In the Middle East the concept of a cooling tower has been used for centuries to provide cooling for homes, food, and water. Below is a diagram depicting how a wind tower is used to create a high/low pressure system to draw cooled air into the building and expel hot air. Another method of creating a draft is a solar chimney, which is simply a chimney painted black. It utilizes the heat of the sun to heat the air inside the chimney (hot air rises) resulting in a natural draft.