A man in Bangladesh has apparently invented a cheap air conditioner that works without electricity. It is intended for the many places in the world where electricity is expensive or too scarce to waste on cooling, but would work amazingly well in any of your off-grid projects.
It’s a simple system too. It works on the principle that when you take air and force it to compress, it loses a great deal of heat. This principle can be shown by your mouth. When you just open your mouth and breathe out, the air is hot. However, when you purse your lips and blow, the air is cooler. This system works the same way.
Here’s how it works:
Take a board and cut it to the same size as the window you’re going to place it in. Drill holes in a grid pattern across the entire board, and make them just large enough to fit the necks of bottles through. Cut the body of the bottles, so you have a funnel shape, and discard the remainder of the bottles. Fit the necks of those bottles into the holes on the board, and put the board up in your window.
What happens at this point is that when wind blows towards those funnels, it is compressed and forced through the necks of the bottles into the house, and the resulting air is as much as 5 degrees Celcius cooler than it was outside. This could make a huge difference on those sweltering days.
The actual plans for this will be available, for free, on Eco-Cooler.com in the near future.