The S.T.E.V.E.N. Foundation Newsletter 2000

Solar Technology and Energy for Vital Economic Needs

S.T.E.V.E.N. Foundation,
Ithaca, New York, USA
Tel/Fax (607) 257 7109
Email jv19@cornell.edu, francisvanek@yahoo.com


Introduction

Dear reader, welcome to this year’s version of the annual STEVEN newsletter.  In this issue, the president’s report first gives an overview of the structural changes to the organization, and then the director discusses the current program of the foundation.  Thereafter, both latest progress with technologies and also with policy advocacy work are covered.  Last is an editorial comment from the Foundation about the state of affairs with appropriate technology today.  We hope you will enjoy this newsletter and welcome any comment you may have.

Included in this newsletter:
1. Overview of the Foundation
2. Solar Energy
3. Superbike technology
4. Outreach work
5. Editorial

REPORT BY THE FOUNDATION PRESIDENT
by Jaroslav Vanek

   In the time since our last annual newsletter, we have been keeping busy with a number of activities on quite a variety of fronts.  First to note is the change in our administrative structure. While J. and W. Vanek remain the members of the board of directors and the president and secretary of the Foundation, with departing Marc White [see last year’s newsletter], Francis Vanek becomes the director of the foundation activities until the summer of 2002, with possibility of renewal thereafter. The position remains -- as it has been to date with Jaroslav Vanek -- an honorific pro-bono position. However, Francis as PhD in systems engineering from the University of Pennsylvania may be called on to act as a technical advisor and principal research officer with corresponding remuneration. More about the future orientation of the Foundation will be said below by him.
   Along with our expansion of focus from solar technology to sustainable technology of last year, the arrival of Francis on board will allow us to further expand our activity to research and publication in the field of sustainable technology, even while continuing all the past work [see reports below].  A good deal of publication in this area was accomplished already, especially by Francis, who will now have the option of publishing his ongoing work under the auspices of the Foundation.

DIRECTOR’S PERSPECTIVE ON THE DIRECTION OF THE FOUNDATION
by Francis Vanek

   As the newly appointed director of the STEVEN Foundation, I would like to take this opportunity to describe where I see the Foundation going in the future.
   First, I see our work as continuing to promote appropriate technology, focusing our efforts on two key areas we have identified, namely solar ovens and superbike bicycle design.  In doing so we are recognizing that it is not possible for us to advance all the technology designs at once, given our available time.  However, we will continue to demonstrate and distribute information about other technologies, including hand pumping, parabolic solar collectors, steam engines and steam applications, and solar refrigeration, where possible improving existing designs and documentation.
   We remain open to the promotion of the technologies through "missions" into the field, especially to some of the developing countries.  Such missions were carried out recently in Bolivia, and further back in Mexico and Ghana, among other places.  Many recent missions were carried out by members of the Vanek family, and as we become more settled in our work in the U.S., we would do well to find individuals outside our family who can take our know-how into the field.  In the past a number of students came from Cornell to learn about the technologies from us while they were in Ithaca, and some of these went on to work in the developing world.  I plan to explore this connection to see whether once again students might visit us to see what we are doing.
   Along with the direct demonstration of the technologies by volunteers in the field, I am very interested in finding an effective way to make information available without a physical presence in the location where the technology will be put to use.  To this end, we will need to update and improve our documentation about the technologies.  We should also find other channels for spreading the word about our designs, such as the Appropriate Technology Sourcebook, where people can find out about our work, and if they are interested, write to us for construction manuals or other information.  Eventually this may lead to a comprehensive website where people can look at our designs and what they do, and then download construction manuals or other information.  Such a website is still some way off in the future, but it is certainly worth beginning to think about it at this point.
   Another new direction is toward policy analysis regarding both AT and ecological issues in both the industrialized and developing worlds.  This type of work will move us from thinking about the individual device to the context for such devices, including issues of demographics, cost, or possible benefits from building the devices.  Such analysis brings in Jaroslav’s background as an economist and my own as an operations researcher and systems analyst.  I will also be pursuing my work, outside of the STEVEN Foundation, in the field of transportation policy with regard to the environment.  This work will be carried out as part of a new entity which I have created, the Sustainable Technology and Energy Institute, although given the importance of the environment in both cases, there will clearly be much synergy between these two efforts.  The new Institute is a virtual entity only at this point with no office or physical building (as the reader will probably have guessed!), but it may grow into such an entity in the future.
   In conclusion, in my involvement with the Foundation over the years, I have come to see the value of staying with an organization for the long term.  I remember from my childhood the first experiment which eventually led to its formation: a large number of small bathroom mirrors focused on an egg in a frying pan in our front garden in a house we were renting in the Netherlands in 1980.  Gradually over the years we worked on a wide range of technologies and accumulated a great deal of experience.  Now that we have come this far, it is important at this point to go forward in disseminating this experience to others who are interested, while at the same time continuing to experiment and improve our designs, not just for my term as director but for many years beyond that.
 

