Which is more energy efficient: Coil (Electric stove) or Microwave?

Question

You can add gas also to the list, if at all it can be compared in understandable terms

To be more clear, I would like to compare efficiency in terms of cost, energy consumed per unit of heating (meaning, to get a given item to a particular temperature), and amount of heating per unit of time. Well, if it's all too much, I would just like to know if I will be better off using my microwave than the coils, because in NJ PSEG kills by its electricity bills!

Answer 1

You are comparing apples and bananas.

Gas and Electric stoves work by creating a flame or a coil of hot wire that substitutes as the flame. The flame itself is more efficient, so gas is more efficient than electric. Both of these methods work just like a normal fire from cave man time’s work. They use a direct application of heat. The microwave tries to heat the food from the inside out.

To heat a coil takes a lot of voltage and a lot of amperage. The normal voltage in a US house is 110-120 volts. For an electric range a special connection with twice the voltage is required.

Microwaves are basically a radar set that is aimed at your food. It broadcasts electrical energy in the air down to the food. This is very inefficient, since you are converting the electricity to microwave energy, you are broadcasting it and there is an air space between the heating element and the heat source.

But, microwaves work on a different principle than standard heating like a stove. Microwaves accelerate the movement of the water molecules inside the item thus generating heat all throughout the item. Of course less energy hits the interior, but the energy is applied not just to one side, but to the entire object that is being heated.

Microwaves operate off of normal household current so they require less electricity than the stove therefore they are more energy efficient than the stove, but they heating method is entirely different. It is easier and more efficient to boil water on a stove than it is in a microwave, but when you are defrosting food the microwave is more efficient. When you are cooking food it depends on how much water is inside the food. Moist chicken will cook better than dry chicken, but the food won’t cook that evenly because the energy is absorbed by the outer area and a lower energy amount penetrates the food. With an oven, stove, or flame heat the food is heated uniformly in layers. Each layer is heated to the same temperature and then the heat is radiated to the layer above it. Since the heating is uniform and predictable it is much better to cook over a stove than with a microwave.

What makes microwaves so useful is when you have frozen foods like TV Dinners. These, already cooked meals, just need to be defrosted and a microwave can do that more efficiently than the stove or the oven can.

In order of efficiency the gas flame is the best, followed by the electric stove and then the microwave. But, the heating job varies and the efficiency varies with the job. Microwaves defrost food better and have a hard time boiling water. They don’t cook food as uniformly as a direct application of heat does. In this case your comparison breaks down.

Another problem with the microwave is that it takes longer to get a high heat inside and it can’t brown the food. Some microwaves contain an electrical browning coil just to do this. The microwave works on a different principle in a different manor so comparison to direct heat is difficult.

Answer 2

Energy Efficient Microwave

Answer 3

Inefficiency is the loss of energy in the form of heat. For a heater this means they are all 100% efficient.
Microwave are more effective at heating certain types of food, less effective for others.
If you have a gas stove that is not 100% efficient then you have unburned gas or carbon monoxide escaping into your house.
Efficiency is a comparison of effect to a theoretical perfect cost. The perfect cost would need to be defined first.
Gas is usually cheaper per BTU than electricity.
Edit:
Microwave ovens work by heating the water in the food.
Usually the microwave is the cheapest because only the food gets heated and not the surroundings.
It is only good for heating though and not always the best choice for cooking, Browning foods (caramalization) can improve the taste. Most vegetables do well in the microwave as they are usually only steamed or boiled anyway. The microwave oven can give finer control so they do not end up mushy.
A rotating platform in a microwave oven will heat foods more evenly.
Cooking is an art form.

Answer 4

The electric range element spreads heat all over the place, and wastes about 80 percent of it. The magnetron (microwave generator) focuses a small amount of energy in a small enclosure, making much much more efficient use of the energy.

Answer 5

microwave...heating a coil is very inefficient...natural and propane gas has gone up so much ,mike is your cheapest...

Answer 6

My guess would be microwave, but that is a guess.