Is there Something (Else) Wrong with Wind Power?

We all know wind power is intermittent. I thought I would take a look at how predictable windpower intermittency is and how accurate wind power output predictions are.

In the process I think I have tripped over a new issue regarding wind generation (but more on that later).

The bmreports site (HERE) has a section on wind generation and shows a graph of an original output prediction, a more recent and accurate revised prediction and also the actual out-turn.

The original forecast value is done 41 hours before the start of the forecasted day. The revised forecast is done 4 hours before the start of the forecasted day. The predictions use weather forecast data for the known wind farm locations and factor in a range of other parameters. These are sophisticated predictions and are probably as good as they get.

Here is a few example snap shots taken in the last month from the bmreports site.

But as well as this continuously updated graph, bmreports also publish the same 3 day data as an xml file. I've collected the xml files for one month. (Annoyingly I missed two days so these have been left out. But even so I think this is quite a good data set.)

Above is a graph of this data showing the final revised prediction done 4 hours before the start of the predicted day (red) and the final out-turn (blue).

(I've left out the original prediction as for obvious reasons, it was more in error of the final out-turn and so added little to the graph). Note: Actual metered capacity is actually 8972MW so the graph is unduly kind stopping at 8000.)

The first thing that can be seen is that the out-turn is often (not occasionally) in significant variance with the predictions. The graphs may be the same shape but the values at any one point in time are often significantly different. Clearly, any system with a large wind component that relied completely on even a near term forecast (and without spinning reserve) would soon end up in deep trouble.

So whatever the pro-wind zealots preach on Twitter, the problem with lack of wind power predictability has not gone away. Neither has its intermittency.

But potentially the example bmreports graphs (as well as mine) also show another problem. 

Notice in the above graphs how on the occasions the wind output rises above about 30% capacity (3000MW), during the rise, the out-turn lags the predictions and the maximum out-turn is significantly less than either of the predictions. 

It is as if a large proportion of wind turbines exposed to a rising wind and high wind periods are being feathered (or throttled back) for some reason during these periods.

At lower wind speeds there are still periods of great discrepancy between prediction and output but the tracking between prediction and output does appear more coherent. (Remember this forecast was done 4 hours before start of predicted day!)

Wind energy companies only get paid when they are generating. So why would they throttle back their turbines in high winds?

And the answer to that I believe is good old repair and maintenance.

For almost any machine, if you run it lightly it lasts longer. Take a car. The harder you drive a car the more wear and tear it suffers. Just about all rotating machinery obey this simple rule – including wind turbines.

We know that there is a severe generic problem with wind turbine gearbox reliability. (See This Post - The Ghost in the Gearbox and Post - More Ghosts in the Gearbox )

I would suspect that it has been found that if the loading on a wind turbine gets above a certain value the wear rate and maintenance/repair cost will be far more than the return from the extra energy generation.

So maybe operators are unilaterally and quietly deciding that when the wind gets too changeable or too strong, the turbines will be run at reduced output compared to what they are supposed to be capable of.

Wind turbines are capital intensive. If you suffer a catastrophic failure you will ruin the huge and guaranteed profit (subsidy included) your turbines can make. Do it too many times and you may end up going bust. Better to ignore the whole reasoning, propaganda and hype associated with why the thing was built in the first place and go for the low hanging fruit.

Remember most windfarms have a 25 year subsidy regime locked in place. It's a nice little earner. Operators are going to do whatever it takes to maximise the financial gain over this period and if that includes reducing output to make their gearboxes and other expensive components last a bit longer then they will do it. The abatement of Carbon Dioxide can go to hell.

This, of course, makes an even bigger mockery of the often hyped “Installed Capacity” figure than it already is. It also shows how the unreliability of these machines impacts the supposed reason they were built.

It means that wind power is perhaps even more useless and under-achieving than first thought.

I cannot prove the operators are intentionally throttling back their turbines to reduce their maintenance bills. 

But I bet I'm right.

Wind Turbines: More Ghosts in the Gearbox

There is a wall of silence from the wind industry regarding wind turbine reliability. But once in a while data seeps out through the wall to the general public. A little bit of new seepage has just come to my notice.