SOLAR ENERGY

IMPROVED TRACKING MECHANISM

The essential component of our tracking mechanism is a single-metallic, two-angle aluminum sensor controlling a hydraulic crutch [see our prospectus]. Over time in years of testing we found its functioning somewhat imperfect because of the rather small differences in the length of the insolated versus the shaded angle amounting to a few hundredths of an inch. In order to make the sensor more reliable, we have introduced three alterations. First, we have doubled the length of the two angle aluminums in order to double the expansion impact on the valve allowing water
to flow from the hydraulic clutch and thus make the sensor more sensitive. Second, we have introduced a key-type simple adjustment mechanism which permits to set or reset exactly the position of the two angles to have the initial "closed" position of the sensor exactly at the "closed" position, so that even a small amount of insolation
starts opening the evacuation valve and moving the collector with the sun. Third, we now suspend the lengthened sensor in an easy attachable and rotating position so that the sensor can, if necessary, be aimed or not aimed at the sun. This third alteration is especially useful with the other major development discussed presently.

FINE TUNING OF TRACKER WITH AUTOMATIC RESETTING

We feel that our tracking mechanism, which is design primarily for simple hands-on, or "human-proximity" situations, is quite adequate for the purpose.  With a user of the tracking collector living near or at least coming near the collector once per day, it takes a few seconds to reset the tracker after day's operation for the next morning, and refill the hydraulic crutch with new water, perhaps no more than one quart for the days operation. However, in some cases it is desirable to have this resetting done automatically, AND still using only hydraulic principles based on water pressure, without use of electric sensors or electric mechanical devices.
   We find that this is possible using a new hydraulic automatic tracker, working as follows: First, the end of day's operation must be defined by the position of the sun and hence by the final position of the collector. At that point, say exactly at five o clock in the afternoon, the flow of water from the crutch is arrested by a device [valve or simply squeezing a water-duct] linked/related to the final position of the collector, at which point the collector stops progressing with the position of the sun. The same mechanical action which shut off the crutch's motion at the same opens a valve of water coming from an external pressurised source [such as a water faucet or a
reservoir at elevated position]; such water then is made to enter the hydraulic crutch, refilling it, and thus pushing the collector in the opposite direction until it reaches a preset position of tracking start, say at ten o clock in the morning. This position is preset by a given length of a cable which shuts off the valve bringing the water from an external source.
   This reset mechanism, is simple and reliable, because if the refilling of the crutch continued, the cable will pull further and finally stop the flow of external water. By contrast, ending of tracking at the end of the day can be problematic, both because of the simultaneous action needed for the two flows -- out of the crutch for tracking and into it for resetting. But more significantly, if the sun stops shining and never reappears during the day, the collector can be arrested at that point, and the resetting function can never occur. Human intervention in that situation is called for; or, if the next day is sunny, the tracking action will restart at the point when it was previously arrested for lack of insolation.

TRACKING AND PHOTOVOLTAICS

Using our new and more reliable hydraulic tracker, it is possible to construct mountings for any number of PV panels, which move in any prescribed relation to the position of the sun. With increased efficiency of eliminating any cosine effects of power generation of the panels, the returns to the very low cost of hydraulic tracking may be truly enormous.  We are in the process of testing practically the efficiency effects of our tracker and hope to report them in the future. Actually such results
must be available from other PV trackers, such as the well known freon-based
solution (e.g. from Zomeworks Co.).

SOLAR OVEN AND DRYING MECHANISM

   This year we had the idea to transform our solar ovens into drying mechanisms.  We used the usual concentrating oven with the solar concentrating panels for high-temperature preheating; in a second stage we used a large oven [about 3 times 3 feet] without concentrating panels. For both ovens it was necessary to increase the airflow by slightly lifting the glass cover at the top [north] side using a twig about 1/4 inch, and for the large "slow" drying oven we made a small aperture, some 2 inch square at the bottom [south] side to permit good flow of air by convection.  More is said about the use of this technique for cooking specific foods below.

