S.T.E.V.E.N.

Sustainable Technology and Energy for Vital Economic Needs

414 Triphammer Road, Ithaca, NY 14850 USA.  Email jv19@cornell.edu.

Website: http://www.virtualithaca.com/francis/stevenhomepage.html

 

NEWSLETTER 2006

 

 

STEVEN  FOUNDATION  WORK  IN  2006

 

This year most of our technical work consisted in our return to the STEVEN low-cost Solar House, conceived of some ten years ago in conjunction with our consulting mission to Ghana, and in particular inspired by a flight from Geneva to Accra over the enormous expanse of the Sahara.  We have also continued to work with the Engineers for a Sustainable World organization at Cornell, and to respond to inquiries about the STEVEN technologies.

 

THE STEVEN SOLAR HOUSE AND ITS POSSIBLE APPLICATION

 

The STEVEN solar house is a structure that combines lodging with solar energy generation.  A concrete description and analysis of such a solar house, combining simple and inexpensive modern technologies with traditional/millennial concepts of the near-equatorial tents and pagodas, is given in Chapter 23 of Jaroslav’s UNIFIED THEORY OF SOCIAL SYSTEMS.  This book can be accessed online at the following URL: http://hdl.handle.net/1813/642

 

The essential idea, besides low-cost work and materials, is the realization of multiple externalities.  Specifically, the house energy is supplied by a simple solar collector with five simultaneous functions: 1. roof of the house; 2. a collector of solar energy for mechanical power, refrigeration, and heat provision; 3. a collector of water during periods of rain; 4. a permanent cooling effect because the inner house is always shaded by  the parabolic roof which transforms the solar heat into other forms of energy; and 5. the water collection also provides for automatic washing of the reflective area.

 

As is shown in the book chapter referred to above, the mechanical power of the house comes from a simple steam engine.  At the time of the first conception and testing, that engine was expected to consist of a simple low-pressure construction using off-the-shelf or recycled pipes, ball bearings, et cetera.  Later exploration has shown that such engines tend to be not very durable, and rather inefficient.

 

 


A NEW STEAM ENGINE DESIGN

 

The main endeavor of this year was to seek a more efficient and inexpensive form of transformation of solar heat into mechanical power. Of course, this could be done using photovoltaic panels, but these are rather expensive and they would dispose of the multiple-purpose of the parabolic roof collector.  Efficient thermal engines are turbines but to be efficient, they must be large as in power stations, and use high pressures. Neither attribute can be fulfilled with a relatively small and simple solar house.

 

But there is another solution, which was the focus of our work in 2006: transformation of a small internal combustion engine into a steam engine.  Specifically, we turn a roughly three horsepower four-stroke internal combustion engine into a double two-stroke steam engine. Thousands if not millions of discarded rotary lawnmowers could be used, eliminating all the carburetor and electric ignition components and keeping the rest of the engine, adapting the timing mechanism of the motor.  The prototype model of such a transformation runs extremely well, can be used with relatively high steam pressures, thus increasing the [Carnot] efficiency and durability of the motor.

 

In our work we used a discarded lawn-mower purchased at 20 dollars.  But such a new Briggs & Stratton motor can be bought in retail for below 200 dollars, and if the electrical and carburetor components are eliminated, on a large scale the cost could be reduced to some 50 dollars at most.  Indeed, the more primitive transformation that we have performed could be produced directly in the factory if thousands of such solar houses were to be built for sub-Saharan and Saharan developmental communities.  Alternatively, large numbers of obsolete lawnmowers could be collected through a philanthropic and ecological effort in the advanced economies of the super-Saharan world.

 

STEVEN work with ESW-Cornell chapter

 

STEVEN Foundation collaboration with the Engineers for a Sustainable World (ESW) Chapter and engineering course at Cornell has now entered its 4th year, with Francis Vanek taking an increased role in teaching and research related to this project.  Starting in August 2006, Francis has taken over as co-instructor of Civil & Environmental Engineering 492 “Engineers for a Sustainable World”, a three-credit service learning course in which students participate in one of four team service projects, ranging from water supply systems in rural Honduras to analysis of contaminants in the water at the southern end of Cayuga Lake (next to our home town of Ithaca, NY).  Francis’s role in the course is to serve as a faculty liaison to the projects, which are directly overseen by an advisor (typically a professional in the related field) and a contact from a community partner organization.  He also taught a number of the lectures for the lecture component of the course, which covered topics ranging from the history of solar energy to a discussion of the aftermath of Hurricane Katrina.  His co-instructor for the course is Prof. Park Doing of the Science and Technology Studies program at Cornell, who attended workshops of the STEVEN Foundation in the early 1990s while a graduate student at Cornell.

 

Francis had a close connection to one of the team service projects involving solar ovens.  This project is actually a continuation of a project for which STEVEN Foundation served as a community partner, during the 2004 Fall semester.  Since that time, ESW has developed a strong connection with “Grupo Fenix”, and NGO based at the National University of Nicaragua in Managua, and STEVEN has continued to maintain a connection with the project in an advisory role.  During the Fall 2006 semester, the students took the name “Amanecer”, meaning “sunrise”, for their group, and they worked on testing of a single-reflector design currently in use in Nicaragua, under the continuing supervision of Mr. Tim Bond, senior lab supervisor of the George Winter Laboratory at Cornell.  (See Bull & Hazeltine’s “Handbook of Appropriate Technology” for a description and construction plans for this particular oven design.)  An intriguing new development for this group is the creation of an artificial solar oven test bench that uses halogen lamps and floodlights to reproduce the effect of sunlight shining on an oven, so that students can now test ovens at any time of day and regardless of the weather.  We look forward to the continuing development of this testing facility and the collaboration of the students with their companieros in Nicaragua.

 

For information about the projects, lectures, and links to slideshows, interested readers can surf to http://eswserver.cee.cornell.edu/esw/.

 

STATUS OF OUR SOLAR ICEMAKER

 

We continue to receive inquiries about the STEVEN solar icemaker described in HOME POWER magazine 10 years ago, 6/1996.  We are pleased, and certainly agree that this is a promising and needed technology.  Intended improvements of the model are still on hold, since our lead technician, Steven Vanek, has been occupied elsewhere—currently, doing Ph.D. research on soil improvement in the Bolivian Andes, therefore spending a lot of time away from home base.  Let us hope that summer 2007 will provide time for progress on the icemaker project.  Those interested should communicate with us, to be kept updated.

 

REFLECTIVE MYLAR FILM STILL AVAILABLE

 

We have received several requests to purchase aluminized 3-M Mylar film from our excess supply.  Having filled one order, we could certainly handle more, if for a modest quantity—for example, for a solar box cooker, or one solar collector.  We are asking $1. per square foot of material, plus payment for shipping (typically about $4).

 

If interested, please contact: jv19@cornell.edu

            Or telephone:  607 257 7109

            Or write to the address on this newsletter.  Thank you!