Sorting out Some Claims About Danish Wind Power

Michael Giberson

A shortened version of Michael Trebilcock’s commentary on wind power, mentioned here the other day, was published in the Financial Post under the not so subtle title of, “Wind power is a complete disaster.”

The Financial Post subsequently published a reply by Sigurd Lauge Pedersen, a Senior Adviser to the Danish Energy Agency: “Wind power works.”

Trebilcock is back in the Financial Post with “The myth of the Danish green energy ‘miracle’.”

Pedersen begins, “It is perfectly legitimate to hate wind power. But it is more convincing if you do your homework first.” Trebilcock, in his reply, begins by casting aspersions on the Danish government’s sensitivity to criticism of their wind power experience. Both authors have some helpful points to make, but I object to the unnecessarily strident and snide tone of the exchange. (Hey, that’s what blogs are for! -ed.)

If Pedersen had done his homework, say by reviewing the Arthur Campbell paper cited in Trebilcock’s submission to the Ontario Legislative Committee on the Green Energy Act (mentioned in the original op-ed), Pedersen would have realized that claiming wind power raises CO2 emissions is not absurd. Instead it is merely unlikely.

If Trebilcock were more careful, or maybe if he understood wind power better, he’d have avoided the modest non sequitur of, “Most wind turbines run at about 25% of rated capacity, requiring back-up generation for the balance of the time.” No one, so far as I am aware, expects to get a constant 100 percent of nameplate capacity delivered from their wind power (or any other) generation, so what “balance of the time” is he referring to?

It is well known that “facts” circulating in public discourse sometimes stray from their original meaning, so it is sometimes useful to track down sources.  In the continuation I try to sort out two disputed claims made by Trebilcock in his first Financial Post op-ed.

One factual matter of dispute is whether or not Denmark has closed any fossil fuel plants as it has added wind power capacity. (Treb.: “Denmark … has yet to close a single fossil-fuel plant.” Ped.: “There is no citation for this claim, which is wise, in a sense, for the claim is wrong. Denmark has closed several coal and oil fired plants in the last 10 years.” Pedersen offers no citation to support his claim.

Trebilcock and Pedersen also debate whether or not C02 emissions have gone up due to wind power. (Treb.: “[Denmark] requires 50% more coal-generated electricity to cover wind power’s unpredictability, and pollution and carbon dioxide emissions have risen (by 36% in 2006 alone).” Ped.: “Trebilcock claims that CO2 emissions went up by 36% in 2006 as a result of wind power. This does not make sense.  …the claim that wind power increases CO2 is absurd.”)

On both points, Trebilcock in reply said, “These claims are literally quotations from a recent detailed study by Tony Lodge, a widely cited writer on European energy policy.”  Excellent. The reference to Tony Lodge is the closest thing to a citation in this exchange, so I went looking for this “recent detailed study.” It turns out that Lodge is a “political and energy analyst” at the Centre for Policy Studies in the U.K. The “recent detailed study” is presumably Lodge’s report, “Wind Chill: Why wind energy will not fill the UK’s energy gap,” published last year by the CPS.

In “Wind Chill,” Lodge said, “not a single conventional power plant has been closed in the period that Danish wind farms have been developed.” (p. 6) Unfortunately, the claim is not backed up with any sort of reference. Examining the Danish Energy Agency’s report, Energy Statistics 2007, it is clear that Denmark had very little wind power in 1980, but significant wind power in 2007 (output of 38 terajoules in 1980 and 25,823 terajoules in 2007).  On the other hand, consumption of oil for electric power production has fallen (from over 47,000 TJ in 1980 to just over 11,000 TJ in 2007); as has consumption of coal (from near 214,000 TJ in 1980 to almost 167,000 TJ in 2007). If you’d rather think in gigawatt-hours rather than terajoules, you can divide the TJ numbers by 3.6 to get GWh.

I don’t find reports on numbers of powerplants, or plants retired, but it is hard to believe that “not a single conventional power plant has been closed” since 1980, given the reduction in output. Or else all of those oil-fired plants are operating with a poorer capacity factor than wind power in Denmark.  I’ll score Lodge’s claim about powerplant closures as undocumented, and agree with Pedersen that there is no citation for this claim (And Trebilcock’s claims are not “literally quotations,” and I’m not sure I’d characterize “Wind Chill” as a “detailed study”, either).  Of course, as noted, Pedersen doesn’t cite a source for his counterclaim, either.

On the second point Lodge said, “For example, the Danish grid used 50% more coal-generated electricity in 2006 than in 2005 to cover wind’s failings. The increase in the demand for coal, needed to plug the gap left by under performing wind farms, meant that Danish carbon emissions rose by 36% in 2006.”  (p. 7) This remark does come with a citation, “Energinet (Danish grid operator journal), February 2007”, I haven’t been able to trace that exact reference. However, the Energinet “Environmental Report 2007“, dated July 2007, does indicate that coal use and CO2 emissions increased in 2006 over 2005, but the report attributes the increases to the dry year (low hydro power condition) in the Nordic countries rather than to “under performing wind farms.”

In any case, writing in 2008, Lodge should have been aware that in 2007, Danish wind power capacity increased a little (comparing to 2006), Danish wind power output increased notably (from 15.8 percent of domestic electricity supply to 18.8 percent), and Danish power output from coal was off significantly (from 53.9 percent to 50.8 percent).  Sometimes there is a lot of hydropower in Norway and Sweden, and imports in Denmark (some re-exported further south) go up, mostly displacing fossil fuel generation. Sometimes there is not so much hydropower, and fossil fuel generation mostly takes up the slack.  It happened that 2006 was sort of an atypical year, which gave Lodge a dramatic number on emissions which he missatributes to wind variability, and Trebilcock repeats. I’m scoring Lodge’s claims on increased coal use in 2006 “to cover wind’s failings” as entirely misleading. Trebilcock was unwise to rely on this misleading claim. Pedersen’s counterclaims, “makes no sense,” “absurb,” suggests that he hasn’t looked too closely at the related literature. (As I noted in the earlier post, the best answer seems to be “It depends.”)

Sloppy, unscholarly, unscientific, and in sum, unreliable.

In all I find the exchange a little frustrating, but I suppose I shouldn’t look to partisan exchanges in newspaper columns for carefully supported facts and opinions.