MULTIPLE PURPOSE GREENHOUSE AND DRYING SYSTEM

 Another possibility of multiple use cost reduction especially in the case of
larger-scale operation [such as organic farming on one or a few acres] is to
use a large, several yards long low greenhouse [cold-frames] in spring, with
permanent south-inclined glass cover for growing of seedlings, and later in
the year when products such as tomatoes are ripening, transform these into
drying devices on a larger scale. This can be done by inserting black metal
plates below the glass for several inches and providing for appropriate vents
for air circulation.

COOKING AND BAKING WITH THE SOLAR OVEN AND DRYING SYSTEM

        Returning from a stay in Europe in early August, J. and W. Vanek found
themselves at the start of a tomato harvest that proved to be unexpectedly good. This situation provoked an experiment in sun-drying tomatoes in our rectangular and bakery size ovens.  We are happy to report considerable success.
        Our method was to wash then cut small tomatoes: we used small plum tomatoes and also cherry tomatoes, which aren't very good for other cooking uses.  We cut the cherries in half and the plum tomatoes mostly in quarters lengthwise, unless very small. The fruits were placed cut side up on dark cookie sheets, and went first into our rectangular baking oven on sunny days, but with no special care in tracking the sun as we didn't wish the oven to heat too hot.
        Once the tomatoes were well heated and a portion of the moisture evaporated out (shown by fogging on the glass oven door), we moved the tomato-filled sheets to our large, 3 x 3 foot bakery oven, using it without the concentrating reflectors.  In addition, we chiselled a V-shaped opening into the base of the oven frame to let air flow in and allow moisture to escape; and also cracked open the glass window with a twig or small piece of wood.  At intervals, every couple of hours, each tomato was loosened from the baking sheet with a spatula.
        Many times, the tomatoes were dehydrated and rubbery at the end of the
solar day, but not fully dry.  In this case we'd remove them into the house overnight and continue next (or next good) day.  Very often--though not always--the process continued over two days until a batch was fully dried.  So, it's a slow work; but the results are delicious, need no refrigeration nor freezing, and can be enjoyed all year long!
        Italian tomato sauce: we also found that once a pot of tomatoes had been stewed on the stove, heating it in the solar oven (using the oven in the normal way, with reflectors and tracking) while adding the herbs and other ingredients for Italian recipes produced an excellent sauce, thick and with very good flavor.  This cooking took probably an hour.  Next year we'll try this sauce "from scratch" by solar oven.
        Mushrooms: having come on some good edible mushrooms while on a walk
(and verified that they ARE edible--one cannot be too careful on that score), we
dried some of them in a manner similar to the sun-dried tomatoes.  The clean mushrooms were cut in bite-size pieces and placed on a cookie sheet in the oven.  The mushroom pieces were fully dry in 2 - 3 hours of a single afternoon, in good solar conditions.  Thus we saw that relative to the tomatoes, they contain more solid substance and less water.  But like the sun-dried tomatoes, they may be stored simply on a shelf in a container.
        Oldies and goodies: while developing new recipes and ways to use the solar
oven/cooker, we surely don't want to forget our old favorites.  Cooking a batch of rice in the oven is certainly one of ours: we prefer solar rice to what we make on the stove.  We allow an hour, but on a good solar day our rice was often ready in 30-45 minutes; and on a half-cloudy day, or when we left to do other things and so neglected to track, the rice most often cooked anyway!  Other main dishes we have enjoyed and recommend to carnivores are roast whole chicken, meatloaf, and pork roast.  These
all require good solar conditions and a dark, preferably heavy roasting pan.  We also enjoy heating soups, bread and rolls in the oven, just quickly.  And on a good day we had a delicious loaf of solar-baked whole-wheat bread.  The types of food we have NOT (not yet?) managed to produce in the solar cooker are any fried foods, or quick cooking requiring very high temps.--for example, sizzling a steak.  But we are well
content with what we can do, and invite your additions to the roster.

DONATION OF SOLAR OVEN TO INTERMEDIATE TECHNOLOGY U.K.

This year the STEVEN Foundation donated a rectangular oven (2 x 1 foot) to Intermediate Technology UK, otherwise known as "I.T.", based in Rugby, England.  This organization works in many developing countries, promoting not only solar energy but also low-cost construction techniques, sustainable agriculture, and other skills.  We hope that I.T. will be able to demonstrate use of the oven either in England (where sufficient sun for cooking, while infrequent, does sometimes happen!) or in one of the countries in which they work.  In our experience, many of the solar oven designs being used at present, while easy to construct, do not take full advantage of available sun and insulation materials and therefore do not reach a high enough temperature to cook rapidly.  Since this is one area where the STEVEN oven performs quite well, we hope that some aspects of the design might be disseminated through our collaboration with I.T.

