Introduction

2004 has been a relatively quiet year for S.T.E.V.E.N. Foundation. Most of our technologies for solar energy and other aspects of sustainable energy development remained in their previous state—including our solar collectors, tracker, water pumps, steam engines, and solar oven.

At the same time, several significant activities deserve to be reported. Please read on for reports on our educational outreach, solar ovens, wind energy, solar icemaker, and support of sustainable forestry. We will also remind you of instructional and actual construction materials we can offer to anyone working with our or similar devices. Best wishes to all!

Collaboration with Cornell “Engineers for a Sustainable World” on parametric testing of solar oven design

Since the 2003 newsletter, the national organization Engineers without Frontiers has renamed itself Engineers for a Sustainable World, and at Cornell we have both the offices of the national ESW organization and a course taught in Civil & Environmental Engineering in which students carry out projects that fit the mission of ESW. This year we teamed up with ESW on a parametric testing project for our solar oven design, which means a side-by-side test of two identical ovens in which one parameter on one of the ovens is changed (e.g. amount of insulation, type of reflective material, etc), so as to test the effect of that component on overall oven performance (see picture).

Two teams of students have carried out tests, one in the spring and one in the fall. The students were fortunate to have access to one of the labs in the engineering school that had a good southern exposure and also thermocouples and computers that could be used to automatically log temperature data during a run of the solar oven. So far there is an interim report on the STEVEN website from the work in the spring, although as of this writing the final results are still being compiled before producing a final report. We hope to have more to report next year. Many thanks to the students, and to Prof. Rachel Davidson and Mr. Tim Bond from C&EE, for their support for this project.

Photo of solar oven parametric test

Lecturing opportunities in the engineering college at Cornell

Francis Vanek lectured on three occasions on appropriate technology to Cornell engineering students during 2004. The first lecture was in the spring to the Engineers for a Sustainable World class, on general principles of the STEVEN approach to appropriate technology. This lecture was repeated in the fall semester version of the ESW class. In addition, the mechanical engineering design class chose as a term project topic the design of a low-cost water pumping system in Mexico, so Francis was invited to give an introductory lecture on appropriate technology to these students. We believe that the popularity of these lectures reflects an interest among engineering students from a wide range of disciplines in applying technology to developing countries.

The 2004 Windmill Story

In our last year’s newsletter we reported on our work in progress on a low-cost large windmill. Unfortunately the project had to be abandoned. Our initial hope was that we could deal with possibilities of strong wind through a system whereby the blades of our four-arm mill could align automatically to the wind direction in case of very strong wind, and thus prevent harm resulting from the strong wind.

Nonetheless, a strong wind of some forty MPH velocity destroyed the rotor for a simple reason: the blades could theoretically align to a strong wind. However, strong winds are never perfectly directional--they vary in direction through bluffs of various strength and directions. This caused strong impacts on the blades even if they were aligned in the main direction of the wind. One blade thus ultimately distorted and destroyed the rotor, constructed by design of light materials. The conclusion is that low-cost windmills of larger dimensions can never be durable and practical.

Large-size rotors like those developed in Denmark and now being installed in various places in the United States, of some 300’ total height, require both a very sturdy and costly design and a complex mechanism protecting the mill against high velocity winds.

For our part, this going from enthusiasm to negation about low-cost windmills should not be interpreted as our loss of interest in wind power, in which we still believe as a viable sustainable technology. But within our limited means at STEVEN Foundation, we want to concentrate on other technologies.

New 2004 Solar Refrigerator

Over the years we have received many inquiries about our solar refrigerator reported on in HOME POWER, June 1996. That design, based on an intermittent ammonia cycle using calcium chloride, while it worked, turned out to be rather impractical.

The ammonia generator calls for a stable horizontal boiler heated through a horizontal east-west parabolic collector [see the article]. But this precludes the possibility of tracking and thus sacrifices considerable solar heat. To capture this heat loss and benefit from direct insolation with high energy efficiency, we are now working on a similar refrigerator with horizontal boiler and parabolic collector where the collector and the entire refrigeration unit are mounted on a rotating platform which permits of one hundred percent insolation.

Most of the parts have now been completed, but the refrigerator could not yet be tested because the parts were not assembled, and especially because we do not have yet the ammonia gas to charge the refrigerator. Another new element of the refrigerator is a cooling-storage tank for generated ammonia before it is injected into the evaporation unit inside the ice-producing chamber.

The tracking/rotating structure with the parabolic collector frame are shown in the picture below. Ultimately the other parts of the refrigerator, the storage tank and the ice-chamber will also be mounted on the same platform, which can rotate on a fixed pivot and two small wheelbarrow-type wheels traveling in circles around the pivot.

Photo of parabolic collector frame

Sustainable Forestation Project: End of the Story

Working in Bolivia in the late 1990’s, Steven Vanek engaged with people there in a project for afforestation of a needy zone of that country. Returning to USA, he appealed through STEVEN Foundation for financial support of this effort, and was able to raise well over $400. The plan was to disburse the moneys to the Bolivian leader on his next visit there. However, Steven found that his Bolivian partner had moved on to other work. For several years we have been searching for a way to put this money to proper use in the developing world.

An opportunity in Haiti seemed suitable: thus we have responded to an appeal from the “Haiti Reborn” project of the Quixote Center, an NGO largely concerned with social justice issues, based in Maryland, USA. Haiti, as readers may know, is the poorest country in the western hemisphere: a tremendous need is forestation to counteract the felling of trees for charcoal, the customary cooking fuel throughout the country. Haiti Reborn has for several years been promoting the planting of trees in the region of Gros Morne in northern Haiti. In spite of the political turbulence of recent years, this project appears well run and able to succeed.

Thus in August the STEVEN Foundation supported Haiti Reborn with a contribution of $450. targeted for forestation in Gros Morne. We have been duly thanked for our gift and trust it will be put to good use. Renewed thanks to all who donated for sustainable forestry, years back.

[Additional note: from our perspective at STEVEN Foundation, a good alternative to cooking on charcoal in a climate like Haiti’s would be solar box ovens. We demonstrated the use of such ovens when visiting Haiti in January 1996: Steven Vanek returned later that year to teach the construction of the family-sized oven in a community in northern Haiti. We learned two lessons: 1] old cultural habits (i.e. the use of charcoal) die hard, and 2] Steven’s crew made a group of ovens, but people simply did not have the money to buy them.]

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Materials available: Besides the 1997 prospectus on various technologies, STEVEN Foundation offers manuals on: solar collector, tracker, water pumps, steam engines, solar box oven (English or Spanish), and explanatory material/consultation on icemakers. Our videos on “STEVEN Technologies” (1987) and “Building an Icemaker” (1995) are still available. Also, we have a supply of mirrorized mylar plastic as used in our collectors and ovens, which could help anyone doing a modest-sized project: please consult us for your needs.

Donations appreciated: STEVEN Foundation is a registered (501)(c)(3) non-profit. Your tax-free donations help our research toward a more sustainable world. Thank you!

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Final footnote: a reflection on the US presidential election just completed. Although it was difficult to follow a campaign in which environmental issues, which are so important to us at STEVEN, seemed to get relatively little attention, we encourage our readers not to lose heart. First, it is worthwhile to continue to press for stronger action at the political level on these issues. Moreover, we need to push forward outside the political arena, whether in the private sector or on a grassroots level. We hope that during 2005 you will join us in continuing to fight the good fight.