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AukeHoekstra
Fraunhofer was Wrong: Hydrogen Cars are Not Cleaner than Battery Electric Vehicles and Diesel Cars are Not Close I hold them in high esteem but this study provided the misinformation that H2 Mobility paid for. It’s not he-said she-said: you can follow along.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
In a recent publication I outlined the *Top 6 Mistakes* that make electric vehicles look bad. Author André Sternberg et al. of Fraunhofer manage to make all 6 and add 1 dirty trick. I’ll frequently refer to my publication for explanation and references.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
The original Fraunhofer study can be found here: Let's start with my end-result. The arrows show what happened after I made the corrections: electric vehicles clearly emit less CO2 than hydrogen, and diesel. (Simple chart at the end later.)
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
First we remove a 'dirty trick': Sternberg assumes hydrogen will be made from wind (assumed to cause 14 gr CO2/kWh) and batteries will be charged with solar (assumed 48 gr CO2/kWh). To compare apples with apples, I use solar for both. More details below the picture.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Sternberg assumes cars and batteries are thrown away after 150k km. But we know diesel cars can last 300k and batteries even 600k. So I assume 300k. More info beneath chart, in my article and .
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Sternberg bases energy needs for battery production on an outdated 2014 scientific paper. But with scale, cell manufacturing became much more efficient. Also electricity at 805 gr CO2-eq/kWh is much too high on average (e.g. for a German factory, let alone the Gigafactory).
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Battery material use is based on Sternberg's own observation that a battery pack weights 7.5 kg/kWh (=135 Wh/kg) while a Tesla Model 3 is already at 6.25 kg/kWh (=160Wh/kg or 19% better) and it's not 2020 yet.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
But why make diy calculations based on outdated scientific literature and untraceable “own observations”? There are multiple recent sources and the bottom line: battery production causes around 65 kg CO2/kWh, not 133 kg/kWh as Fraunhofer claims.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Finally let's look at the average electricity mix that is assumed for electric vehicles and emits far too much CO2. To make the report more relevant we took EU electricity over the lifetime of the electric vehicle. The result is shown in the chart and explained in the article.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
This chart shows the end result: battery electric vehicles drivetrains are really much better for the climate than any other drivetrain we know, but hydrogen is still much better than diesel. Please retweet if someone's arguing diesel or hydrogen emit less CO2. It's not true.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Ps: the authors used numbers for the chassis that included the motor (either electric or gasoline). So this is about the *other* drivetrain components. E.g. battery, fuel cells and H2 tank.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
This is beneficial for the diesel because an electric motor+electronics is easier to manufactur than a diesel engine and all that surrounds it. (The example is even a diesel hybrid.) Could easily add 1-2 ton CO2 to the diesel (~5 gr/km).
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Pss. Just to be clear: H2 could be vital in the transition to renewables, there will be H2 niches in transport and its environmental footprint can be almost as good as electric compared to fossil fuels: this is not H2-bashing.
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AukeHoekstra 25 Jul 19
Replying to @AukeHoekstra
Psss. These 2 things can be true at the same time: 1) Biking, vehicle sharing and public transit is much better for a city and the environment than private cars. 2) Electric vehicles are much better for the environment than diesel and gasoline and sightly better than H2.
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AukeHoekstra 27 Jul 19
Replying to @FraunhoferISE
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AukeHoekstra 27 Jul 19
Replying to @AukeHoekstra
My reaction to that:
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AukeHoekstra 29 Jul 19
Replying to @FraunhoferISE
I have written a more detailed blog about it, also taking the reaction of into account.
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AukeHoekstra 30 Jul 19
Replying to @Petra195 @InnoOrigins
Mein "debunk" von FraunhoferISE's studie pro wasserstoff und diesel und gegen elektromobilität jetzt auch auf Deutsch. Danke von Studie widerlegt Studie: Wasserstoffautos sind nicht sauberer als batteriebetriebene Elektrofahrzeuge
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AukeHoekstra 2 Aug 19
Replying to @FraunhoferISE
Another German article touching upon my debunk of the pro hydrogen and diesel study.
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AukeHoekstra 2 Aug 19
Replying to @AukeHoekstra
One criticism to the article: contrary to what the article states, batteries are also ideal for 40t trucks. I did a blog series and 3 studies on that (one of which is public) and have presented on it a numerous times. E.g. here
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AukeHoekstra 2 Aug 19
Replying to @AukeHoekstra
Basically: if you use the battery more often, your payback time becomes shorter. A typical 40t truck drives 350-700 km per day (~130000km/year). So a 800 km battery would be an incredible business case and the CO2 during battery production would be recuperated in ~6 months.
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AukeHoekstra 2 Aug 19
Replying to @AukeHoekstra
A frugal e-truck uses 1.3 kWh loaded on highway and ~1.15 on average. So 800 km. range => ~1 MWh battery. At 5 kg/kWh (doable in 2020) it weights 5t. But the drivetrain can be ~3t lighter. And new EU legislation allows 40t e-trucks to weight 2t more. (Proud to have helped.)
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AukeHoekstra 2 Aug 19
Replying to @AukeHoekstra
So weight is solvable. Other problem is the battery should last at least 1 million km. With 800km range that's 1000 000/800=1250 cycles. I estimate current battery life of Tesla at ~1500 and batteries are quickly improving in this respect. So heavy electric truck are go!
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AukeHoekstra 2 Aug 19
Replying to @FraunhoferISE
has officially reacted to my criticism of its hydrogen and diesel friendly study. (They don't mention me but engage with my points 1on1 in the same order.) Let me give a quick off the cuff reaction to that.
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
1) Assuming wind (both in the medium AND the best case H2 scenario, not just the best case by the way) at 12 gr CO2 eq/kWh for H2 and solar at 48 gr/kWh is defended as: H2 will usually be made of wind (also useful as seasonal storage) and BEVs will often charge from solar.
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
I already agreed to that BUT Since H2 is expensive and useful as seasonal storage you would be nuts to put it in cars. Not all windmills will throw ~65% of energy away on the electricity=>H2=>electricity detour. Some (now even all) will feed into the grid directly.
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
So the choice becomes: do I use a windmill to charge X hydrogen vehicles or to charge 3X BEVs? Put differently: in what world is building 3x the amount of windmills to drive your cars a superior option? And yes, BEVs can also drive on solar and FCEVs can't. Is that bad?
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
So the sophistry with which H2 proponents clean their electricity to make it seem using more electricity to achieve the same result somehow reduces emissions is not something I'll ever accept. I think it's a dirty trick. But I'm curious from reactions on twitter!
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
2) Fraunhofer claims the BEV uses MORE energy than the FCEV even though a fuel cell loses 40% of the energy on its way to the electric motor where a battery loses about 5%?? We are lead to believe that the extra mass of a 60kWh battery compared to H2 is enough to achieve this.
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
I often make these calculations and I would assume a maximum of 5% more energy use, not 35%. Case in point: the larger Tesla Model X with 100kWh battery uses less energy. Fraunhofer made a big mistake here I think but hard to say which one without seeing their calculation.
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AukeHoekstra 3 Aug 19
Replying to @AukeHoekstra
What I find even more disturbing than this mistake is their singleminded and unscientific focus on the WLTP. Science should be about reality, not political+commercial deals. Everybody knows by now the WLTP is skewed by politicians and car companies. (Less than NECD but still.)
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