NEW EIGHT-SIDED OVEN REFLECTOR

Although the STEVEN Foundation has been working with solar ovens for some 13 or 14 years by now, new improvements are always possible.  We have recently realized that the four-sided oven reflector with trapezoidal sides is less efficient than it could be, since sunlight striking the corners of the reflective sides is not in fact channelled into the oven, and is in this way lost.  We are therefore currently developing an eight-sided oven reflector, with four main rectangular sides along each edge of the oven, joined together by four smaller triangular sides in each corner.  This layout will give the maximum possible capture of sunlight for a given cross-sectional opening at the top of the reflector.
 

DEVELOPMENT OF "SUPERBIKE" FULL-BODY DRIVE BICYCLE TECHNOLOGY

REVISIONS OF THE SUPERBIKE DESIGN

In order to test the superbike Jaroslav has adopted it as his only means of bike transportation and exercise, and Francis has frequently ridden the superbike in order to gain experience with it. After several years the bike was found most satisfatory fulfilling all its expected qualities [see the website www.people.cornell.edu/~jv19] -- but with one major exception which lead us to a basic revision.  The coaster brake on the front wheel which we felt was so useful in many respects has one major disadvantage, in that it can freeze up, or block when applied with force -- the same as with automobile brakes. But in the case of a front wheel on the bike this can become quite dangerous, and could be undone only with an antiblock device which, to the best of our knowledge, does not currently exist for bikes.  From this we concluded to give up our front coaster brake, and we produced three basic alterations, which are described next: 1) the simplex version, 2) the front gearshift version, and 3) the rear coaster brake with gearshift.

1. THE SIMPLEX VERSION

In this simple case the wheel with a single gear and the coaster brake is moved from front to back of the bike. This makes the major difference that if ever the brake would lock the bike will simply start skidding without any danger of major accident. One has now even better and more powerful control over the brake. In addition there can be one or two additional brakes mounted on the stem of the bike, connected to calliper brakes on either or both of the wheels. A single or multiple gear hub, formerly in the
rear, but without brake, is now moved to the front of the bike. In this simplex
case the availability of a front drive becomes quite significant, as with only one speed (one gear) in the back the front wheel with the front wheel drive pedals not
only provide the additional power and control implied in the superbike design,
but the frontwheel drive now practically substitutes for the gear shift.  One rides the bike using the power of the single rear speed, and when one comes to a hill, or starts riding in a difficult terrain, one supplements the power of the legs with the power of the arms.

2. THE FRONT GEARSHIFT VERSION

Francis has installed a complete gear shift mechanism on the front wheel of the altered design. This can be combined with the coaster brake in the rear.  The availability of gears in the front permits the drive ratio to be tailored to conditions: a low gear for climbing up a steep hill, or higher gear for front drive on level ground.  A superbike with gear shift on both front and rear drive is contemplated for the future.  As we have not yet arrived at a final design for brake levers mounted on the stem, we are continuing to build only prototypes with some form of rear coaster brake at this time.

3. REAR COASTERBRAKE WITH GEARSHIFT

It is also possible, usually at considerable additional cost, to use a coaster brake in the rear together with an "internal" gearshift mechanism -- usually based on only three different gears --built into the hub of the rear wheel.  Except for the additional cost this may be a very desirable solution for the superbike.
 

SUPERBIKE WITH CHAIN TENSIONER

This year Francis built a prototype superbike with chain tensioning in the front drive, i.e. with a spring mechanism to take up any slack in the chain, as in the function of the rear derailleur in the conventional drivetrain found on mountain bikes and racing bikes.  This tensioner eliminated the need for stiffening rods between the superbike stem and the tip of the front fork, as the flexing of the stem-fork system while the front drive is pedalled no longer causes the chain to derail.  The mechanism was tested over many miles of riding and found to be quite reliable, not having allowed the chain to derail in a single instance.

In addition, since this prototype was assembled and tested in Edinburgh, Scotland, it provided a test case of the kit-building approach to the superbike.  A kit of required parts was gathered and shipped from Ithaca, and these were then installed on a conventional hybrid bike in order to make the superbike.  It was also necessary to have a wheel specially built locally in Edinburgh for the front wheel.  We were pleased with the outcome; the kit can be shipped in quite a compact form, and the total cost can be kept down relative to the delivered cost of a complete bicycle, so this approach may provide the way forward in the future.
 

