February - March 2008
the vertical revolution
Wind turbine
Editor’s note: Every story in this section should start off… ‘At $100 a barrel for oil, blank is starting to make more sense.’ We all knew this time was coming. Well, now it’s here.
By Alvin Koo
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It started, as far as we know, about 5,000 BC with wind powered boats going across the Nile. Persians used windmills to grind grain in 1000 AD. That creaky old windmill for pumping water you saw in the Old West, that’s 1850. Next year, there will be a huge 5 mW wind turbine built offshore in the Scottish North Sea.
And today… there is the vertical axis wind turbine.
Not like those old west cowboy windmills.
Or those huge blades you might remember being out in Kahuku.
Most industry experts say the Kahuku experiment failed because of the corrosion caused by the combination of wind, salt, sand and moisture on the metal and wood materials, then the vibrations from the blades shook the machine to death.
They say the technology is much better now.
You see, there is a slight problem with horizontal axis windmills. They’re noisy, transmitting low frequency noise from 40 to 50 db, gravity: you have a large, heavy blades spinning out in space that gravity wants to tear down and, in heavy winds, they have to shut down or they will self-destruct.
So, now we have the vertical axis turbine in a myriad of shapes and styles.
In Hawaii, Energy Management Group sells the PacWind line of vertical turbines.
Vertical turbines offer advantages: they operate in low, mediuim and high wind speeds, with only one moving part, they require practically zero maintenance and they are virtually noiseless.
The noise you hear from a windmill comes, not from the shaft squeaking, but from the fans creating wind turbulence.
The machine is so good that Jay Leno is installing them in his house in Burbank. He helped promote it with an article in Popular Mechanics.
Richard Figliuzzi, president of Energy Management Group in Hawaii, is testing a 10 kW VAWT like the one that Leno used at a site near the Honolulu International Airport.
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It showed an average of 3.8767 kW output or 38 percent of its maximum. Based on a 17.5 cents per kW hour electricity cost, the annual return was $5,943.02 with an estimated installed price of approximately $40,000 before Hawaii and federal tax credits. PacWind has a 500 W model for $3,000.
Windmills have come a long way.
PacWind is installing their vertical axis machines on the top floor of the new San Francisco Public Utilities Commission building.
The question is: can we use them in urban Honolulu?
The answer is: yes, of course.
PacWind claims to have overcome early problems of cost and ineffiency with old vertical axis machines. Theirs are designed to be mounted nearly anywhere, the higher the better.
The leading edge of buildings or roofs create an acceleration of wind speed. The PacWind turbines can be mounted to the sides of a house or building or above the roof line. You must work with the installer to determine the best location and mounting specifications.
Alvin Koo has been a writer and public relations practitioner in Hawai‘i for 30 years. His book “Stuff Nobody Told Me” can be found at http://papaalhawaii.htohananet.com/stuff.htm.
