Microwaves vs. Ovens: What's the Greenest Way to Heat Your Food?
You might have several appliances available in your kitchen that can cook, but which one you choose—and how you use it—can have a significant impact on your energy consumption. Here are some general tips for getting the most out of your appliances and a relatively easy way to figure out which appliance would use the least amount of energy to cook your food.
Stovetops: With an electric stovetop, make sure your pan completely covers the heating element. With gas burners, make sure the flame is fully below the pan; otherwise, you’re paying to heat the air around the pan, not just the pan itself. Also, use the appropriate size pan for your meal. Smaller pans are easier to heat up.
Keep appliances clean. Clean surfaces maximize the amount of energy reflected toward your food. This applies to microwaves, toasters, ovens and other appliances.Keep a lid on it! Covered pots retain heat and help cook food more quickly.
Take advantage of residual heat. Turn off the oven or electric stovetop several minutes before the recipe indicates. Both will stay hot enough to complete the cooking process.
Don’t preheat the oven unless a recipe requires it.
Use the right cookware. Glass and ceramic cookware conducts and retains heat better than metal. If a recipe calls for a metal baking pan, switching to glass or ceramic allows you to lower the oven temperature by 25 degrees.
Don’t peek. Opening the oven door can lower the internal temperature as much as 25 degrees. Use a timer to set the cooking time, and be sure your oven window is clean enough for you to see how your dish is progressing.
Energy Hawk has even more tips for saving energy and gas in the kitchen and elsewhere.
To figure out which appliances use the least amount of energy to heat your food, check their labels for average wattage. Multiply the wattage by how many hours or fractions of an hour you need to cook the food.
For instance, cooking something in a 900-watt microwave for five minutes (1/12 of an hour) uses 75 watt-hours of energy. If you have gas appliances, their energy consumption is measured in British thermal units, or Btus. One Btu is equal to approximately 0.293 watt-hours.
If you’re feeling handy, you might want to take advantage of all the free energy pouring out of the sun with your own solar cooker. Some solar cookers can even be made out of recycled material around your house. The major drawback is that cooking times are often longer for solar cookers than with appliances.