However, recent discussions with professional cooks and their positive experiences with induction cooking intrigued us. Induction cooktops are the most energy efficient on the market (CEE Tier 3) and if we ever wanted to convert the house to 100% solar at some point in the future (eliminating the use of propane), this would be the best choice for us, So, it was at this point we decided to do a deep dive on induction cooktops.
Typically cook surfaces are divided into two categories: electric and gas. However, this is a bit of an over-simplification in that these categories only describe the input of the energy needed to ignite the stove and heat the cooking elements, typically referred to as burners. These burners heat the cooking vessel that is placed upon the burner which in turn heats the food inside the cooking vessel. In an indoor environment, some stove tops offer griddle and grilling surfaces, but with these exceptions, all other foods are generally cooked on a burner inside some type of cooking vessel.
An induction cooktop has a ceramic surface that contains one or more powerful, high-frequency electromagnets depending upon the number of burners. The electromagnetism is generated by sophisticated electronics in the "element" under the unit's ceramic surface. When a good-sized piece of magnetic material such as a cast-iron skillet is placed in the magnetic field the element is generating, the magnetic field transfers, or "induces", energy into that metal. That induced energy causes the metal of the cooking vessel to become hot. Controlling the strength of the electromagnetic field controls the amount of heat being generated in the cooking vessel and that amount can be changed instantaneously. One of the distinct advantages of this magnetic induction is that only the point of contact heats. Once that point of contact is removed, the heat generation ceases immediately.
Induction cooking was first introduced to the world at the 1933 Chicago World's Fair, but the cost of the materials and manufacturing for induction stoves was quite high. Therefore, for the next 40 years, induction cooking was primarily used for industrial applications. In the 1970s induction cooking became popular in Asia and Europe where the cost of energy is quite expensive compared to that of the United States and the energy savings versus the cost of investing in an induction cooktop made more sense. However, increasingly energy costs in US energy prices has led to a recent resurgence in interest in this type of cooking. Induction cooking has huge advantages with single and dual burner options and are frequently offered in portable styles making them much more prominent in environments like food trailers.
Advantages of induction cooktops
Because induction offers high-powered cooking, instantaneous heat control, a surface area the cools immediately upon removal of the cooking vessel and a slick, easy-to-clean surface, an induction cooktop is certainly worth a closer look. The burner cools to the touch in about 6 minutes, compared to about 13 for gas and 24 for a regular smooth top. If you accidentally touch the "hot" burner with your hand after you take off the pot, you won't get burned.
Induction cooktops offer the highest efficiency of available technologies at ~90% versus 25-40% for gas and 60-65% for traditional electric cooktops. Traditional electric and gas don't transfer heat only the cooking vessel; whereas, induction only transfer heat to the cooking vessel. Therefore, you use much less energy because there is much less waste heat generated which also results in less energy required for ventilation. Compared to gas cooking, the reduction in ventilation is even more dramatic since you do not have the byproducts of combustions to eliminate such as carbon dioxide and carbon monoxide.
Lastly, models may either offer traditional knobs or touch-sensitive controls that are built into the ceramic top. The built-in controls take a bit of practice operating, but certainly make clean-up much simpler and are one less thing to contend with on your cooktop when you have a lot of dishes being prepared at once.
Disadvantages of induction stove tops
The largest potential disadvantage of induction cooking is you may have to replace or supplement your cookware. Currently, all induction cookers require that the exterior of all your cooking vessels be of a magnetic material such as iron or magnetic stainless steel, that will readily sustain a magnetic field. If you aren't sure what kind of metals are in your cookware, and sometimes it is difficult to tell, an easy method is to get a kitchen magnet and see if it will adhere firmly to the bottom of the pot. This is a bit of a hurdle for our considerations in that most of our cookware for our goat milk products are made from non-magnetic stainless steel and we would need to upgrade some of our pots to induction. Materials like aluminum, copper and glass are also not usable on an induction cooker.
You do not have to go to top-of-the-line names like All-Clad or Le Creuset, for many very reasonably priced cookware lines are also perfectly suited for induction cooking. One of the pots we tried the magnet test on - and was the most adhesive - was an inexpensive Ikea pot. However, if you are considering induction and have a lot invested, literally or emotionally, in non-magnetic cookware, you do need to know the facts.
I've also read about difficulties with certain cookware not making contact very well on particular burners on the stove top, but not with others. I imagine this is the result of a malfunctioning burner that needs to be brought to the attention of the manufacturer and could certainly happen with any type of cooktop.
Another hurdle that is a bit concerning for cooks is you have to re-learn all those years of mental math that you have applied to traditional cooking methods. Some induction cooktop manufacturers claim that water will boil in 90 seconds versus 5-6 minutes on traditional cooktops. This is of course dependent on the magnetic properties of the cooking vessels. The greater the strength of connection in the magnet test, the better the heat transfer with induction. This means that if you're used to the inefficiencies of traditional cooktops, you will need to adjust for greater heat transfer. For slow-cooking foods like eggs and sauces, you will want to keep a closer eye on your cooking. While the saying "a watched pot never boils" may have been true in the past, the rule of thumb for induction should be "an unwatched pot boils over."
Induction cooktops are still fairly new in the US market, and prices have decreasing rapidly as more manufacturers start to make induction available to the broader market. Most manufacturers offer induction as an offering in their top-of-the-line class of kitchen appliances. The difference in the price between a traditional high quality gas or electric cooktop and induction cooktop seems to be about on par. When you factor in the cost of energy to operate the respective cooktops, induction offers savings due to greater heat transfer efficiency and reduced cooking times.
What future capabilities are anticipated?
Furthermore, newer designs and technology primarily out of Europe offer features such as zoned induction. Zoned induction cooktops dispense with the idea of round burners and turn the whole cooktop surface into an induction zone. It seems there are a couple of European manufacturers experimenting with this concept. There is a really good explanation of this concept here. Another technology is also being developed that will allow the use of any type of cookware, whether made of magnetic material or not. However, this technology still seems to be a few years away.
There is also now such a thing as an induction oven. Supposedly it looks as if the usual heating coil on the base of the oven has been replaced by a ferrous plate, which is energized to heat by embedded induction coils beneath it--so any sort of bakeware will work in it, but I haven't been able to find more details than that.
When and where to buy?
In the United States, in the March time frame new models start coming in. You can either get ready to take advantage of the latest and greatest features and capabilities or take advantage of reduced prices as dealers sell off displays in anticipation of new models arriving.
As for where to buy induction stoves, it seems that most stores that carry appliances offer at least one type of induction stove top which is sometimes on display on the showroom floor. Check the internet and talk to people to learn more about what options might best fit your needs.
My existing cooktop still has some life in it and I'm intrigued by the future of induction stoves. Ideally I would like to find a solution that allows me to still use my fabulous copper cookware, so I may seek a hybrid solution that we will have to customize ourselves, but I do see an induction cooktop in our future.