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Chilled the smart way with the electricity-free refrigerator

Sustainable alternatives for private users

A smart refrigerator? In the age of smart technology, being “innovative” doesn’t automatically mean that your watch can now make you breakfast, or that your kitchen appliances will start engaging in philosophical discussions with you. But what it does mean is that entrepreneurs are doing their bit to counteract the growing energy requirements for appliances in industrial nations. With her start-up company Coolar, Julia Römer and her team from Berlin are doing exactly that.

By developing a refrigerator that is environmentally-friendly, affordable, and non-power reliant, Coolar is doing more than just creating sustainable options for private users in our part of the world; it is opening up prospects for the just under 1.4 billion people who have to get by without any electricity. In these poorer parts of the world, people don’t associate electricity with luxury items like televisions or games consoles; they see it as a way of keeping vital medication chilled or storing food, to name just a couple of examples. All the Coolar refrigerator needs to operate is sunlight and water.

A vacuum and silica gel as main operating components

We’ve all seen the tiny bags which come with fragile deliveries such as your new laptop and are meant to absorb the moisture from the surrounding atmosphere. Their filling, called silica gel, happens to be an important part of the Coolar’s refrigerator concept as the appliance is powered to a large extent by the absorption effect in a vacuum system.

In short, low system pressure means water evaporates at the ambient temperature. This evaporation process draws energy from the surrounding atmosphere in the form of heat – thereby cooling the surrounding space. This evaporation cooling effect is accelerated by the fact that the silica gel downstream absorbs the vapour. This frees up increasingly more space for further evaporation, allowing a larger quantity of distilled water in the system to evaporate.

Find out more about this start-up company in the following video.

Source: Coolar Tech/ YouTube

Solar heat as a source of energy

This is only possible as long as the silica gel has sufficient capacity to absorb the water vapour. If the maximum capacity is reached, the material must be dried using outside heat (around 60°C) in order to regenerate the absorption capacity and repeat the process described. This thermal energy should ideally come from solar heat systems or from other CO2-neutral sources, such as waste heat.

A quieter and more environmentally-friendly refrigerator

Generally speaking, the evaporation and drying processes are sound-free. So you would no longer hear the humming noise your refrigerator makes every now and again. Toxic and environmentally-harmful coolants and lubricants become equally redundant. As a result, the electricity-free refrigerator doesn’t have to be disposed of as hazardous waste – if it has to be exchanged at all – since the absence of movable, wearing micro-parts makes the appliance last considerably longer. An alternative living concept, which focuses entirely on sustainable living, is the Earthship.

The Venture: The first step towards international success

Barely a year and a half after company founder Julia Römer and her team started out on their journey, Coolar’s innovative concept caused something of a stir. The start of 2016 saw the company’s co-founder Arno Zimmermann profiled in the “Social Entrepreneurs” category of the 30 Under 30 list in the European edition of the renowned business publication Forbes Magazine.

In the international finale of the social start-up competition “The Venture”, Julia Römer demonstrated yet again the standard of ground-breaking sustainable technology from Germany. While the jury – made up of prominent personalities including actress Eva Longoria – chose Oscar Mendez and his pitch on “Conceptos Plásticos”, Ms Römer still received $50,000 to put towards continued use. The company founder now intends to rapidly invest the capital into making advanced prototypes. In doing so, she hopes to convince new investors of the viability of her innovation.

The electricity-free refrigerator is particularly interesting for home owners with solar heat systems. What do you think of the idea?

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