Listen to mama.

“As your mother always told you, don't leave the refrigerator door open. Every time it's opened, up to 30 percent of the cooled air can escape. The same rule holds for the oven, too. “

https://www.powerhousetv.com/EnergyEfficientLiving/EnergySavingTips/101WaysToSaveEnergy?utm_source=WS&utm_campaign=Energy-EfficientLiving/Energy-savingsTips/027471