A new type of solar still has been developed that is cheaper and incredibly more effective than previous versions.
Though the concept of the solar still has been around for hundreds, if not thousands of years, the materials involved call for the process to be either slow or expensive. Up until now, a still that makes enough water for one person per day would have to be six square meters in size.
The common design is a simple black-bottomed vessels filled with water, and topped with clear glass or plastic. The black bottom heats up the water while collecting sunlight and the evaporated water is caught along the clear plastic, where it is deposited into a drinking container.
The problem is that it takes a long time and a lot of lost energy to heat the entire basin of water.
The new technique uses paper to wick the water, soak it up and evaporate it in small doses, proving 4x more effective, cleaning one liter of water per hour with only a one square meter basin.
The system allows people to collect water "much like they generate their own power via solar panels on their house roof,” says Zhejun Liu, a visiting scholar at the State University of New York (SUNY) in Buffalo and one of the study’s co-authors.
Floating blocks of polystyrene with paper, blackened with carbon black (a cheap powder left over after the incomplete combustion of oil or tar), the entire still can be constructed for $1.60 per square meter, as opposed to other more expensive versions that can cost up to $200 per square meter!
The ease of construction and immense value make this ideal for anywhere in the world that needs fresh water now.