I agree there is a place for hydrogen in mobility.
I just think it's probably a very small place.

I think this piece of @Toyota chief scientist Gill Pratt is heavily skewed toward hydrogen in order to make it seem more important. Let me show you.
medium.com/toyotaresearch…
Charging speed is limited by the so called C rate of battery cells.
Simply put: larger vehicles with more cells can stomach bigger chargers.
So big trucks will charge just as fast as small cars.

And of course 90% of charging is done while parked so speed isn't an issue there.
I remember how better place imagined that we would swap batteries to overcome charging time. These days are gone and 60 minutes is simply BS. I think in 2030, new EVs coming out can charge 80% of their range within ten minutes. For something you do occasionally that's a non issue
What also bugs me is that H2 proponents compare the battery weight of an entire lithium battery with the weight of unpackaged hydrogen. But it's the hydrogen tank that dominates the weight, which is one of the reasons fuel cell vehicles are currently not (much) lighter.
Don't get me wrong: if you need to be able to travel very LONG distances without the ability to replenish energy, hydrogen has a clear advantage, esp. liquified. That's why it's great for long distance ships and planes. But required RANGE is much more important than vehicle size.
Also, the size comparison is very deceptive. Batteries can be packaged anywhere you like while lowering center of gravity. And batteries are continuing to get more compact.

Rounded H2 tanks take away more practical space than just their content.

Again a very skewed comparison.
Also, if you have to compress hydrogen you probably won't get 70% efficiency.

More importantly, fuel cells are about 60% efficient. If you also include motor losses you are at 55% or so. So the losses are much bigger.

The 90% of EVs is correct though.
So I agree we should not demonize hydrogen cars. If they give battery electric vehicles competition I'm all for it because both can be very good for the climate and there is a place for both.

But let's not skew the facts to make hydrogen seem more attractive than it is.

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More from @AukeHoekstra

15 Oct
Now that solar and wind are supercheap in some places, cheap electrolysis is the most important next step in green H2 production.

1 kW of electrolyzer produces ~200 kg of H2 per year when run at full load. If they last ten years and cost 200 euro that's 10 cents per kg of H2.
Not sure this 200 euro/kW will be reached as mentioned and that they will last 10 years but electrolysis is clearly getting pretty cheap in the future (as expected).

(10 cents/kg of H2 = 0.3 cents per kWh)
Imagine a super sunny place with cheap land produce solar at 1 cent per kWh. For 1 kg of H2 you would need around 50 kWh costing 50 cents.

If electrolysis costs only 10 cents extra that together would only be 60 cents.

There's lot's of other costs but that's just ~2 cents/kWh.
Read 8 tweets
6 Oct
Are electric cars as bad as the @FT wants us to believe?

That's something I study at the @TUeindhoven so I always read such stories with interest.

tl;dr All cars are bad but the advantage of EVs is much bigger than the @FT visual storytelling team wants you to believe.
First compliments where compliments are due: it's beautifully done.

And I think this is successful as an attempt to tell a story about the environmental problems of EVs.

Just don't mistake it for an attempt to be objective.
The storyline is "EVs seem nice but... beware!"

So they start with the positive stuff.
Read 15 tweets
7 Sep
@MLiebreich Honest question Michael: are you sure that blue hydrogen subsidies will include all fugitive emissions and exclude SMR?

I've read some intentions but nothing close to assurances. Mostly silence which leaves the door wide open for abuse.
@MLiebreich I also think we should take a system perspective, just as we do with electricity. So no designating either coal or solar to EVs and no designating cleanest or dirtiest gas to blue hydrogen but taking the average.
@MLiebreich At the moment blue hydrogen reminds me of FCEVs that are cleaner than BEVs because H2 is produced next to the windmill and BEVs get the average mix or worse, while the same H2 windmill could have powered twice the amount of BEVs.
Read 4 tweets
6 Sep
NEW argument from combustion engine fans:
move PV from Germany to Africa and make eFuels there: then we can drive just as far.

BUT PV isn't the problem.
IF it was you should still use a power line or hydrogen.
SO the combustion engine is still roadkill
🧵
frontier-economics.com/de/de/news-und…
It is true that a solar panel produces up to 5x more energy in the Sahara and that there's plenty of room there. But that doesn't negate the fact that these engines still make cities unhealthy (noise & ozone or NOx) and are expensive and maintenance prone.
On top of that these giant eFuel installations in Africa are just an expensive pipe dream of combustion engine lovers. So it's a highly theoretical debate.
And even IF we were to produce large amounts of eFuels in the Sahara, they should be used where they are most useful.
Read 9 tweets
6 Sep
I think prioritizing GDP over happiness is obvious insanity and and refusing to nudge people away from mindless overconsumption is an intellectually lazy surrender to Mammon (hypercapitalism).

But for the rest I 100% agree with Noah here.
By the way, @chrisnelder reached a similar conclusion a while back already.
And that's before we go down the rabbit hole of entropy pessimism espoused by economists who fancy themselves engineers without understanding entropy and using tortuous mathematics to avoid straightforward observations of energy abundance.
innovationorigins.com/en/tomorrow-is…
Read 6 tweets
31 Aug
Research from @TheICCT proving once again electric tractor-trailers are viable. Over 50% of road transport CO2 comes from these big rigs aka 18 wheelers and the share is growing. (More than either all airplanes or all shipping.) Electrifying these beasts is crucially important!
Have been saying this for at least five years (several master students, keynotes, and a set of blogs in 2017: elaad.nl/news/auke-hoek…) but this analysis is GOOD.

(Evertyhing from @TheICCT is thorough.)
Little point I just discussed with the author: they mention losses of 16% due to aerodynamics and 15% due to rolling resistance.

But that's for a diesel truck where the combustion engine and braking syphon away ~70%. For an electric truck engine+break losses go from 70%>~15%.
Read 9 tweets

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