We use an energy efficient refrigerator during the summer months. It has a freezer as well and only uses 60W of power. In the winter we unplug the fridge and store our refrigerated food in bins in the basement. We use our infrared thermometer gun to check the temperature of the basement. Once it is consistently below 40 degrees F we unplug the refrigerator and move our food downstairs. We place a cooler in a snowbank in the shade after the bears are hibernating to store frozen food during the winter months.
We usually preserve food by dehydrating it so that it's shelf stable and doesn't require electricity for storing (like with freezing). This can be done with a non-electric screen drying method or by using an electric dehydrator. We store dehydrated goods in jars in our pantry. Canning is a great way to preserve foods, but we didn't experiment much with that because of the long cooking time it requires during the hottest time of the year.