Website: www.virtualithaca.com/francis/stevenhomepage.html
NEWSLETTER 2008
Welcome to our 2008 newsletter, describing the continuing efforts of the S.T.E.V.E.N. Foundation. We regret the delay in updating our circle of friends about 2008 activities only now in early 2009. In any case, we continue to work on simple, low-cost technology designs while disseminating information to those who request it.
While there was quite a bit of research and testing activity
this year, there are very few definite results to report. The principal
activity was in the area of low-cost wind energy. For the most part we dealt
with vertical axis turbines, trying to construct something wind resilient and
at the same time of low cost. Since with a four-winged wheel there is some
problem of partial “shading” of one wing by another incoming [as if two
sailboats were travelling side-by-side in a crosswind] we tried two
solutions. First, perhaps inspired by
large commercial wind turbines, we constructed a model
with only three “sails.” Alternately, we are trying to superimpose two
two-winged rotors, one atop the other at cross angles, so that there would be
no “shading” at all. This is now our
principal approach in research and testing.
While we have a good deal of hope, there are as yet no definite results.
In conjunction with these attempts, we are now using inexpensive wings which act as a one-directional filter or valve for wind, which in addition are easy to remove from a skeleton turbine structure in case of very strong wind. Because with slow turning rotors we face the problem of reaching high enough rpm’s for an electric generator, we have developed an inexpensive method of using the entire slow moving rotor as one of the gears to match with the gear of an alternator, thus having only a one-step multiplication of rotation.
At one time this year we cooperated with a Cornell engineering graduate who works on – and apparently has patented – a wind engine which works in a pendulating manner, using the principle of rowing with turning the position of the oar into and against the wind. We even built several testing models of the device, but on the whole with poor results: thus we have discontinued the cooperation.
Yet another
design of which we constructed a model-- and tested it on Atlantic beaches-- is
what we call the Hurricane turbine. We
believe this design could work in very strong winds, especially if constructed
of armored concrete. In its shape it
resembles a horizontally placed Missisippi steamer
paddle wheel, with its axis perpendicular to the wind direction, and the lower half of the wheel “shaded”
by an inclined wind deflector concentrating all wind onto the upper portion of
the wheel. A small prototype was tested on the shores of the
Showing the continuing need for such devices, our icemaker design continues to be the subject of inquiries, over 12 years after it was described in Home Power magazine. For the article, see www.homepower.com, #53, June/July 1996; or you may contact us for a photocopy.
Again this year we report that no work has been done toward converting the icemaker into a true refrigerator. If someone wishes to take on that challenge, we could offer some support from our experience. Equally, we could advise anyone who wishes to build an icemaker as the model stands now.
Design instructions have recently been uploaded to our website for a modified “S.T.E.V.E.N.-style” solar oven, which incorporates a number of convenient improvements into the basic design. This new oven design maintains the insulated box with 8-sided reflector for concentration of sunlight into the oven space. However, the top of the oven has a diagonally tilted glass opening, instead of a horizontal opening, so that the oven can face toward the sun more easily while resting on a flat surface. Also, access to the interior of the oven is through a hinged door at the back, rather than by lifting the glass off the top.
Thanks go out to the students of the Cornell Engineers for a
Sustainable World (ESW) organization, who documented the design in a form that
we could upload to the website, and also built a prototype which was donated to
the Ecovillage at
www.virtualithaca.com/francis/stevenhomepage.html
or you can write to us for a paper copy of the plans if you do not have easy access to the internet.
We can supply 3-M Mylar from our relatively small stock, for
individual needs or experiments, such as solar box cookers or a single solar
parabolic collector. The Mylar comes on
rolls about 5 feet wide. We can cut and
ship in a mailing tube: we are asking $1. per square
foot, including shipping in