Author Archives: trustyetverify

The last week of July, a “typical” week of the year?

The paper on the 10% increase of lithium-ion battery life as a result of operating in a vehicle-to-grid (see previous post) is an interesting read. I was initially fascinated by the validation of their battery degradation model, but the actual result came from the integration of that model in a smart grid algorithm. This algorithm was then used in a simulation of load balancing of a building by means of electric cars and resulted in the 10% increase of battery-life figure.

That number is therefor not obtained by measuring the battery degradation in reality, it is the outcome of a mathematical model. Personally, I don’t have a problem with models and this particular model seems to have potential (the battery degradation part is validated). Models are useful for sure, but that doesn’t mean they are necessarily right. It depends for example on the data that goes in the model and the assumptions that are made. It seems that this is where it went wrong in this simulation.

The data that was fed to the algorithm came among other things from an actual building (the International Digital Laboratory). This is the description of that building:

The International Digital Laboratory (IDL) is four story office building located on the University of Warwick campus near Coventry. The University is situated in the centre of England, adjacent to the city of Coventry and on the border with Warwickshire. The building compromises of a 100-seater auditorium, two electrical laboratories, a boardroom, 3 teaching laboratories, eight meeting rooms and houses approximately 360 researchers and administration staff.

That is not a small building and it draws quite some electricity (my emphasis):

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Can a vehicle-to-grid extend battery-life of electric cars by ten percent?

In the previous post, I wrote about a report calculating the expected electricity price in a vehicle-to-grid system and the assumptions that went into it. One of the difficulties that was detailed in the report was the aging of the battery used in a vehicle-to-grid system. In the meanwhile, I read this 2017 article from the Dutch sustainability website wattisduurzaam.nl contradicting this. The author of the article writes that it is contra-intuitive, but that research from the University of Warwick revealed that a vehicle-to-grid system can even extend the lifetime of lithium-ion batteries…

I could somehow understand “minimize”, but a vehicle-to-grid system that extends battery life is a very strong claim.

Although the article was written in a cheering mode, it also acknowledges that battery degradation is a problem in current vehicle-to-grid systems, but that this research achieved an extended battery life. Not just a tiny extension, a whopping 10 percent extension of battery life by operating in the vehicle-to-grid system.

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More averaging: impact of electric cars on the grid

The term “vehicle-to-grid” is mentioned twice in passing in the report detailing the impact of electric cars on our grid (see previous post). I wondered whether this vehicle-to-grid was the solution to their problem. After all, their calculation was done by averaging consumption, which is not really what will happen in the real world. But when they assume some top-down system of regulating demand, then I could somehow understand their reasoning.

I didn’t find any reference mentioning “vehicle-to-grid” in the report, but I wanted to know where the CREG got these assumptions from. I found that, to my surprise, the CREG earlier wrote a report on the impact of electric cars on a vehicle-to-grid system (pdf, Dutch ahead). The report is not new, it was published in 2010 with the data from 2007 and 2008. The subject of their research is the impact of the introduction of electric cars on the electricity spot market price.

The result of the 2010 report was similar to the 2016 report. They also researched the impact of 1 million electric cars and found that only 2.5% extra electricity needs to be produced on average (compared to 4% in the 2016 report) and that base load could easily absorb that extra electricity demand. The general conclusion of the 2010 report is that charging cars during off-peak hours will lower the spot prices. This because part of the capacity of the car battery could be used to trade on the energy market, buying electricity from the grid when it is cheap (during off-peak hours) and selling it at a high price when it is expensive (during peak hours).

It gets interesting when they explain their assumptions (on page 15 – 16):

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Just 4 percent extra electricity required to accommodate 1 million electric cars?

My previous post was not completely finished when I learned that our new Flemish Minister of Energy was piggybacking on the resolved delivery problems of the Tesla 3. She wrote a post about the increase in electric car subsidy requests during the first three months of the year and framed it as a success story. It is best making hay when the sun is out.

While trying to find information on the subject of her post, I encountered a tweet in which she answered the question whether we would have enough electricity to supply for electric cars when we already now experience a substantial electricity shortage. I don’t understand the question very well (although our electricity supply is old and in disarray, we don’t have electricity shortages, yet), but her answer is intriguing (translated from Dutch):

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Sales of all-electric cars finally kicking off?

A few days ago, I came across an article titled “Substantially more electric cars sold“. My first thought when reading this headline was: “Again?!”. It was only a few months ago that I looked into an increase of electric car registrations and I was not really impressed when I found out that it was all about a 1.94% increase of something with a share of 0.22%. Now we have yet another such claim.

The article is for registered users only, but this could be seen by non-registered visitor (translated from Dutch):

The sale of electric cars is finally kicking off in Belgium. A record number of 1,085 all-electric passenger cars were registered in March. This according to figures from the automobile federation Febiac.

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Solar and wind replace nuclear?

A small interruption from my 6-years-of-blogging series. This blog documented several meaningless (or even wrong) remarks from our (now former) Flemish Minister of Energy. I was a bit sad when I heard that he chose to be mayor of Ostend in stead of Minister of Energy, but apparently he doesn’t have to be Minister to utter such remarks. On a congress organized by his party (OpenVLD) he made following claim (translated from Dutch):

Today, offshore wind turbines provide 1.2 GW of energy production.

That is not even remotely true. Belgian offshore wind provides much less than that. The 1.2 GW is the capacity. The real production will vary, but will be on average a fraction of that number.

He obviously is confusing capacity with production. Why am I not surprised? Strange however is that the error is still not corrected yet at the time I published this post (now more than a week later). Didn’t they notice it? Or do all the energy experts of that political party stand behind this number?

Then comes the interesting part that leads to the subject of this post (translated from Dutch, my emphasis):

“By 2026 we will increase this to 4GW without subsidies. From then on, the offshore wind farms will provide 20% of the total electricity requirement. This is just as much as the total electricity consumption of all Belgian families, “says Bart Tommelein.

This claim reminded me of the new energy pact made by the Flemish Green party, published a few days before the congress. It has a similar claim (translated from Dutch, my emphasis):

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Who am I to say?

When I started this blog back in 2013, I had several questions. The most prominent was how I, as an interested member of the public, could assess who is right and who is wrong. At that time, I also was looking for information on how laymen/interested members of the public could figure this out.

Initially, I played with the idea to tackle this question by using logic. I abandoned the idea rather quickly. Formal fallacies could surely distinguish between who is right or wrong, but these are not exactly the fallacies that one can readily find in the debate.

I also found some information that layman/interested members of the public had other ways of evaluating a subject, but I didn’t find much details back then. So now and then during the last six years of blogging, I contemplated on these two questions, but until recently these stayed unanswered.

Until I got this comment on a post dissecting the claim that there had been a “sudden rapid growth” of the number of registered all-electric cars in Flanders:

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