Wind Energy Institute of Canada (WEICan) completes the first real-world
test of WhalePower Corporation's bio-inspired, retrofitted wind turbine
blades. WEICan finds the blades work and Annualized Energy Production
(AEP) enhancement is "promising." WhalePower's analysis of test data
shows tubercles applied to the leading edge enhance operational
stability, durability, quietness, and significantly improve AEP. WEICan
recommends direct comparative tests.
TORONTO, Jan. 22 /CNW/ - WhalePower Corporation announces today the end
of an independent study by WEICan of WhalePower's Tubercle Technology, modeled
on the aerodynamic properties of the leading edge tubercles on Humpback Whale
flippers. The WEIcan tests were conducted under the International
Electro-Technical Commission (IEC) standard for small wind turbines. Previous
mathematical and wind tunnel studies had demonstrated that leading edge
tubercles create a new kind of air foil. The WEICan tests were the first study
of a bio-mimetic air foil in unsteady air on a rotating platform, in this case
a Wenvor Technologies 25 Kilowatt turbine with a 10 meter span.
WhalePower retrofitted two Wenvor blades with tubercles on the outer 60%
of their leading edges, with support from a grant by the Ontario Power
Authority. They were installed on WEICan's Wenvor test turbine at its North
Cape, Prince Edward Island site in July 2007. With grant support from Natural
Resources Canada, WEICan personnel gathered data between December 2007 and
June 2008. As these tests were conducted, WhalePower also developed and tested
tubercles on the full lengths of each 12 foot span, high volume-low speed
(HVLS) fan system for Envira-North Systems Ltd. of Seaforth, Ontario.
The WEICan tests did not directly measure the engineering feasibility, or
the tubercle fabrication durability, but focused on the performance of the new
airfoil in a real world setting on a commercial turbine. Nevertheless, in all
these categories, the blades performed admirably. It was not possible to do a
straight comparison of AEP between the modified, and the unmodified Wenvor
turbine. Though it had been previously tested by WEICan's predecessor, the
Atlantic Wind Test Site, the turbine had not been characterized according to
the IEC protocol, and those original Wenvor blades were unavailable for
modification by WhalePower.
Still, conclusions about tubercle performance may be drawn.
1. Operational stability was demonstrated and the blades were quiet.
Subsequent analysis of air flows on the fully tubercled HLVS fans
demonstrated that where tubercles are applied, there is dramatic
stall reduction as air stays attached to the blade. Further
improvement can be expected with tubercles on the full span of wind
2. Blade durability was demonstrated though no formal durability test
was conducted. The turbine was exposed to winds in excess of
100 km/h, thunderstorms, and a very severe ice storm that knocked out
most of the PEI power grid. The retrofitted blades were undamaged and
collected little or no debris while rotating. When locked off, the
blades accumulated ice, but when allowed to rotate, they shed the ice
3. AEP increased by an estimated 20%. The power curve WEICan measured
shows power generated at wind speeds of approximately 5 meters per
second (m/s) and peak efficiency at 9 m/s. Rated power was attained
at 12.5 m/s versus the 15 m/s previously published performance for
the unmodified Wenvor turbine. WhalePower's analysis of both Wenvor
and WEICan data, by Dr. Laurens Howle of Duke University Pratt School
of Engineering, shows an approximate 20 percent increase in AEP
despite the fact that tubercles were applied on just the outer 60% of
the un-optimized Wenvor blades. Greater efficiencies still were
measured by Envira-North's tests of WhalePower's fully tubercled fan
The WEICan data supports WhalePower Corporation's conclusion that future
R&D on turbines should incorporate tubercles on the entire length of optimized
blade shapes to fully measure what these new air foils can contribute to the
production of energy in all wind speeds while reducing stall and noise. WEICan
also recommends direct comparative tests be done.
"An improvement of just 1 or 2% in AEP is significant," says Stephen
Dewar, Director of R& D at WhalePower. "Here we have about 20% with low noise.
We're thrilled by this result."
For the full WEICan report and WhalePower analyses, please see the
WhalePower Corporation website at: www.whalepower.com.
For further information:
For further information: Stephen Dewar, Director of R&D, (416) 651-7559,
stephen.dewar@WhalePower.com; For information on tubercled HVLS fans, please
see: www.enviranorth.com or write Mbowden@Sunnorth.com