The last time I blogged about wind turbine reliability was after I had come across an obscure department within the USA government National Renewable Energy Laboratory (NREL) called the Gearbox Reliability Collective (GRC). The purpose of this U.S. government sponsored department is to address the appalling and largely hidden reliability problems with wind turbines, particularly gearboxes.

The GRC has their own website here: http://www.nrel.gov/wind/grc/ 

My first post on the GRC is On This Link 

The GRC is not alone. Clearly there are several European agencies and groups working on this problem too. Unfortunately information on them is very obscure. I am unaware of any public access to their data other than when it is mentioned by the GRC.

What has just caught my attention is a 2013 paper from the GRC. The  paper is titled: 

Report on Wind Turbine Subsystem Reliability ─ A Survey of Various Databases.

The paper is on this link: http://www.nrel.gov/docs/fy13osti/59111.pdf

If you look at the linked document above you will find a survey of many wind turbine failure databases held in Europe and the USA.

As far as I can ascertain there is no public access to any of this data except to that presented in this paper. If I am wrong I would be grateful for any links – I have found none.

The figures from Europe in this survey stop short of fully quantifying failure rates. They do though hint at a failure rate increase for larger turbines and crucially, also for direct drive turbines.

We also have the USA data in the same document. Some of the USA data goes right up to 2013. This American data is far more open and definitive. It gives failure rates for all major components not just the gearboxes.

Here is the table (see page 31) relating to expected annual gearbox and generator failure rates for on-shore turbines.

The NREL reckons for gearboxes this averages out at 5% per year for the first ten years. Notice that in year 5 it hits 10%. 

Whatever way you cut it statistically around about 50% of turbines will suffer a gearbox failure within 10 years. Remember this is for properly maintained, serviced and generally “looked after” turbines.

But also remember – that is ONLY the gearbox. The generator is “slightly” more reliable coming out at an average failure rate of 3.5% per year or 35% over ten years.

So for an onshore turbine in the USA the chances of a properly serviced and maintained turbine failing due to gearbox or generator issues within 10 years is 85%.

If you include the other potential failure areas (say the blades - failure rate quoted at 2% per annum) then statistically, it is almost surely that a properly maintained and serviced wind turbine will suffer a major failure within 10 years. It looks like most failures will occur in year 5 or 7.

All rotating machinery can (and will) break down. But wind turbines are operating in a chaotically changing and hostile environment (offshore turbines even more so). A gas plant by comparison is operating in a closely controlled and regulated environment. So per Megawatt-Hour, the wind turbine will require much more maintenance.

The energy return from a wind turbine is simply inadequate to pay for the very high demands placed on maintenance and repair. As the machine gets older more maintenance and repair will be required. Eventually the point will be reached (7-10 years?) where the maintenance/repair bills exceed the returns.

The often hyped 25 year life span for a wind turbine would appear to be hopelessly optimistic.

Currently the only way round this problem is to hugely increase the price of the electricity generated by the machine from day one. This is essentially what the current government subsidies do.

But one day the subsidies will have to fall. When this happens, or as the turbines get older and more unreliable, the wind farms will end up being be sold on - and on.

The new owners will be ever more dubious organisations. Eventually the turbines will be run until they suffer the final major failure that renders the turbine beyond economic repair. Then they will be abandoned.

When the last one fails and the payments stop, the bailiffs will arrive to claim the “guaranteed” decommissioning fund. But by then the main company office will be a post box in Belize and the decommissioning fund will be long gone.

Remember almost all of the data in the above paper is for on-shore turbines.

When you go offshore the maintainability and reliability falls off a cliff. The consequent subsidies sky-rocket.

But more on that in another post.

Yet Another Damning Wind Power Report

Another detailed and peer reviewed report on the effectiveness of wind power has been recently published by the Adam Smith Institute. (h/t to @strumcrazy at twitter)

The report has been produced by an Engineer with a long history in the power generation industry including pumped hydro. It's data is unimpeachable and is based on reliable wind speed data obtained from airport meteorology stations. 

The summary is brutally factual and casts a long black shadow over all the vacuous hype over wind power recently seen in the UK.

The document is available Here

Here are some of those brutal facts. (but by no means all)

Over one year the UK model showed:

Power exceeds 90% of available power for only 17 hours

Power exceeds 80% of available power for 163 hours

Power is below 20% of available power for 3,448 hours (20 weeks)

Power is below 10% of available power for 1,519 hours (9 weeks)

The most common output of the entire theoretical 10GW UK wind turbine fleet is 800MW or 8%.

