ARC E-Newsletter 5/29/26: Improving Solar Distillation - Two-Stage Distillation
Aprovecho Research Center
Improving Solar Distillation: Two-Stage Distillation
In our recent post “Improving Solar Distillation, Part 1,” we talked about the traditional design for a solar still and pointed out some design weaknesses. Here we show Dr. Larry Winiarski’s suggested improvements to address those problems.
The distillation of brackish water is a two-stage process. Water is encouraged to evaporate and is then condensed. Sealing water inside an airtight vessel results in almost immediate saturation of the inside air. Until the water vapor is condensed, distillation cannot occur. As well, in a classic still, the condensing surface is warm and production of potable water occurs at a significantly reduced rate.
By transporting clean water vapor to a cool condensing surface, Dr. Winiarski addresses this problem. In his design with chimney, ambient air is warmed, improving its ability to absorb water vapor. Condensation then occurs underground, stripping the moving air of moisture. A large, cool surface area results in more effective condensation. A tall chimney acts as the engine, moving warmed air through the system. Air moving up the chimney is dry, after depositing the potable water into a receptacle.
New Webinar Series - Stove Design on June 11!
The team at Aprovecho Research Center is excited to launch a new webinar series. We are covering the areas that have the largest interest as indicated by a recent survey of Regional Testing & Knowledge Centers, from carbon finance to stove design. We hope you can join us live! The webinars will be recorded and posted on the Aprovecho.org website, but live participation is preferred if possible so you can ask questions.
Click each link below to RSVP and receive a calendar invitation in your local time zone.
Thursday, June 11th, 6am-7am am PST: Stove Design, Sam Bentson
This webinar curates current test results from new stove design work at Aprovecho on charcoal stoves, rocket stoves, and TLUDs and teaches how they are made.
https://www.addevent.com/event/bcc6t5pv6l7g
Thursday, July 2nd, 8am-9am PST: Emissions Testing, Travis Volpe
This webinar dives into Emissions Testing with an overview covering methods and equipment.
https://www.addevent.com/event/3lshl97kw1w0
VIEW NOW ON YOUTUBE: Carbon Financing, Dr. Nordica MacCarty
This webinar covers the basics of carbon financing, including how it works and the details of the sample sizes and measurement requirements of the new CLEAR methodology.
Carbon Financing: https://youtu.be/FbfieX-zeZQ?si=YnYsQ9brshOoFMDj
VIEW NOW ON YOUTUBE: Field Testing, Jaden Burger
This webinar provides an overview of the various field tests for cook stoves available, what they measure, and when to implement them.
Field Testing: https://www.youtube.com/watch?v=e5s3ZsitTY4
We look forward to seeing you there,
The Aprovecho Team
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