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Posted by William Wixon on February 17, 2008, 12:12 am
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>
> Frankly, I'm skeptical of the design. It looks like it will just clear
> some of the tree tops (lot of turbulent air at that level). Without a
> close look at the padels I can't tell what the drag would be like on those
> padels as they traverse back 'upwind'.
>
> I don't see any information about the average wind speed at that location,
> so it's impossible to tell what Ikeda's claims for this really mean. With
> an aspect ratio of roughly 2:1, it looks like it might have a swept area
> of about 6000 ft^2 (562 m^2).
>
> To produce 3.69e6 kW-hours per year, in a perfectly steady 24/7 wind, it
> would have to average 421 kW output. If it were to operate at the
> theoretical limit for any wind machine, that would mean 714 kW of wind
> power flowing through those 562 m^2. That's about 1270 watts per m^2.
> With air density of about 1.2 kg/m^3, that would require a constant
> windspeed of 12.8 m/s all year long. If I got my sums right :-).
>
> That's over 28 mph, 24/365 and I'm pretty sure it's not that windy there,
> especially just above the tree tops. And I'm quite certain that this
> design doesn't extract the theoretical maximum. Unless the reporter made
> a typo and that's supposed to ready 3.69e6 watt-hours, I don't believe it.
> (but that would mean an average output of just 421 watts for such a large
> unit).
>
> I'm glad the board at least put a proviso to review the performance after
> a year of operation. I think they'll be very disappointed.
>
> daestrom
>
thanks for reading the article and responding to my post.
b.w.
(i know, it does look kinda hokey huh? i was hoping though that somehow it
was going to work out ok for everyone involved.) (it's nice that a local
college is getting involved in such stuff and that Ikeda is footing the bill
for it.)
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