Your microwave is a much more efficient way to heat or reheat than your stove top, mainly because your stovetop wastes quite a fair amount of heat. Your microwave uses about 80 percent less energy than your stove for heating up relatively small amounts of food.
Even though your microwave uses a lot of electricity, it’s a small burst of power vs. the long, delayed energy used to heat up your stove. Of course, you can save some of the energy you’re using on your stove by using pots that are size appropriate to the burner. The EPA warns that using a six inch pot on an eight inch burner can waste the majority of the burner’s heat.
You can heat up a cup of ice cold water to boiling in an 800-watt microwave in 2.5 minutes. To find out how much energy that would take, you calculate the amount of electricity used in kilowatt hours (kWh) by taking the device’s wattage and multiplying it by the time. So 2.5 minutes = 0.042 hours, and 800 watts is .8 kW. Multiplying kWh capacity by time, we get .8(0.042) = .034 kWh to heat the cup of water.
So, when you want a great reason to do dinner the easy way and need some scientific numbers to back it up, refer back to this blog and pop that plate in the microwave - to save money of course.
Check out our substainability page for more energy saving tips.