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Phase Change Material Keeps Milk Cold When the Power Cuts Out

Illustration for article titled Phase Change Material Keeps Milk Cold When the Power Cuts Out

In rural Indian dairy villages, access to electricity is intermittent. Most people have to boil milk before they drink it, and dairy farmers face the perpetual risk of losing large batches of their product. Now Promethean Power’s new thermal battery tech offers a fascinating solution.


As Doc North explains in the video, milk can be chilled to maintain its quality without electricity, by using simple principles of heat exchange.

If using science to solve real-world problems gets you jazzed, you should check out some of Doc North’s other videos, too—he’s currently traveling across India, showcasing technologies and ideas that are changing people’s lives in awesome ways. [In The Making.]


Top image via Andrew Magill / Flickr

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So it still requires electricity; it is just able to maintain cooling during power outages, which are frequent in India. When the power is on, electricity runs refrigerators, cooling the milk and phase change material. When the power is off, the the phase change material takes over cooling until the power comes back on, hopefully before the material runs out of capacity.