Click images for more details



Recent comments
Recent posts
Currently discussing

A few sites I've stumbled across recently....

Powered by Squarespace
« UEA Literary Festival | Main | Gwyn Prins on Climategate »

Load factors

Rob Schneider has been looking at published figures for the amount of electricity generated by windfarms in the UK. He has then compared this to the installed capacity to get a feel for the true average load factor for wind power in the UK.

The figures are...well...take a look yourself.

PrintView Printer Friendly Version

Reader Comments (35)

I like to watch the wind NOT blow on this site.

Oct 31, 2010 at 8:40 PM | Unregistered CommenterTinyCO2

Roy - re: your request for more info. DUKES is a good source:

Oct 31, 2010 at 9:01 PM | Unregistered Commenternot banned yet

The really big problem with wind farms is getting God to schedule the wind when we need the electricity, and He seems not to give a fig about our needs.

What all the watermelons miss is that electricity is not storeable, unless you build massive reservoirs like the Storm King Pump Power Project, which was never built, or a massive number of batteries, which hopefully never gets built either.

I am actually surprised that they appear to get 10% load utilization out of the wind farms. I would challenge those numbers as being too high. And frankly, I have no idea what those curves are saying.

What I would like to see is MWH production verses MWH load. In short, over a years time, what percentage of actual power consumption was actually generated by the wind mills.

Oct 31, 2010 at 9:02 PM | Unregistered CommenterDon Pablo de la Sierra

Well, what a surprise....wind power isn't the silver bullet. Would we have ever guessed that. Mr Gore, what have you done. socialist propagandists, all. Wall, bullet, go figure.

Oct 31, 2010 at 9:05 PM | Unregistered Commenterjohn in cheshire

Sorry! That comment is to Rob - apologies.

Oct 31, 2010 at 9:11 PM | Unregistered Commenternot banned yet

Good article

We can use wind power to a certain amount, but beyond that it is a waste of time. It is more of a drag. It is already a drag.

If you hear about Denmark as an example then you wont hear the fact Denmark is a tiny energy market/supplier dwarfed by its neighbours to whom it can sell and offset demand at will, but is never factored in as a detrimental cost of wind power.

Basically using Denmark as an example for expecting all energy to be supplied by wind is like using Switzerland as an example of how we should all use Cuckoo clocks for accurate time keeping.

Wind is a lie.

Peeling Away the Onion of Denmark Wind

Oct 31, 2010 at 9:12 PM | Unregistered CommenterSteve2

And of course wind turbine consume electricity in lubrication, heating (de-icing), orientating systems etc. I have heard it said that some are turned by electric motors when the wind doesn't blow to prevent the bearings seizing, which of course would give the inadvertent impression that they are working when they aren't.

Oct 31, 2010 at 10:18 PM | Unregistered CommenterThe Englishman

Perhaps the UK government will be able to run the wind farms in reverse and pass them off as an interesting form of modern sculpture, of considerable cultural value. (This may actually be economically more efficient).

Oct 31, 2010 at 10:23 PM | Unregistered CommenterZT

There's not much new here. The campaign groups have been publishing this sort of info for ages.

In some sort of order:

Nov 1, 2010 at 6:44 AM | Unregistered CommenterPhillip Bratby

@ not banned yet

Thanks for the pointer to the DECC "data to download" site at There are many spreadsheets of summary data which I will explore and compare/contrast as best I can. I looked for but did not find links to any source data from which was used to produce all the different slices/dices of the data in the many spreadsheet files. I'll keep digging there. Surely is somewhere but if published is a question.

Nov 1, 2010 at 6:59 AM | Unregistered CommenterRob Schneider

@ Phillip Bratby,

Thanks for the links. It was the discovery of the Caithness Wind Farms which first put me onto this exploration. I'm aware of some of the links you provide and some are new to me. CLOWD looks particularly intriguing.

At first glance I notice there is a lot of summary data provided but not so much source data. And where summary data provided it's difficult to impossible to "munge" into a form for other analysis. I'll pursue all and assess (for example first step would be to compare the summary numbers). I'm looking for more source data as I have some ideas about taking a slightly different view of the data for purposes of looking ahead into the future--dangerous as that might be.

