Most American main course recipes recommend use of a conventional oven. Yet most of the energy used by your oven goes to heating up the air inside the oven and around it. Conventional ovens tend to be large and take a long time to get hot, and they are not the most efficient way of cooking.
Ovens have a temperature control and a thermostat. When you set the temperature, the oven operates at full power for as long as it takes to get about ten degrees hotter than the temperature you set. Many ovens have an indicator that lights up when the heating element is on. So the most energy is used when you turn the oven on and the elements are running continuously.
Once the oven is at the desired temperature it takes less energy to maintain. Here are some ways to use the least amount of energy when cooking with an oven.
- Have everything ready, or nearly ready if you are preheating, before turning on the oven.
- Only preheat when necessary, for baked goods. Starting with a hot oven also keeps grated potatoes white. Most casseroles and meats can be put in immediately, without reheating.
- Avoid opening the oven door, especially when the refrigerator door is open. Many chefs believe that opening the door dries out the food. Better to keep the door closed and skip the basting.
- Fill the oven to its full capacity. Even better, make enough food to fill it up a second or third time. Aim to combine a few days or a week of baking into one long session. But baking uncovered meats and vegetables together may result in meats with a less crispy crust.
- Use baking pans that come with your oven, as they fit perfectly and maximize space.
- Use a thermometer to keep track of the oven’s temperature. Ovens are notoriously inaccurate.
- Experiment with turning the oven off five or ten minutes before the food is finished.
- Use a timer—and your nose—to avoid overcooking. Some ovens can be set to turn off automatically.
- You may not need to set the oven on low to keep food warm—many ovens retain enough heat to keep food hot for half an hour or more, as long as the oven door stays closed.
- Avoid using the oven in the summer, especially if you use air-conditioning. If you must, choose the coolest time of day and keep the kitchen well-ventilated.
- In the winter, open or close the kitchen door depending on where you want the house to be warmest. Leave the oven door open when you are finished, but keep small children away.
- Most casseroles, meats, and vegetables can be cooked in the microwave or on top of the stove.