A new do-it-yourself air-conditioning system relying on plastic bottles and wind is being used in Bangladesh and Pakistan to help cool homes.
The system, called Eco-Cooler, consists of cutting plastic bottles in half and mounting them on a board. The board is then placed on a window with the wider part of the bottles facing out. Hot air rushes into each bottle where it expands, thereby cooling the air before it enters the room.
The cooler’s efficiency varies based on conditions however, inventors claim it has the ability to reduce indoor temperatures by as much as by 5 degrees Celsius. Grey Group, an advertising consultancy, has already installed 25,000 Eco-Coolers across Bangladesh.