What are some tips for energy efficiency when cooking?

Question

Are appliances made of certain materials better at conducting heat in different situations? Does using lids really work?

Answer 1

Here are some general tips on how to maximise energy efficiency when cooking:

• Make sure that the size of the pan and the size of the induction element (for electric stoves) are the same. According to the US study SmarterHouse, cooking with a 6-inch pan on an 8-inch ring will waste over 40% of the heat energy produced.
• Use different materials depending on the cooking method. Copper pans heat up faster than normal pans on the stove, but glass and ceramic trays cook better in the oven. For pans, make sure they have a flat bottom to maximise the surface area in contact with the hob.
• Avoid placing foil on the racks in the oven. It disrupts circulating air, slowing the convection cycle, as well as producing waste.
• Keep the oven door closed as much as possible. Uswitch state that temperatures can drop by as much as 25 degrees when the oven door is opened during use.
• Cook with a lid on the pan – according to a study cited by Ben Morelli, this cuts energy use eight-fold. It also helps to keep moisture in, reducing water usage if you otherwise add boiling water/stock to prevent food from drying out.
• The same study also recommends cooking food in larger batches. It found that heating is more efficient when there is a greater volume of food, and so a pot only one-fifth full has a reduced energy efficiency of 80%.
• Only use as much water in a pan as you need to cover the food in it. Extra water just requires excess energy usage and will end up evaporating anyway.
• Cut food up to make it cook quicker, or parboil food such as potatoes before cooking it in the oven (to reduce roasting times).
• When using a steamer, use multiple levels of steaming baskets to maximise the energy usage of a single hob. An example of this would be boiling potatoes and peas in a pan, whilst steaming carrots and broccoli on top.
• Keep pans and ovens clean, so that less heat is absorbed and wasted, rather than being transferred to the food you are cooking.

For advice on the energy efficiency of different modes of cooking, see “What Is the Most Energy Efficient Mode of Cooking Food?” (OneSharedEarth, April 2020).

Bibliography

American Council for an Energy-Efficient Economy, 'Energy Saving Tips', SmarterHouse (2015), accessed at: https://smarterhouse.org/cooking/energy-saving-tips

Morelli, B., 'How cooking method and practise affects energy consumption', Yale Environment Review (14 January 2014), accessed at: https://environment-review.yale.edu/how-cooking-method-and-practice-affects-energy-consumption-0

Uswitch, 'Energy-efficient cooking', Uswitch (2020), accessed at: https://www.uswitch.com/energy-saving/guides/energy-efficient-cooking/

Answer 2

Some tips to add to the list:

• Let frozen items defrost naturally in the fridge overnight to cut down on energy spent in defrosting or cooking them from frozen.
• Use pots and pans which are the right size - not too big - for the amount of food you are cooking.
• Don't place the pot or pan on a heating element that is too large for it - this will result in heat being wasted. The same applies if the gas flame is licking on the side of the pot or pan.
• Know your cooking rhythm. Perhaps having everything ready to cook, rather than looking for items or chopping vegetables during the cooking, will save the amount of time the appliance is switched on for. Or maybe, go over the recipe and plan which tasks can be done while cooking and which need preparing in advance.
• Preheating the oven may not be necessary for all types of cooking.
• Whether using the oven or the stove, try turning the heat off before the end of cooking time. The oven or pot will retain the heat and allow the food to cook. You'll have to experiment how much in advance you can turn the heat off for a recipe.
• Soaking grains like barley, rice, lentils and chickpeas can reduce the cooking time. Some grains can be soaked overnight.
• Packing the oven so multiple items are cooked simultaneously can reduce oven use, and hence energy use.
• Letting the leftovers cool before placing them in the fridge helps the refrigerator work less hard to cool them down, hence saving energy.

References

Bloch M, “12 Tips for Conserving Energy When Cooking” (Green Living Tips, April 2011)

Escudero E, “4 Tips to Prevent a Thanksgiving Energy Bill Spike” (Energy.gov, November 2016)

Saines K, “Chef Reveals Energy Saving Cooking Tricks” (The Money Pages, September 2018)

Turlip P, “Cooking Up Some Energy Saving Tips” (Energy.gov, 2014)