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Culture Change print magazine issues: 20  19  18  17  16  15  14  13  12  11  10  9  8  index

Pedal Power solutions to petroleum dependence and polluting vehicles: Arcata Library Bikes, Pedal Power Produce, and more!

CAOE - Committee Against Oil Exploration - stop offshore oil drilling to protect sensitive habitats and cut petroleum dependence.

Culture Change through music! The Depavers eco-rock!

Take our Pledge for Climate Protection and learn about the Global Warming Crisis Council.

SEI hometown action!
Arcata city council's proclamation against war on Iraq and Kyoto Protocol proclamation.

Overpopulation has become a reality.  Overpopulation Resources and News Tidbits

Sail Transport Network

Fact Sheets
Press Releases

Long Distance


Tools for Sustainability


Lets us thrive in our neighborhoods and bioregions by managing our own lives, households and communities with freedom and respect. - Jan Lundberg

Please suggest articles and links, or send your own articles with graphics to

Malcolm Wells' architecture is below ground, saving energy and space for life.


If you like kickstands... Manage your bike with a flipstand by Jim Doherty 

"People can organize and invest in their neighborhoods and regions."  Restructuring Our Economic System(s) by Mike Morin

Human liquid waste for food production

- - - - - - - - 

by R. Forrester



    The PROCESS-INTENSIVE AIR WELL (PAW) is a low-tech, easily improvised instance of a downhill gas-liquid countercurrent heat exchanger which can be used to harvest atmospheric moisture using primarily the cold provided by ground-chilled, non-potable well-water.  The PAW provides additional services as a low-energy air chiller, air dehumidifier, air filter and source of negatively ionized air.



    The PAW consists of commonly available items.  The exterior of the PAW is a vertical stack of 3' ID concrete sewer pipes some 8' tall.  The exterior resembles a short chimney which is open at the top and closed at the bottom.  Inside of the concrete tube is a parallel vertical bundle of thin walled copper tubing with an ID of perhaps 0.200".  The individual tubes are not contiguous but almost so.  The tubes are uniformly distributed with a max clearance of perhaps .10" separating the tubes.

    A water pump causes cool well water to flow upward through the copper conduits.  At the same time, an air blower causes outside air to flow in the opposite (downward) direction through the air passages separating the tubes.  Countercurrent heat exchange warms the upward flowing water and chills the downward flowing air.  An electrically powered water chiller ensures that the well water entering the bottom of the concrete chimney is at least 5 degrees Fahrenheit below the dew-point of the outside air entering the open top of the chimney.  

    The downward drag of the air accelerates the migration rate of the condensate drops accumulating on the outside of the copper tubes to the water collecting cistern at the closed bottom of the concrete chimney.


    The cooled, dehumidified air exhausted by the system is ducted into the interior of an adjoining house to provide air conditioning.  Since the PAW provides two distinct services - the electric cost of harvesting freshwater from warm, moist air is thus cross amortized.


    The warmed well water is permitted to flow back into the well to be re-chilled by the cool earth underground.



    The PAW not only generates freshwater but also cools, dehumidifies and decontaminates air flowing through the PAW.  Soot and hygroscopic molecules such as SOX & NOX function as condensation nuclei.  Micron size soot ingested in a liquid is harmless but inhaled as an aerosol it is a major threat.  Conventional air conditioners generate positive ions which irritate the lungs.  Condensation droplet formation creates negatively ionized air which is rain-fresh.

    Notice that well over 90% of the cooling is provided by cool undeground water - not the auxiliary water chiller.  Hence this is not energy-intensive air cooling.



    Arguably, a modified PAW could be used to clean up coal fired power-plant emissions.  Electrostatic precipitators cannot capture micro-soot.  And crushed limestone is an expensive way of de-acidifying emissions.


    Reflect:  coal-fired power-plant emissions are rich in valuable fullerenes (a family of molecules with industrial potential).  Moreover nitric and sulphuric acid are the most important industrial acids.  The absolute humidity of coal flue gases tends to be high,  facilitating condensation.  The sour, sooty and fullerene-rich condensate would not be waste but feedstock for the chemical, activated carbon filter and materials industry.  Recall that gasoline was once discarded as a waste product of petroleum distillation.  Given PAW scrubbers  -  down-and-dirty coal burners fueled with cheap high sulphur coal would be environmentally compatible -    besides being much cheaper to operate.  The PAW emissions suppression technology might even be self-supporting.



    Assuming an average water harvesting rate of 5 ml of water per cubic meter of air and an airflow of 3 cubic meters of air per second - a given PAW might generate 1295 liters of freshwater in 24 hours.  If 100 liters of freshwater defines the minimum of freshwater per person per day compatible with a minimal acceptable standard of living  -  one PAW might provide for the water needs of perhaps a dozen individuals.



