So you would like to keep your food cool without using a refrigerator? The Groundfridge can help. It is a natural cooling system covered with a 1 meter thick layer of soil. It has a battery powered ventilator too. It uses the insulating capacity of the ground and cool night air temperatures to get the job done.
This cooler doesn’t need any electricity. It has 3000 liters capacity. You can find out more about it here.