Tag Archives: Fallacy by omission

Do wind and solar “complement” each other during winter?

The second fact check of the “factchecker energy” of SER is titled: Is there a future for solar energy in the Netherlands?. Although the author of this fact check admits that solar energy only has a very tiny share (0.1% of the energy consumption) and it needs to be balanced by other flexible energy sources, he is very optimistic about the future. His “fact” check seem to rely on future developments related to solar energy.

As a whole, it seems a quite bland and overly optimistic fact check, but there was one statement that caught my attention (translated from Dutch, my emphasis):

There is a factor of ten difference between summer and winter output of solar panels. What the share of solar power in the electricity mix will be, will depend to a large extent on the developments in electricity storage (for short and longer periods) and of the expansion of the electricity connections with other countries. Wind power and solar energy complement each other in that respect: the supply of wind power is higher in the winter when the supply of solar energy is lower.

That is an interesting statement. Apparently wind energy produces more power in winter and this compensates for the loss of output of solar cells during the same time. I decided to have a look at the data to find out to what extent “wind complements solar”, but also the significance of this phenomenon in a continuous working grid.

Continue reading

Breaking windows for a better economy?

Factchecker energie SER

Last week, I came across the “factchecker energie” from the Energy Agreement of the SER (Social Economic Council, the Netherlands). The goal of this fact checker is to give, ahem, “objective information about sustainable energy to civilians and companies”, because the “heated discussions on this subject are not always based on facts”.

Nice to hear that they care about the facts, but it is a pity that, as usual, only the facts from one side are provided.

This post will be about the first fact check from a series of (currently) five and is called Episode 1: The Energy Agreement is good for the economy (attention, Dutch ahead). This is how it starts (translated from Dutch):

What are actually the benefits of the Energy Agreement?
The Energy Agreement contributes to an affordable, clean energy supply for the Netherlands. […]

Continue reading

What’s another year?

It was to be expected: Wadhams has renewed his claims of an ice-free Arctic. The Guardian published on August 21 an article with the catchy title ‘Next year or the year after, the Arctic will be free of ice’.

In a previous post, I already compiled quite a list of predictions of an ice free Arctic. At that time (June) it was rather unlikely that this year we would see an ice-free Arctic. But no problem, 2017 was already on the radar back then. When looking at the statements in the Guardian article, now it will be next year (summer 2017) or the year after that (summer 2018).

Another year to add to the list.

There was more in the article that caught my attention. Like the first paragraph of an interview with Wadhams:

Continue reading

Some more background, insight, context … yes please

Just one week ago I watched an interesting discussion on Reyers Laat (a talk show of the Flemish television). It wasn’t climate related, it was actually about the terroristic attacks in Paris. Part of the discussion was the role of the media in the current fear. By focusing on the negative things the media gives the impression that we live in a worrisome world.

The host invited among others the editor-in-chief of the VRT television news, Björn Soenens. He stated that the media should play another role in society. The media should privide a framework, give more background, insight, context. In that way the public would be better prepared to judge such situations. That is a noble mission, but seeing the reaction of one participant in the discussion showed me not everybody believed him. I wasn’t impressed either. I knew that the VRT news wasn’t exactly an example of these aspirations. His news program got mentioned several times in this blog for its bias in climate communication.

Just take a look at some examples from his own organization. This is how the global temperatures of 2014 were presented in the online version of the vrt news:2014 was the warmest year worldwide since 1880 (Dutch) and Worldwide heat records can’t be a coincidence anymore (Dutch).

Basically they only report on the NASA and NOAA datasets and from this they concluded that 2014 is the warmest year.

This is what they didn’t explain:

Continue reading

Warning: may contain traces of science

The Marcott Hockey stick

The Marcott Hockey stick

Almost two months ago, when this blog was just starting and the first few posts were put online, the media breathlessly reported the publication of a new paper by Marcott, Shakun, Clark and Mix. In the paper there was a graph that was quite impressive. It showed the temperatures of roughly the last 11,300 years (the Holocene). This graph showed an increase of temperatures until 10,000 years ago, then a plateau that lasted about 5,000 years, then a gradual decrease of the temperatures until the last hundred years or so, when temperatures suddenly went completely through the roof.

To be honest, I was not really impressed, I remembered well The Hockey Stick and the current paper showed something rather similar, but over a larger time frame. It was presented in the media as independent research that came to the same conclusion. There was a difference though: the Marcott paper was well documented. This would make it easier for skeptical souls to analyze the whole thing.

Some of the claims that were made in this press release (my bold):

The analysis reveals that the planet today is warmer than it’s been during 70 to 80 percent of the last 11,300 years.