The probability that the wind fleet will produce full output is vanishingly small.

Long gaps in significant wind production occur in all seasons.

To cover these gaps would need energy storage equivalent to 15 Dinorwig size plants (incidentally Dinorwig cost £1.5Bn. It is also not far short of being geologically unique in the UK – Billo)

As we cannot build 15 Dinorwig's in the UK we could do what the German Energiewende is doing and build dirty Lignite burning coal plant instead as backup. ( that is not a serious suggestion by the way)

Of course, if this was just one paper, however scrupulously prepared, we may well be entitled to a level of skepticism about its findings.

But this is very far from the first.

In 2010 The famous Nature conservancy charity “The John Muir Trust” commissioned a report by Stuart Young Consulting. The John Muir Trust webpage on this report (with link) is Here The actual Paper on its own is Here

Stuart Young Consulting (using actual generation data) found the following:

Over a two year period (2008-10) The UK wind turbine fleet was:

• below 20% of capacity more than half the time
• below 10% of capacity over one third of the time
• below 2.5% capacity for the equivalent of one day in twelve
• below 1.25% capacity for the equivalent of just under one day a month

Again that is just a subset of the dismal performance they found.

Does it stop there? – No. Here are a few more reports:

Reports by:

Mercados Consulting – Powerful Targets (2012 originally suppressed by UK govt.) Link Here

Civitas – The Folly of Windpower (2012) Link Here

Prof. G Hughs Edinburgh University - Why Is Wind Power So Expensive? (2012) Link Here

The Royal Academy of Engineers – The Cost of Generating Electricity (2004) Link Here

Note that the oldest of these reports dates back some 10 years. This is not new knowledge but it has been comprehensively buried and suppressed by the wind industry and their political backers.

But as the saying goes: 

The truth will out.

Wind Turbines: The Ghost in the Gearbox

I first came across this shocking industrial wind turbine (IWT) gearbox problem some time back and posted about it (Here) and originally (Here). The basis of these posts was this article (Here)

This long running problem is so serious that since 2007, the US Government has been coordinating research into it through the NREL. (More on that further down.)

By the looks of it nothing has got better, although there is a lot of industry spin claiming the fix is just over the hill. Some of it quite recent  (See Here)

So what is the problem and why is it kept so quiet?

Industrial Wind turbines (IWT's) have a generic, long standing and apparently intractible problem with gearbox reliability.

Many gearboxes need a rebuild within 5 -7 years instead of lasting 25 years as designed. Many suffer catastrophic failure within the 5-7 period or even earlier. Depending on the age of the turbine, a gear box failure may effectively write it off. Even when repaired, these gearbox failures are highly expensive and often take out the turbine for months.

Replacing the gearbox adds massively to the overall cost of the IWT. Manufacturers increase the cost to cover warranty repairs in the first 5 years. When out of warranty, the cost of a maintenance contract sky-rockets, eventually to a point where the operation of the IWT becomes untenable.

Why does this matter? After all it is the operators/manufacturers problem isn't it?

It matters because IWT's are capital intensive. That means that most of their operating cost is mostly soaked up in purchasing the thing - and maintaining it. If the IWT has a much shorter life (or a much higher maintenance cost) and so produces less money than anticipated, their ability to ever live without massive government subsidy becomes an even bigger illusion than it already is.

So, you may say, "It is only a technical glitch ...it 'll all come right in the end."

Well, maybe. But first of all this is a glitch that has lasted since the 1980's

Unfortunately the evidence suggests that nobody actually knows what to fix yet let alone how too fix it. So possibly the answer is - maybe not.

We need to get an idea of how bad this problem is but for obvious reasons the wind industry isn't telling and they are certainly not releasing any meaningful figures

But there are a number of alarming markers out there.

The  US Government (in association with the wind industry) formed a little known group called the "Gearbox Reliability Collaborative" (GRC) (See Here) ** The GRC is no less than a section of the USA government NREL. (That National Renewable Energy Laboratory).

** [2017 - This website is no longer publicly available and returns a 404. The advertising brochure for the GRC is still publicly available at This Link. It appears the research papers linked to below are also still available]

In other words the problem is so bad the US Government is having to tackle the problem.

