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by MarkusWandel 1220 days ago
Even assuming that this can be turned into practical product, 10 minute charge? With a typical EV battery on the order of 80KWh? That's 480KW charging, probably more because charge current isn't uniform over the charge cycle. Half a megawatt per charger bay.

The electrical infrastructure for mass deployment of this sort of thing will really be interesting.

2 comments

From the fist article:

> XPeng's new S4 ultra-fast charger, first announced in late 2021, is an 800 volt class EV charger with a peak power output of 480 kW (at up to 670 A and at over 700 V).

You will need definitively a new electrical installation to use that at home, and many safety measures to ensure morons are not fried.

High power DC fast chargers are not meant for residential installation.
For residential installation, you don't want fast charging. Slow charging damages the battery less, and for everyday use getting to full charge overnight is sufficient.

When you need to fast charge, you should go do it at a charger.

Which is why hydrogen cars need to be taken seriously. Not everyone is going to have access to a private charger, nor is it realistic to put up 0.5 MW chargers everywhere. There are millions of people that are better served by a car powered by fuel.
I would argue that whatever investment is needed for beefier EV charging is always going to be orders of magnitude cheaper and simpler, not to mention efficient, than the most basic network of hydrogen pump stations. This is just a gut feeling.
You'd be wrong. A hydrogen infrastructure would have the same footprint as gasoline/diesel. The stations are already there, they just need to be converted. Hydrogen distribution will mostly reuse natural gas infrastructure. On the other hand, a charging network will means a drastic expansion of power infrastructure and many new charging stations on new land.

The efficiency of electricity is also more hype than reality. If it is coming from fossil fuel power plants, it is not notably more efficient nor green. If it is from renewable energy, then you need to solve the problem of energy storage, which ironically is most easily solved via hydrogen. Nevermind the fact that you have to deal with the upfront energy needed for battery production, undermining the argument in a big way.

And of course, nothing is more efficient than not driving at all. Mass transit and walkable neighborhoods should be the main goal of green transportation. Cars are mostly a distraction and should not be emphasized. We only tolerate them because not every transportation problem can be solved in that way. They are the fallback solution.

As a fallback solution, hydrogen cars make a lot of sense, especially for those who can't justify an EV. Certainly more sensible than demanding only EVs for all cars.

Your message is not compatible with "The Clean Hydrogen Ladder" report [0] which I take as solid reference on what hydrogen investments make sense.

Here's an illustrative quote:

"By now everyone should have managed to get their head around the fundamental inefficiency of turning electricity into hydrogen, compressing it, storing it, moving it around and then converting it back into power on board a vehicle. Somewhere between half and three quarters of the input power is wasted, and this is not going to change much - there are fundamental thermodynamic constraints. Not only that, but the H2FC vehicles are also much more complicated so they have higher maintenance costs, and although hydrogen can be safely handled, you really don't want it in every garage and workshop. You can forget use cases like urban delivery, two and three wheelers, metro trains and buses."

[0] https://www.linkedin.com/pulse/clean-hydrogen-ladder-v40-mic...

That's pure gibberish. Just some marketing propaganda with zero evidence behind any of it.

In reality, batteries are not sustainable and need vast amounts of raw materials to exist. Hydrogen vehicles lets you avoid this. That is a fundamental and unbreakable advantage.

Also, a fuel cell is an electrochemical system. Meaning fuel cell cars are EVs too. The notion that somehow this is an impossible technology, or even one that has any meaningful limitations compared to any other kind of EV is entirely a lie.

If you were to convert gas stations to hydrogen stations, you'd have to change out all the tanks and fluid handling equipment.

Equipment to handle fluid at atmospheric pressure is very different from that which handles high pressure gas/fluid.

You'd have to replace the underground tanks, all of the associate plumbing, and the pumps on the surface. That's going to cost just as much as building the gas station in the first place.

That's assuming you're trucking in liquid hydrogen. If you want to put it in underground pipes, you're going to have an even worse time. You need heavily insulated pipes running at extreme pressures. Those pipes also need special coatings to prevent the hydrogen atoms from leaking out.

This is far from a simple case of "just reuse gas stations". Hydrogen presents an order of magnitude more problems than gasoline. Gasoline's main benefit is that it's pretty stable at room temperature and atmospheric pressure. It's easy to handle and store, and vanishes into the air at a much slower rate.

True, but it is not much different than gas stations selling CNG or LPG. It's doable since the land is there and you are still dealing with flammable chemicals. There is a lot of common expertise. Many hydrogen stations are in fact converted gas stations in California.