What that history shows, the researchers say, is that during the last 5,000 years, the Earth on average cooled about 1.3 degrees Fahrenheit–until the last 100 years, when it warmed about 1.3 degrees F.

“What is most troubling,” Clark says, “is that this warming will be significantly greater than at any time during the past 11,300 years“.

Wow, these are heavy claims. The 11,300 years statement was repeated no less than six times throughout the press release. They surely wanted to rub this in! This was the crux of the press release. Leave this out and it would be unremarkable and rather bland press release, nothing newsworthy.

When the press release broke out I didn’t care about it too much. I had the impression that this was a statistical construct, just as the original hockey stick was. Other people with much more knowledge of statistics probably would dissect the whole thing to pieces. Nothing for me to worry about. For those who want to have more background on how this hockey stick was crafted statistically, this series at ClimateAudit has the analysis of Stephen McIntyre in all its finest details. I will not go in too much details, I only will mention a few things that struck me in passing by.

It was as expected: in the underlying data there was no uptick. Also, Shaun Marcott used the same data in his thesis and the corresponding graph showed no uptick either. What changed in the meanwhile so that with the same data an uptick would surface?

McIntyre found that the proxy data were re-dated et voilà: after the re-dating suddenly there was an uptick. So: no re-date → no uptick. Re-date → uptick. The uptick seemed dependent on the re-dating of the proxy data.

When the paper came more and more under fire, a FAQ was published on the realclimate website. It is a very interesting read. This is what it said about the uptick (my bold):

Our global paleotemperature reconstruction includes a so-called “uptick” in temperatures during the 20th-century. However, in the paper we make the point that this particular feature is of shorter duration than the inherent smoothing in our statistical averaging procedure, and that it is based on only a few available paleo-reconstructions of the type we used. Thus, the 20th century portion of our paleotemperature stack is not statistically robust, cannot be considered representative of global temperature changes, and therefore is not the basis of any of our conclusions.


Any small “upticks” or “downticks” in temperature that last less than several hundred years in our compilation of paleoclimate data are probably not robust, as stated in the paper.

and later in the answers on questions of the readers:

The most recent points are affected strongly by proxy dropout and so their exact behavior is not robust.


They specifically state that this reconstruction is not going to be useful for the recent period – there are many more sources of data for that which are not used here – not least the instrumental record

That’s puzzling. In the press release we were repeatedly told that the temperatures of the last 100 years were significant higher than over the last 11,300 years and now we get to hear that:

  • If there was a warming trend in another part of the Holocene similar to that of the last hundred years, this method wouldn’t even be able to detect it.
  • The last 100 years of the graph is not robust and one cannot derive anything conclusive from it.
  • The conclusion in their paper is stated differently than that of the press release. In the paper they state that the last hundred years are not robust and therefor are not included in any of their conclusions. But they “forgot” to mention this fact in the press release and shouted out the relevance of this last hundred years with certainty. This is very misleading. It tricks readers of the press release (it will be read by much more people than the paper) into believing the paper’s conclusion is that the last hundred years are definitely warmer, when this wasn’t the conclusion at all.
  • It was stated that although the reconstruction was not useful for the recent period, other sources like the instrumental record are. But this is not the issue here. The reconstruction in the paper has an uptick, the press release refers several times to the same uptick. It is being emphasized in the media as independent confirmation of other upticks. Yet it is not robust and not useful for the period it is told it is significant for. If this is true, then this paper is no independent confirmation of the 20th century warming and it should not be presented as such. If they compared to other sources like the instrumental record in stead of the Marcott uptick, fine, but then they should have said so in the press release. They did not and even emphasized the “finding” of the paper as if it was significant.

To continue on this last point: the final date of the reconstruction is 1940. That doesn’t make much sense. If this is really the case, they found an uptick starting 100 years before 1940. But CO2 only got traction in the 1950s, so if the last proxies were (re)dated 1940 and they really found an increase, they couldn’t possibly attribute this to anthropogenic CO2. This means that they found an unprecedented huge natural temperature increase from the end of the Little Ice Age until the 1940s! That is exactly the opposite what they suggested in the press release. Which blows their statement (about CO2)…

It’s the only variable that can best explain the rapid increase in global temperatures.

…straight out the water.

Apparently they aimed for maximum shock effect. As a layman, after looking at this, I have many questions. How trustworthy is/are the author(s) of the press release? Why the huge disconnect between the conclusion of the paper and the statements of the press release? What is it that they really were trying to communicate here? Obviously not the science.

(Over)blowing in the wind


How can one not like free wind energy? It looks that simple. The wind is plentiful and blows free for everybody. Many green minded people naively believe the idea. Also I previously assumed that when the rotors of a wind mill were turning they were saving energy, because the electricity they produced shouldn’t be produced anymore by a fossil fuel power plant somewhere else. Boy was I wrong!