The leading sentence on the GRC website blandly states...
[quote]
Premature gearbox failures have a significant impact on the cost of wind farm operations.
[unquote]

To quote from the latest finding report from GRC testing...(Here)
[quote]
Despite reasonable adherence to these accepted design practices, many wind turbine gearboxes do not achieve their design life goals of 20 years—most systems still require significant repair or overhaul well before the intended life is reached. 
[unquote]

These guys in the NRC are (to put it mildly) clever people. But they have been at this since 2007 and so far they are still, by all appearances, quantifying the problem. In otherwords on a scale of ten, the intractibility of the gearbox issue probably rates a nine.

The NREL does not allocate such significant resources lightly. This is a bad problem.

The GRC are trying to build a failure database as well as running a series of tests on prototype gearboxes. Unfortunately this failure database is not for public consumption and is subject to a strict NDA so we will probably never know the full facts.

Manufacturing members of the GRC can (and mostly do) remain anonymous. One exception is Vestas. While I have little time for any wind industry company at least Vestas appear to be willing to stand up and be identified rather than just pretend their is no problem like the rest.

Of course, while we do not have full access to the database we do have some access to data held within it from the research papers published by GRC

For example, from an early sample set from 2010 and This Paper  covering 37 failures we have this:

Notice that while this early table covers 37 failures there were many more problems found in the strip downs. It looks like the problem is poorly localised and is probably caused by a number of different issues.

So what is the point of this post?

Simply to show that the current fleet of IWTs (yes - whole fleet ) are really not fit for a production environment. They are still suffering intractible and major operational problems and are highly unlikely to ever be able to operate without a huge government subsidy. To suggest they have a lifespan of 25 years is laughable.

This is bad enough for land based turbines.

But anyone who suggests that we can successfully and economically place these things out in the North Sea and English Channel for long term energy generation, is in need of medication.

Wind Turbine Reliability and that Elephant Again

A detailed  analysis of the reliability and life span of on-shore and off-shore turbines has been produced by Professor Hughes of Edinburgh University. Because his findings are so controversial the paper has been independently statistically verified.

Far from having a lifespan of 25 years as promoted by the wind industry, it looks like the lifespan will be more like 10-15 years. Furthermore, during that 15 year lifespan, the capacity factor will progressively diminish.

Professor Hughes paper is Here
The Telegraph has also produced an article on this Here.

Professor Hughes suggests that even the wind industry has not yet realised it has this problem. Personally I think they have known about it for years.

I first blogged about the massive ongoing gearbox reliability issue (Here) This was based on this article Here. But it is not just the gearboxes. Since then we have had the grouting failure that has affected almost all offshore turbines in Europe, with many shifting on their base (Here). But these failures are just the headlines.

Yet the wind industry are in denial. Take the  pathetic bluster from RenewablesUK in the Telegraph article.

[quote]
...so it’s very much in their interests to make sure that their turbines are maintained… to an optimum level, which includes upgrading as the technology improves. 
[unquote]

Anyone running machinery should optimally maintain it! But it will still wear out.

The question here is : What is the lifespan WHEN you optimally maintain it.

It sounds like the wind industry is back to relying on miracles. You know, something (as yet unknown) will come along that will make it all better. Don't forget wind turbines are supposed to be a mature technology. Sadly, whatever you upgrade to, you are simply not going to beat the laws of physics, and every upgrade is yet  another capital cost.

As any rotating machine ages it requires more maintenance. Eventually it reaches a stage where the machine requires so much maintenance it is classified as Beyond Economic Repair (BER). In other words, it is clapped out. This happens to ALL machinery. It happens to Jumbo jets, nuclear power stations, buses, cars AND wind turbines.

The wind industry propaganda has declared that BER for a turbine is 25 years. The truth, as proven by Prof. Hughes, is that the BER is reached in about 15 years.

Wind Turbines are capital intensive. The whole of their potential profitability is solely dictated by the total amount of energy they can produce over their life time. If their lifespan to BER is lowered then the possibility of them being profitable without an enormous subsidy decreases, especially later on in their life cycle.

You will also find that from a DECC document (Here) that current wind turbine annual maintenance costs range from £12000 to £110,000 per turbine. The amount is heavily dependant on the status of the warranty and consequently its age. As it gets older the maintenance cost sky rockets – until you reach BER.