Nov 1, 2010 at 7:20 AM | Unregistered CommenterRob Schneider

Rob Schneider:

Good luck with the task. All I would say is try and make sure it hasn't been done before. I suggest you contact John Constable at the REF. I think REF get raw data on wind farm performance from raw ROC data. I am sure that he will be willing to provide any data and help that he can. I can provide an email address and phone number if you get in touch with me.

Nov 1, 2010 at 7:41 AM | Unregistered CommenterPhillip Bratby


The ROC data are available at

Nov 1, 2010 at 7:55 AM | Unregistered CommenterPhillip Bratby

Perhaps you could alter the pitch of the blades on these things from vertical to just short of horizontal and generate some lift. Correctly aligned, hundreds of thousands of these could lift and deposit your island nation a few hundred miles to the north. Thus reducing the extreme temperatures you have been experiencing during summer, due to global warming, climate disruption.

Nov 1, 2010 at 8:37 AM | Unregistered CommenterGrantB

I hope Chritopher Booker is sent this. It would certainly give more powere to his elbow!

Nov 1, 2010 at 9:00 AM | Unregistered CommenterTony Windsor

Don Pablo.

Exactly. Using "output" from wind generation is just as misleading as using "capacity".

So the actual number that represents the contribution wind generation has made to meeting energy needs in the UK is some way short of 10%.

Nov 1, 2010 at 9:13 AM | Unregistered CommenterGeckko

@Rob Schneider

Rob, Have a look at the national grid pages, including:

and the table linked therein.

Nov 1, 2010 at 10:48 AM | Unregistered CommenterCumbrian Lad

Your numbers look pretty good to me. They agree very well with other numbers I've seen (sorry, don't recall where) which suggest about 8-10% as realistic. I think some of it was in recent discussions in a thread at The Air Vent, but I might be wrong. There were certainly several links to info there.
What was interesting in that thread was that the strong wind power proponents were completely uninterested and indeed unable to even fathom the economic or indeed technical arguments against. For them, it was enough that power COULD be generated from wind. That meant that we should embrace it and deploy it as widely as possible, even to the extent of wind baseload power.
This was achieved by erecting 8-10 widely geographically dispersed windfarms to achieve a 'reliable' output equivalent to one.....

Nov 1, 2010 at 11:20 AM | Unregistered CommenterChuckles

@ Cumbrian Lad

Perfect. Not sure how I missed that one. Munging the data into my data model right now. Thanks.

Nov 1, 2010 at 1:12 PM | Unregistered CommenterRob Schneider

In all of this has anyone bothered to calculate the ACTUAL COST per MWH of electricity generated by these windmills? That means including subsidies, required "backup" generation, lost of land values (would you buy a house near to a farm?) etc. etc. You know, the sort of thing a responsible manager of a corporation used to do?

Nov 1, 2010 at 1:23 PM | Unregistered CommenterDon Pablo de la Sierra

The energy statistics section on the Decc web site publishes the information on installed capacity and actual generation from renewable sources, which suggest that for onshore wind the generation is in the range 20-25% of installed capacity.

table DUKES 7.4 on

Nov 1, 2010 at 1:44 PM | Unregistered CommenterJK

Don: The answer is no. It is one thing we complain to the government about - namely that they have signed up to renewable energy targets without doing any engineering or economic evaluation. It has all been done because environmentalists say we can do it - it is pure politics based on spin.

Nov 1, 2010 at 3:05 PM | Unregistered CommenterPhillip Bratby


Good catch. I saw this table earlier today and didn't pick up immediately on the discrepancy. I did write to DECC at the contact email to find out if the source data for their summary tables was available anywhere and I'm told it is not.

However, your query of course got me looking deeper. See for more details, but here is a summary of what I found so far.

: DECC say in Note 7 in that spreadsheet that "Actual generation figures are given where available, but otherwise are estimated using a typical load factor or the design load factor, where known." Therefore, actual generation data from National Grid is probably more reliable.
: That being said there are still big as yet unexplained differences.
: DECC source data is not available and I've not yet discovered how to tell how much of their number for generation in 2009 is estimated vs. actual.

Since the two numbers for mean power in 2009 for wind are different by 2-3 times, more checking is required. Perhaps I've done my arithmetic wrong.

