How an Induction Cooker Works
Induction cookers use high-frequency electromagnets to transfer energy from an electronic coil to a metal pot or pan. A magnet located under the burner is in contact with an electrical coil, through which current flows. When you put a metal pan on the burner, the magnet and the pan create a loop of current. The energy transferred causes the pan to heat up. The rest of the cooktop remains cool. In fact, even if you slide a piece of paper between the pan and the burner, it won't burn, because the current only works between the metal pan and the magnet. You can adjust the amount of electricity flowing into the circuit, thus controlling the amount of heat.
How a Gas Cooker Works
Gas cookers work by lighting gas on fire and controlling the level of the flame. Gas is fed from a cylinder or gas line into the stove. When you turn on a burner, gas is released from underneath the burner around the burner ring. After the gas has been flowing for a few seconds, the burner lights the gas on fire, heating up the burner ring. To control the temperature, you can raise or lower the amount of gas being released.
Gas cookers can be used with any kind of material used for pots and pans. Induction cookers require pots and pans made of magnetic materials. Stainless steel and cast iron are the most common. If you have mostly aluminum or copper-bottom pans, you will likely need to acquire some new items that will work with the induction cooker.
The induction cooker is a popular choice for families with young children, as there is no way for you to burn yourself on the cooktop, even when it is on to its maximum energy levels--skin simply doesn't conduct the heat the way a metal pan does. Gas ranges, while very safe when used responsibly, do retain the possibility for burns or gas leaks.
Cost and Efficiency
As of May 2010, prices for combined gas cookers and ovens run from about $480 to $1,000. Combined induction cookers and ovens are listed from $1,300 to $3,100. The induction cooker offers more usable space in certain models than the four to six rings of a gas cooker, as the entire cooktop can be used for cooking. The cost to run an induction cooker and gas cooker are about the same in terms of your electric or gas bill. However, the U.S. Department of Energy has determined that the efficiency of induction cookers is around 84 percent, while gas cookers are rated at about 40 percent.