OUTREACH WORK OF THE FOUNDATION

VISIT TO THE CENTRE FOR ALTERNATIVE TECHNOLOGY, WALES

   In June of this year, Francis Vanek visited the Centre for Appropriate Technology, or C.A.T., in Machynellyth, Wales.  This center was developed on the site of a closed slate quarry some 20 miles inland from the Irish Sea in the 1970s, and has grown into what is said to be largest center of its kind in Europe.  A water-powered funicular railway carries visitors from the parking lot up to the center itself, and then a circular path leads through an array of displays on sustainable building, photovoltaics, organic gardening, and wind power.  The main purpose of the center is to demonstrate these technologies to the general public, for which they charge a modest admission price but they also carry out some research and consultancy work.  They practice what they preach, as well: all of their electricity and most of their heating comes from a mixture of wind, water, and solar power.
   During the visit, Francis met with Phil Horton on the C.A.T. staff to talk about the possibility of collaboration with the STEVEN Foundation.  Areas of overlap are mainly in alternative energy applications for the wealthy countries, including solar tracking and steam-driven solar devices.
 

PUBLICATION OF CHAPTER IN APPROPRIATE TECHNOLOGY HANDBOOK BY HAZELTINE & BULL

A chapter written by Francis Vanek entitled "Design Philosophies for Appropriate Technology" was recently accepted for publication by Barrett Hazeltine and Chris Bull of Brown University for their upcoming handbook on appropriate technology.  The chapter briefly describes some guidelines for assessing the situation in the field and then making appropriate decisions during the design process.  The chapter will appear in the introductory section of the handbook, which then goes on to provide numerous short chapters, each dedicated to a specific technology, ranging from water pumping to providing services such as micro-lending institutions.  An electronic copy of the chapter can be obtained by sending email to Error! Bookmark not defined..
 

EDITORIAL – "Harnessing our inventive energies for developing countries and the environment"
by Francis Vanek

Working in the field of appropriate technology, one is often struck how, despite the enormous range of creative, elegant, and at times amusing technologies that have developed, the need for implementation in the field remains seemingly vast.  For any need in any village or town in the developing world, one can envision the type of technology that could be applied, and yet in so many places, and for so many impoverished people, that vision has stubbornly refused to become a reality.  In some instances, what is lacking is the exact appropriate technology that will meet a specific need, but in many others, the idea already exists, and what is lacking is the time, funding, access to information, and "elbow grease" to bring the idea to fruition.

At the same time, we do see around us, in the developed world, time and energy being put into all manner of creative projects – fixing old cars, building additions onto houses, wood- and metal-working, constructing models, making pottery and handicrafts, and the like.  These activities seem to me to meet a basic human need, away from the demands of family or work life: to work with one’s hands, to be in personal control of a process, to have the creative freedom to solve a problem in one’s own way.

Could it be that some of this energy could be channelled in the direction of appropriate technology, without any loss of the other benefits that are gained?  Perhaps a person with creative and artistic skills could become involved in the process of designing a technology for a specific project.  Or else they might take part in the fabrication of some device, either in their home location or by traveling into the field to work on a project.  Or perhaps the extension of the realm of appropriate technology (for all its current diversity) is their calling, and they may wish to do some tinkering to design a new pump, solar cooker, or the like.

Broadening the scope for involvement in this way may be especially relevant to creating appropriate technology locally in the developed world (sometimes called alternative technology).  When people invent their own solution for a design problem in their home or community, they tend to develop technologies that are decentralized and also contain a relatively large component of "sweat equity", so that costs are kept relative low.  Taking the example of the household, almost any application might be addressed: transport, lighting, refrigeration, toilets, heating, insulation, waste management, and so on.  Although this type of work does not represent a direct contribution to developing countries, it benefits the environment by allowing the developed citizens to live more lightly on the earth, freeing up natural resources and reducing the global strain on the environment.

One could of course be skeptical of the mainstream appeal of this approach beyond a narrow community of committed environmentalists who are already reinventing their homes and the way they live.  Can a person whose hobby is repairing antique cars become interested in installing passive solar into his or her home?  I recall an experience I had which illustrated the unexpected commitment one sees to ecology from all parts of society.  When I lived with my family in Philadelphia, PA, we took our recycling (that which the city did not collect) to a center in neighboring Pottstown.  Although not known as an environmentally progressive community, this small city of perhaps 30,000 people was supporting an outstanding recycling center, and each time I came, I was impressed with how diverse the clientele was – they were not all bicycle-riding vegetarians like me!  In a sense, Pottstown had lucked into recycling by chance.  What if every community of this size had a similar recycling center?  Likewise, what if each community and neighborhood, each home, even each garage, had an individual or group interested in designing and building appropriate technology?  The volume of work that could get done would, I think, be truly remarkable.


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