Nov 1, 2010 at 3:35 PM | Unregistered CommenterRob Schneider

There's some comment on long term wind trends here that again raise questions about an energy policy that relies on wind, plus land use changes and their effect on climate

A study published on 17 October 2010 in the journal Nature Geoscience shows that over the past three decades, surface wind speeds seem to have noticeably decreased in several regions of the world..

Nov 1, 2010 at 4:09 PM | Unregistered CommenterAtomic Hairdryer

I suppose one shouldn't be surprised if the response from DECC is that they can't supply the source data, that would after all require a certain effort on behalf of the staff. Since however the figures they present are a formal government publication, and presumably used to inform policy decisions one would be tempted to push them harder for it. (FOI?) Either they can back it up with data, or they can''t in which case they should explain why.

Nov 1, 2010 at 4:10 PM | Unregistered CommenterCumbrian Lad

Great post.I recommend John Etherington's book The Windfarm Scam as an introduction to this subject, and it appears to be even worse than he thought.
The energy policies of this government backed by almost all politicians are the biggest threat our country faces ( in particular windmills) even more than terrorism. ( Not as bad, perhaps, as the return of McCavity Brown to the treasury ).
It would be very interesting to know the actual output from all windmills during the cold windless snap last week and, in particular, the new offshore wind farm recently opened with much publicity.
If and when Rob S. finishes his analysis a simplified, ie for a ten year old, easily read version should be sent to all MPs. I, for one, would be happy to make a contribution to help with costs and I would not be surprised if other readers felt the same.

Nov 1, 2010 at 5:12 PM | Unregistered CommenterG.Watkins

Early cultures used to erect structures on hilltops, or looking out to sea, and then worship them as Gods. Their arguments were that if they failed to do so the the World would end in fiery furnace..or possibly the Sun would cease rising in the morning.

The key attribute was that such statues were of almost no practical value, consumed vast quantities of hard-won resources and diverted all their intellectual and technological resources from solving actual real urgent problems.

I always sleep better in my bed when I think of exactly how far we have advanced as a civilisation from those poor misguided 'primitive savages'. ;-)

Nov 1, 2010 at 7:51 PM | Unregistered CommenterLatimer Alder

I'm with G.Watkins. Etherington's book was an eye-opener for me.

And a quick to read summary for all MPs - professionally produced, but so that they could absorb it all in only five or ten minutes would be a great idea. Happy to help. Contact me via the Bish.of he;s willing to act as an intermediary.

Nov 1, 2010 at 7:55 PM | Unregistered CommenterLatimer Alder

As soon as t'wife has finished with the paper, I'll find the articlw where one wind farmer is objecting to another "stealing his wind"

Nov 1, 2010 at 8:21 PM | Unregistered CommenterAdam Gallon

Adam Gallon, that is an unfair claim. I'm sure that a properly executed search warrant on the alledged wind thief would fail to find any wind in his possession.

Nov 2, 2010 at 6:19 AM | Unregistered CommenterJantar


Apologies for posting this here as well as at your blog, but it may be of interest to BH readers too.

I looked into the apparent shortfall in installed capacity and the amount of wind power available to National Grid some time ago. Much of it seems to be explained by NG seeing a significant proportion of installed wind capacity as a reduction in demand. See “Measuring the Wind” at

The figures for metered capacity available to the Grid has changed since I wrote that piece. It now stands at 2430 MW. See:

Nov 2, 2010 at 10:28 AM | Unregistered CommenterHG

Adam Gallon

Was t'wife reading this?,1518,480327,00.html

Nov 2, 2010 at 10:55 AM | Unregistered CommenterDreadnought

After Christina Rossetti:

Who can own the wind?
Neither I nor you.
But businessmen in Germany
Have lately claimed they do.
Who can steal the wind?
Neither you nor I.
But businessmen in Germany
Will sue you if you try.

Nov 2, 2010 at 11:29 AM | Unregistered CommenterDreadnought


Thanks! This will take some time to unravel, I think.

Nov 2, 2010 at 12:19 PM | Unregistered CommenterRob Schneider

The Thanet wind farm was predicted by the manufacturers to be 36% CF but it'll probably be 31%.

I would expect the UK average, land and offshore, to be about 27%.

Dec 2, 2010 at 2:42 PM | Unregistered CommenterAlexander Davidson

PostPost a New Comment

Enter your information below to add a new comment.

My response is on my own website »
Author Email (optional):
Author URL (optional):
Some HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>