainless is commonly used for induction-ready cookware (see link below). Stainless has poor thermal conductivity. Cast iron, while ferromagnetic, is heavy and also has poor thermal conductivity. It heats slowly and transfers heat poorly. However cast iron, once heated, will maintain its heat for much longer than steel. Bottom line - a steel pot will get water to target temperature faster than cast iron simply because it is thinner and lighter. Neither is ideal because of the low thermal conductivity.

I invested in a set of 18/0 stainless with aluminum disc bases, and these work well on induction. Costco sells a set of about 8-9 pots and pans with lids for $160.

Hope that answers some of the OP's questions.

Cheryl

Here is a link that might be useful: induction cookware

This post was edited by jadeite on Mon, Dec 31, 12 at 15:17

To heat 5-cups of water on my induction on high took .15 kW (or 1-cent at our rate) - 8-minutes. The electric kettle took .11 kW. - 5-minutes. Using a Kill-A-Watt meter you can tell exactly how much energy you use and how much it cost based on your energy rate.

I especially like the induction when I need to bring a large amount of liquid/meat to a boil quickly and maintain that for 10-15 minutes before placing it in my Thermal Cooker. Then I finish "cooking" the food without any energy other than thermal. It's estimated you save 80% of your cooking energy using a Thermal Cooker.

Another good point about the induction is that it cools very quickly.

-Grainlady

I've also responded to the OP's post in the appliances forum. For anybody interested, here's the link:

http://ths.gardenweb.com/forums/load/appl/msg1211144220025.html?3

On the question about the Max Burton unit and using its temp control for sous vide, inexpensive portable induction units are not suitable for a number of reasons. First, the temp controls measure the heat of the cooktop surface glass, not the contents of the pan. Second, none of the ones I know of have the accuracy that seems to be an aim in sous vide cooking. Third, all of the less expensive induction units (that I know of) have built in timers that, whether you set them or not, will limit a cooking session to a maximum of three hours or less.

There was a long discussion of this subject over on chowhound earlier this year.

http://chowhound.chow.com/topics/832571

In theory, it should be possible to hack one of the table top units to connect a PID and disconnect the timers, but that requires a fair degree of technical skill because, AFAIK, the tabletop units run via integrated circuit boards. Maybe somebody knows where to find circuit diagrams for the cards?

This post was edited by JWVideo on Mon, Dec 31, 12 at 16:58