dpb wrote:
....

One problem w/ wind is that even here in SW KS known for being one of
windiest places in the US the wind doesn't blow all the time,
particularly less in Aug and Feb, the two peak months and at night when
lose thermal heating effects that contribute. The Gray County farm has
averaged only about a 40% capacity factor since it went online in 2002
or so based on their reported generation to DOE/EIA that I looked at a
year or so ago. The maximum monthly average was just over 50% for a
couple of months while the two slack months were in the mid-20% range.
That means need 2.5X extra installed capacity to make up the target
generation on average and 5X in weak months. That's a real construction
burden to do more than augment conventional technologies.

Those statistics were for seven years of operation and were quite
consistent from year to year in the monthly peaks and valleys reflecting
climatological trends, not just a one-year aberration.

The data were only available on a monthly generation basis so the
extremes in availability would be greater as looked at shorter time
periods if that level of reporting were available. Last week in the
doldrums SIL came by the wind farm on way here for visit and reported
only 2-3 of the whole installation were turning.

While the fuel is free it isn't always being delivered and is a diffuse
source so takes a lot of infrastructure to concentrate it into useful
form. That translates to $$/kw on grid; I don't think there would be
any significant interest by utilities at all if it weren't for the
various State-legislated mandates for percentages of generation from
green sources passed onto the utilities and the various tax incentives
to subsidize part of the cost.

Whether it will be cost-competitive eventually w/o those is anybody's
guess; certainly C-taxes if introduced will change the playing field
immensely in foreseen and unforeseen ways (and I personally expect more
of the latter than former). Unfortunately, however much scale and
technology improvements benefit the capital cost/installed-MWe, the
fundamental nature of the intermittent fuel supply can't be improved or
eliminated so the required conventional reserve capacity will still be
required which essentially doubles the cost for every MWe that isn't
available or reduces grid reliability if not there.

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