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Primitive ideas of ancient peoples by today’s means were not that primitive after all. For instance these ideas allowed for desert people to have ice during summer when there was no ice for thousands of kilometers around. Yakhchal is one such idea.
Although it looks like a new invention idea of a solar-powered refrigerator is relatively old and pretty simple - to use heat of the sun instead of the compressor in the refrigerator to liquefy the refrigerant. Read more about solar-powered refrigerators.
Fridges and their stronger and colder cousins - freezers are today required equipment in every home. But it was not always like that. They ancestors were much simpler and not too practical. Find out more about fridges history.
Refrigeration is one of the main food storage techniques in developed countries. But it was not always so. To keep our food cool we had to harvest ice from the nature itself. Today almost every household has a refrigerator. Read about refrigerator history.