Indian kitchen, which at one time had very less electrical appliances, is now getting loaded with appliances of all kinds. Ovens: electric or microwave are increasingly getting into Indian kitchen and making their presence felt. But many a times people get confused between the two and do not understand which one to buy. It is important to note that although a lot of activities can be done in both of these types of ovens, there are few things that can be done well only in either one of them. Also efficiently choosing the appliance can also help save some electricity.
How do conventional ovens work?
Conventional Ovens are appliances with enclosed space with metallic elements at the top and bottom. Electric current flows through the metallic elements to heat up the element and in turn the enclosed space and cook food. The thermostat in the oven (if there is one) measures the temperature and adjusts the current through the element to maintain the temperature. Additionally some ovens (convection) also have fans that uniformly distribute the heat. These ovens with fans are much more efficient than conventional ovens as they uniformly distribute the heat and thus can help in reducing the thermostat temperature.
A typical Oven is between 1000 and 2000 watts, but it does not consume all of it during its complete operation. Its electricity consumption depends on the temperature set in the thermostat. Electricity consumption will also depend on the size of the oven and a bigger oven will consume more electricity. We at Bijli Bachao did a test on a small Oven while baking a cake and we found that it took 0.2 units for baking a cake in 30 mins (at 150 degree centigrade). The oven was rated 1200 watts.
How do microwave ovens work?
Microwaves ovens use electromagnetic energy and generate electromagnetic waves that heats up the food kept in the appliance. Unlike a conventional oven, they do not heat up the whole space inside the appliance and just use the waves to heat the food kept in it. Making them much more electricity efficient than traditional ovens. Microwave ovens are also rated less around 500-1000 watts. Because the waves in microwave are concentrated on food, they also cook much faster.
Difference in usage of microwave and conventional oven
Both the types of ovens can be used for heating but have very different purposes. Conventional Ovens are good for any cooking that requires baking or browning of food. A microwave does not bake or brown properly but is good for re-heating, roasting and almost all other kind of cooking. Microwaves are a good replacement for conventional cooking rather than to all types of cooking requiring ovens (like baking).
Cooking and energy efficiency
Electricity contributes very little to the energy consumption in a kitchen. Cooking gas is a major component and we will discuss more on that in a future post. But we would certainly like to point out a few things over here:
- A microwave consumes lesser energy (40% less) than a cooking gas, but cost of electricity is higher than cost of gas.
- Compared to conventional oven microwave oven uses 75% less electricity for activities like cooking a potato.
Myths regarding Microwave Ovens
Some people believe that using microwave ovens contaminates food with radioactive element. But FDA (Food and Drug association) of America states that microwave ovens do not contaminate food. Microwaves just cause water molecules in food to vibrate producing heat that cooks food and thus food having high water content like vegetables cook faster. The energy waves generated by microwave oven are converted to heat and thus they do not contaminate food.
Source of Information
Food and Drug Association website
Home Energy Magazine website
American Council of Energy Efficiency website
Scientific American website
About the Author:
Abhishek Jain is an Alumnus of IIT Bombay with almost 10 years of experience in corporate before starting Bijli Bachao in 2012. His passion for solving problems moved him towards Energy Sector and he is keen to learn about customer behavior towards Energy and find ways to influence the same towards Sustainability. More from this author.