Improving Solar Distillation, Part 1

A typical DIY solar still. (Image from LSU Ag Center)

In this type of solar still, salt water is put in a sealed box with an angled glass top. As sunlight entering the box heats up the water, it evaporates into fresh water, condenses on the glass top and runs down into a collector.

Dr. Larry Winiarski pointed out that traditional solar stills, as above, have problems:

• Sealing water inside a box results in almost immediate saturation of the air.  

• Until the water vapor is condensed, distillation cannot continue to occur.  

• In a classic still, the glass condensing surface is warm. Effective condensers are supposed to be cold.

To improve production, Larry moved the hot, humid air (EVAPORATION) to a cold surface (CONDENSATION).

He used a chimney to pull air through the system.

In the next post, we’ll check out his most successful design.