With a decreasing capacity factor and an increasing maintenance cost over time, the money making years for a wind turbine are the first 5 years. Then its downhill all the way.

Turbines are medium term cash cows for their corporate owners. When they approach BER, either because the subsidy is cut or they blow up their second gearbox, they will be sold on. Then when the second/third/fourth company has run them into the ground they will be sold on again for scrap and  the  valuable components stripped out. Then they will be abandoned. In situ.

When the bailiffs finally turn up demanding the derelict  be cleaned up they will find that the “owner” is a post office box in Belize.
Guess who will get the final clean up bill.

Burning Wind Turbines Revisited

While I was away in pastures new, I witnessed a rare and catastrophic failure of a motor vehicle. It caught fire. Luckily nobody was hurt but the car burned with spectacular vigour. I only noticed this catastrophic failure because of the smoke and flames.

If the forlorn Vauxhall Vectra had merely lost its cambelt so allowing the pistons to punch the valves through the cylinder head, or if the car had crashed and rolled and had been left on the hard shoulder I probably would not have noticed. But in either case the catastrophic failure would have been just  just as complete.

Less than one car in a thousand in a year catches fire due to mechanical/electrical failure. But I place bets that one in a hundred cars will suffer a non fire catastrophic failure that reduces them to scrap.

So for every accidental car fire, at least ten others suffer a non fire catastrophic failure that reduces them to junk.

That got me thinking about the celebrated explosion and burning of the Scottish turbine during the high winds in December 2011. ( See Daily Mail Here )

We know that a burning turbine is a fairly rare event though it is very far from unique. We also know that there is a severe and apparently intractable generic gearbox problem (See Here) which affects almost all turbines in current use.

In Scotland during the storm one turbine burned. So how many others quietly suffered some catastrophe, but without the drama of flames and burning wreckage?

When a car catches fire it is usually related to the fuel system dumping fuel onto the hot exhaust. In Wind turbines the only flammable liquids are the lubricants.

As a result, I would suggest that, the ratio of wind turbines catching fire to those merely suffering
a catastrophic failure is smaller than the same ratio for cars. That is what I would suspect anyway. (Anyone disagree? and why?)

For cars statistically, for every one that burns more than ten others catastrophically fail without the flames.  A ration of 1:10 (worst case)

For wind turbines a ratio of 1:20 possibly 1:30 would appear to be more appropriate. Maybe it is higher, say 1:50. Who knows? (nobody is telling)

So the (excuse the pun) the burning question is:

How many turbines got quietly taken out by the storm in December 2011?

 If this were cars, from one burning car you would suspect that 10 or more would have failed.

We know from ( Here ) that these large turbines have a really severe reliability problem with their gearboxes. I would therefore suggest that 20 possibly or 30 turbines suffered catastrophoc failure due this this one severe (though not unusual) storm.

This is of course supposition, but I do not think the operators are likely to be telling us any more information soon. So this analogy is as good as any.

The final thought on this is how many turbines would we lose if we had a 1987 severity storm?

Of course in the 1987 storm and other severe storms there was a great deal of damage to the electrical supply infrastructure as well. With this insane expansion of the wind turbine fleet, we are going to end up with hundreds upon hundreds of extra miles of extra grid to maintain. A great deal of this pyloning and cabling will be cutting across our open countryside and is going to be difficult to maintain at the best of times, let alone where large sections of the grid are knocked out.

So next time you see a burning turbine remember it is just be the tip of the iceberg.

Bad Engineering and Premature Technology

Taken from "The Times" (letters to the Editor) today.....

[quote]
I am most worried by the billions of pounds being misinvested and lost as a consequence.

Look out to sea at the end of 2015 and see how many windmills are not turning and you will get my point: there are already 14,000 abandoned windmills onshore in the US.

Premature technology deployment is thoroughly bad engineering, and my taxes are subsidising it against my will and professional judgement.

Professor Michael Kelly 
Department of Engineering, University of Cambridge
[unquote]


That just about says it all really.

The Elephant In the Turbine

Sometimes when Billothewisp is reading through papers on the foolishness that is wind turbinery, he comes across a paper or article which makes him feel a bit Queasy. A bit like he has read something that is not for general consumption, but has inadvertently been put into the public domain. Something that makes old Billothewisp feel like a spy in a foreign camp.

