foreword by Paul Gipe
Hugh Piggott's plans for turning a used brakedrum into a windmill is
welcome addition to the literature on small wind turbines. "Brakedrum
Windmill" is especially valuable because plans for building your own
wind
turbine have not kept pace with the technology. Most plans date from
the
1970s--or even earlier.
Better yet, the plans in this booklet are for a wind turbine that really
works from someone who lives with and depends on wind energy. The brakedrum
windmill is a proven design that Hugh has operated at a remote, windswept
headland in northwest Scotland since 1993. His site on the Scoraig
Peninsula is so windy in fact that several commercial wind turbines
failed
within a few years (some, unfortunately, much sooner). Hugh's prototype
of
the brakedrum windmill in these plans has operated so reliably that
he
substantially increased its output within a few years after installation.
And it continues to run to this day.
The beauty of these plans can be found in Hugh's use of conveniently
handy
scrap yard parts. The design is based on rear brake drums used by Ford
trucks widely available in both Britain (the transit van) and North
America
(the F250).
Another plus is Hugh's elimination of slip rings and yaw bearings. Slip
rings often bedevil the design of commercial wind turbines as well
as home
builts. They're not necessary and seldom found on many wind turbines
built
in Europe. Hugh wisely avoided them, instead substituting a simple
pendant
cable. This greatly simplifies this design as does Hugh's use of
pipe-on-pipe for a simple and hardy yaw system that allows the turbine
to
respond to changes in wind direction.
Hugh's brakedrum windmill also incorporates the durable "inside out"
alternator design found in the popular--and successful--small wind
turbines
built by Bergey Windpower and World Power Technologies. With this
alternator configuration there's no need to build a complicated hub
that
attaches the blades awkwardly to a small diameter shaft as in some
other
designs. Instead a simple plywood sandwich holds the blades tightly
to the
rotor and this assembly is mounted directly to the generator housing:
the
brake drum. In wind turbines it doesn't get more straight-forward than
this.
And like all reliable commercial wind turbines today these plans use
"self-furling" to protect the product of your labor in high winds.
Hugh's
an expert on this technique to limit the speed of the wind turbine's
rotor
and the simple design found in these plans would be helpful to not
a few
commercial wind turbine companies who haven't quite mastered the art.
"Brakedrum Windmill" includes detailed instructions for building the
entire
wind turbine, from carving your own blades for a 7-foot (2.1 meter)
diameter rotor to building your own permanent-magnet, direct-drive
alternator capable of generating real power. By following these plans
you
will construct a genuine wind turbine--not just a toy--that can reliably
churn out 300 to 400 watts.
"Brakedrum Windmill Plans" are a great companion to Hugh's "Windpower
Workshop." Both are a valuable addition to any windmiller's library.
Paul Gipe
Wulf Ranch Test Field
Tehachapi, California
October 1999
Paul Gipe
208 S. Green St., #5; Tehachapi CA 93561-1741 USA; ph: +661 822 9150;
fax:
+661 822 8452; [email protected]. Wind Power for Home & Business (Chelsea
Green
Pub., 1993), Wind Energy Comes of Age (John Wiley & Sons, 1995),
Wind
Energy Basics: A Guide to Small and Micro Wind Systems (Chelsea Green
Pub.,
1999). <http://rotor.fb12.tu-berlin.de/personen/paul.html>