Seasonal wind power variation

Lu, McElroy, and Kiviluoma (PNAS 2009)

Graph says it all.

PNAS | Global potential for wind-generated electricity

(Hat tip Green, Inc. blog)

Wind potential varies over the year by a factor of two. There's absolutely no reasonable way of storing half a year of electricity on a grid scale. So these huge seasonal variations are terminally bad - either you build enough wind capacity to function through the August nadir, and throw away the excess in other months - at huge loss - or you run natural gas turbines for half the year - with huge CO2 emissions. Or both.

The authors don't actually suggest any solution, besides the brief remark that "energy-rich chemical species such as H2 could provide a means for longer-term storage." Ehh... no.

The paper has some other interesting stuff - a physical model to extrapolate 100m-level winds from ground meterological measurements; and some correleation coefficients between different locations.

One thing that is certainly missing is shorter-term wind fluctuations - timescales not of months, but days. How much variation is left when you sum together a very large region? I think that could be worse than the seasonal mode. I've thought up a model for using METAR data to answer this question, but I'm lazy and haven't done anything in weeks. Also, major puzzle pieces are missing, such as a 100m-level extrapolation method (maybe just linear?), a way to distribute farms (to maximize power, minimize variation) and something approaching a coherent methodology. :(

A couple snapshots to show where I am (data from NOAA; shows cube of wind speed on July 10, 12-1 AM):

METAR wind data (v^3); graph by me

Voronoi cells

1 comment:

  1. But check out this article in today's times:
    http://greeninc.blogs.nytimes.com/2009/11/09/brazilian-wind-power-gets-a-boost/

    In Brazil, wind power's seasonality is complementary to hydropower's seasonality, since dry season winds are stronger and more reliable.

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