An example

When looking at the page of the C-Power I found the following statement concerning the first Belgian offshore wind farm:

The capacity of the completed wind farm will be 325.2 MW, enough to provide power to 600,000 inhabitants

This is not an isolated case of reporting it this way. Every time for example the mainstream media reports on wind energy, this kind of statement is given. Sometimes they give it in number of people or in “households” or “homes” that supposedly benefit from the windmill(s).

It is a nice statement on its own, but when digging deeper things don’t seem to add up well. Let’s see about this in more detail. They give more detailed information about this farm on another page on their website:

The wind farm consists of 54 turbines with an installed capacity of 325.2 MW

According to calculations by C-Power, based on over 1.2 million historic wind measurements on the coast since 1986, the wind turbines will run for 8,440 hours per year, being 96% of the time.
The equivalent number of hours when the wind turbines are running at full power (equivalent full load hours) has been calculated to be approximately 3,300hrs/year.

That’s 38% of the time, which is a normal figure for offshore turbines.

Digging deeper

This gives me the information to reconstruct the calculation of the statement. Just a quick calculation. The 54 turbines are erected in three phases and with two different capacities.

Phase Number Capacity (MW) Total capacity MWh
I 6 5 30 99,000
II – III 48 6.15 295.2 974,160
Total 1,073,160

In kWh this will be per person per year: 1,073,160,000 kWh / 600,000 = 1,788.6 kWh. That is a plausible average number in Belgium, so at first glance the statement seems to hold very well.

So, what is the problem then? They will produce 1 TWh in a year (what C-Power acknowledges) and this will be equivalent to the yearly use of about 600,000 people (what the Thornton bank-site said and what the calculation seems to confirm). Yes, that’s all true in theory, but in practice it is a completely different story.

The power produced by these windmills will obviously not really go to a group of 600,000 people. There are no power lines from the farm to their houses. The reality is that the power will be put on the national grid and such an amount of electricity can be used by around 600,000 people with an average power consumption of 1,788 kWh per year. This is a very important difference. The first statement seems to imply that the output of these turbines can fully satisfy the power needs of those 600,000 people. It is not.

If this really was the case, they would have:

  • complete blackouts during the equivalent of 4% of the time (about 15 days per year)
  • a varying amount of power during an equivalent of 96% of the time (about 350 days per year)

Unless they get their power also from other sources.

Indeed, this power is not produced constantly. According to the specifications of the turbines, below the wind speed of 3.5 m/s the turbine doesn’t produce anything. The same above 30 m/s averaged over 10 minutes or 35 m/s peak.
Below about 14 m/s the turbine produces only a part of the installed capacity.

The company estimated the working time of the turbine to 96% according to their wind measurements. But this doesn’t take into account the time the turbine stands still because of defects or maintenance. So those figures are again too rosy. The nice 39% load factor is only for brand new turbines, but according to data of the offshore wind farms in Denmark, the load factor declines over time (in case of Denmark from 45% to less than 15% at 10 years of age). That is 1/3 of the initial value left! There are several reasons for this. There is the wear and tear of the turbines and the blades in the humid, salty sea air. But also the turbines experience more breakdowns, need more maintenance and will take longer to put back on line. If the Denmark data is correct, the capacity could decline to one third after 10 years, which means the farm will only cater for “about 200,000 people” anymore.

Wind energy is intermittent. It is not very suitable for power production which needs a reliable output. Power consumption has a certain pattern over a day, but power generation follows the pattern of the wind and is not necessarily in accordance with actual power consumption. If we really want to rely on wind energy, we will need a backup generator that fills in when necessary, which means such a fast reacting generator will turn mostly at suboptimal speed and use more resources than when running at optimal speed.

This is the little dirty secret of wind energy: when we want to rely on wind energy as a constant power source, we need backup plants that run at a fraction of optimal capacity than when it would be if the wind farm was not there. Or put it in another way: even when wind turbines are working optimal, the backup system is still on stand by AND uses (fossil fuel) resources.

What did I learn?

My previous assumption that windmills were saving us fossil fuel seems to be unwarranted. This assumption was fed by waves of smooth stories from which one side is completely omitted, as the one above. Although the installed capacity of the generators and the wind data (the nice data) were correctly brought, the data of the maintenance, capacity decline and backup needs (the inconvenient data) were completely ignored. When adding this information, it paints a completely different picture than the theoretically capacity story.

An argument that omits relevant evidence appears stronger than it is. No wonder this inconvenient side of the story is hardly been told. No wonder the public at large still has false expectations about wind energy.