This air cooling system for the slums uses plastic bottles and requires no electricity

In Bangladesh, 70% of the population live without regular electricity, often in tin-sided huts which can reach 45°C inside.

This simple solution is made from recycled materials and can cool a room by 5 degrees, making life much more bearable.

It works by the same underlying physics as a refrigerator, where pushing a gas through a small hole causes a cooling effect once the gas expands again on the other side. You can experience this yourself too. If you breathe onto your hand, you’ll feel the air movement as quite warm since it was heated to your body temperature. But if you purse your lips together and blow in a smaller stream, the air feels cooler.

This is how the Eco-Cooler works. Check out the video above for a full insight.

Developed as a collaboration between the advertising house Grey and local Grameen Intel Social Business Ltd (formed as a joint collaboration between Intel Corporation and Grameen Trust, who provide IT solutions for rural entrepreneurs who provide a service using computing technology in their local communities), they set out to find a solution to the overbearing heat a lot of people lived in, while being simple enough for people to produce and benefit from themselves.

By drilling holes in a board and cutting plastic bottles (which themselves are widely available for free as a litter problem) into funnels for the air, the solution and design are simple enough that 25,000 homes have already been able to implement it.

An excellent example of a simple innovation which just focuses on a solution to a problem, without being overengineered.

It just goes to show that often, you don’t need extremely complex and expensive infrastructure projects to bring benefits to hundreds of thousands of people. As long as they provide a real benefit, simple solutions can work wonders as well.