    Places with toxic, brackish or contaminated well water.  The arsenic-contaminated tube-wells of Bangladesh & India & central Asia come to mind.  Also the uranium tailing runoff polluted wells of the 4-corners region.  Not to mention hyper-mineralized CAP water challenged Tucson. Obviously, the Middle East and the freshwater starved tourist islands of the Mediterranean come to mind as well.


    Notice that well water is recirculated and not consumed.  This is important in the context of PAW deployment in dry regions such as the 4-corners area.  Not to mention subsidence-threatened Tucson sitting on top of its fossil water aquifer.  



    I will send sketches of the construct to anyone who asks for them provided the request is accompanied by a stamped, self-addressed envelope.  I intend to put the construct in the public domain.  I am not interested in patenting the concept or profiting from it. 


    My address is:    R.  Forrester

                               402 Adams Drive

                               Mt. Shasta City

                               California, 96067  


Human liquid waste for food production

Workshops on a range of systems (urine-div, site-built, eco-resort, microflush, graywater) will take place in Baja California Sur and Port Townsend, Wash. in November, 2004.  Contact via email to inquire or register for future programs
Liquid Gold: How to Use Urine to Grow Plants (Safely!) 
A talk, mini-workshop and book release were given on July 10, 2004 in Berkeley, Calif.   
Proceeds of entrance fee helped fund City Slicker Farm's urban farming demo programs.   
The urine-resource  presentations were led by Carol Steinfeld and Nik Bertulis   

Every day, we urinate nutrients that can fertilize plants that could be used for beautiful landscapes, food, fuel, and fiber. Instead, these nutrients are flushed away, either to be treated at high cost or discharged to waters where they overfertilize and choke off aquatic life.  [The workshop was a] lighthearted but practical talk about how urineówhich contains most of the nutrients in domestic wastewater and usually carries no disease riskócan be utilized as a resource. [discussed were] three ways to grow away urineócomposting, urine-graywater system, and urine fertilizingósafely and without odors. [Participants made] a small urine-graywater planter and look at ways to make easy, inexpensive urine-diverting composting toilets.

Discounts [were made] available on urine diverters, dry urinals, and copies of Liquid Gold, as well as related books and plans.   Our setting [was] Green Fairy Farm, a micro-eden in Berkeley. Due to limited space, registration [was] limited.     

The book, Liquid Gold (, shows how urine is used worldwide to grow food and landscapes, while protecting the environment, saving its users the cost of fertilizer, and reconnecting people to the land and the nutrient cycles that sustain them. Thatís real flower power! Liquid Gold features three ways to use urine hygienically and productively for plant growth, with studies that show the science behind this practice. Several advocates of urine diversion and their gardens are profiled, demonstrating that using urine for fertilizer is a feasible, safe, and cost-saving way to prevent pollution and save on fertilizer costs.    

Presenters: Liquid Gold author Carol Steinfeld is projects director for Ecowater Projects, a nonprofit project that informs the public about ecological wastewater management solutions. She is the co-author of The Composting Toilet System Book and Reusing the Resource: Adventures in Ecological Wastewater Recycling.  Her articles have appeared in Natural Home Magazine, Mother Earth News, and Biocycle, among others.     Nik Bertulis is a world-roaming carpenter, inventor, activist, and ecological solutions advocate, who also assists at City Slicker Farm and Green Fairy Farm.   Register:   

--   Liquid Gold   The Lore and Logic of Using Urine to Grow Plants   a book




Articles of interest:
Measuring and controlling the actions of governments 

Anti-globalization protest grows, with tangible results. 
WTO protests page

Tax fossil-fuel energy easily
by Peter Salonius 

UK leader calls War on Terror "bogus"

Argentina bleeds toward healing by Raul Riutor

The oil industry has plans for you: blow-back by Jan Lundberg

It's not a war for oil? by Adam Khan

How to create a pedestrian mall by Michelle Wallar

The Cuban bike revolution

How GM destroyed the U.S. rail system excerpts from the film "Taken for a Ride".

"Iraqi oil not enough for US: Last days of America?"

Depaving the world by Richard Register

Roadkill: Driving animals to their graves by Mark Matthew Braunstein

The Hydrogen fuel cell technofix: Spencer Abraham's hydrogen dream.


Ancient Forest Protection in Northern California. Forest defenders climb trees to save them.

Daniel Quinn's thoughts on this website.

A case study in unsustainable development is the ongoing crisis in Palestine and Israel.

Renewable and alternative energy information.

Conserving energy at home (Calif. Title 24)

Culture Change/Sustainable Energy Institute mailing address: P.O. Box 3387 , Santa Cruz , California 95063 USA
  Telephone 1-215-243-3144 (and fax)

Culture Change (Trademarked) is published by Sustainable Energy Institute (formerly Fossil Fuels Policy Action), a nonprofit, 501(c)(3) California non-stock corporation. Contributions are tax-deductible.