You know - a bit like overhearing a crimmo secretly confess to a crime while the press and the cognoscenti are baying about a miscarriage of justice.

Or hearing one of "His Majesty's" entourage quietly whisper: "Yes! the King really is wearing no cloths".

Recently I had two of those almost meta-physical moments. And they were related and did not involve any cider.

The first concerned a new  piece of posh propaganda released by the zealots in Centre for Sustainable Energy (CSE).

Who are the CSE?

Yet another "charity" (and I wonder where the cash comes from.). While they are no doubt, a bona-fide charity, I don't think any-one there is going short on the pay and perks front.

Anyway, I digress. The CSE have released a document called "Common Concerns about Windpower"

It is without doubt a truly wonderful piece of propaganda.

It is so good Billothewisp awards it the Joseph Goebbels Truth Economy Award for 2011. (First Class)

To be fair, it doesn't tell many lies (although there are some) but it does vigorously, wholeheartedly, and with serious malice afore-thought, twist the truth into its own perverted little vision.

Not since some guy in the CIA described the 1975 failure in Vietnam as a "sub-optimal victory" has there been such a shiny spin put on such a dismal subject.

There is so much that is wrong in this document it is difficult to know where to start, so as Julie Andrews once said "I'll start at the very beginning" (a very good place to start).

There will, no doubt, be several posts about this as I cut my way through this "charitable work" of the CSE.

Anyway part one show us all how wonderfully greeeeeeeen the average turbine is, and how is repays its energy deficit in the wink of an eye.

In fact, according to our charitable friends at the CSE  (billothewisp assumes a straight face here) the average turbine repays its energy cost within 3 months - 6 months at the outside.

The CSE then go to tell us that in its lifetime, a turbine will return at least 20 times the energy used to manufacture it.

Now we come to the first "spy in the camp moment"

3 months x 20 = 5 years. Does a "productive" wind turbine really wear out in 5 years? Or maybe 10 years for the ones that hardly produce anything - aka The Wind Turbine in Reading

Or maybe the figures are..... (dare I say it) Wrong.

Oh, I can hear the indignation.
I can see the trembling bottom lips.
The tears of of outrage welling up in the average windies eyes.

That was "at least 20 times". At least means more than. 5 years is the minimum.

Hmmm let us have a comparison.

I buy a new car. It will be good for at least 100,000 miles. Most though won't get to 120,000 let alone 200,000. 300,000 will be a freak exception.

As a comparison it would (sort of) indicate that hardly any turbines (if any) will ever make it to the much vaunted 20 -25 year life span.

But that of course is just an old engineer making a dodgy comparison.

How about some inside facts?

Here my grubby little Englanders we come to the second document and the second "spy in the camp" moment.

This second article was so well named  I stole the title for this post. It is available Here.

The document is the June 2010 cover story for the August journal: "TRIBOLOGY & LUBRICATION TECHNOLOGY" The article is obviously written by an "enthusiast" i.e. one who thinks wind turbinery can do no wrong.

But the basis of the article, which the author  does comprehensively expound on, is that the gear box blows up every (wait for it) 5 to 7 years. Actually, although it is written by an enthusiast, the article lacks the self serving  deceit of the CSE document. The guy is obviously an engineer. He just needs treatment.

Here is a cut and paste of highlighted paragraphs...

Oh Dear! but then... (Ugh!) there is this....

The author informs us that gear box reliability has been a known problem for well over ten years, without yet even coming close to being solved.

So today the problem of gearbox reliability is NOT solved.

One day it maybe solved. One day. but not today. Maybe tomorrow, maybe never.

We are building these things and plan forcing the Grid to rely on them, even though have a known ( and terrible) reliability issue.

Let us go back to the transport analogy.

Say you operated a a fleet of lorries. Would you replace your existing old but "known to work" fleet with a fleet of shiny new lorries which were known to have a massive reliability problem?

If the salesman came up and said to you, "Oh that'll (probably) be solved in a few years" would whip out your cheque book or kick him out of the door?

Not only are these things ugly, inefficient, intermittent and uneconomic. they are also hideously unreliable.

Other than that (besides the health issues, the subsidy and landscaper damage) I suppose they are (to paraphrase the CIA propagandist) sub-optimally OK