this post was submitted on 01 Mar 2024
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Toyota wants hydrogen to succeed so bad it’s paying people to buy the Mirai::Toyota is offering some amazing deals for its hydrogen fuel cell-powered Mirai. That is, if customers can find the hydrogen to power it.

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[–] [email protected] 37 points 8 months ago* (last edited 8 months ago) (4 children)

Hydrogen is incredibly inefficient compared to using electricity directly. You have to first use the electricity to make the hydrogen, this is very inefficient in itself. then you have to "burn" it to drive the vehicle, which wastes most of the energy just like ICE vehicle. So you need several times the initial energy generation to drive a hydrogen vehicle the same distance compared to using electricity directly.

Of course the batteries is then the issue when it comes to EVs, so they're not a magic bullet. But I wouldn't say hydrogen is the obvious better choice either since it is so wasteful with the energy.

[–] [email protected] 11 points 8 months ago (1 children)

In a conference that in attended, they talked about usbhavimg to look at energy sources like a flow of energy and not as limited sources.

Currently, wind turbines are imtemtionally stopped, when there is so much wind that the generated electricity becomes too cheap to sell!

Instead, you could run them and use the electricity to convert the energy into hydrogen. Yes some energy is lost but it would be lost anyway as wind

With wind, sun, wave energy, we can look at energy in different ways that we usually do with fuel and coal. It's there and it just keeps coming.

[–] [email protected] 15 points 8 months ago* (last edited 8 months ago) (1 children)

Yes but the overhead we have is nothing compared to the energy needed to make everything hydrogen powered. we would need an absolute absurd amount of overhead to generate all the hydrogen from overhead alone.

It's kind of dumb to intentionally waste 75-80% of the total electric energy initially generated to power hydrogen vehicles.

Using hydrogen to store the occasional grid overhead to be used for the grid later is a great idea, it should absolutely be done ASAP...but it's not a solution to hydrogen powered vehicles.

[–] [email protected] 2 points 8 months ago (1 children)

Using hydrogen to store the occasional grid overhead to be used for the grid later is a great idea

A factory which only runs some of the time will be really expensive. From what I've seen it's way more cost effective to rely on batteries for surplus electricity.

[–] [email protected] 2 points 8 months ago

So far grid scale battery storage only scales to stabilizing the grid. It’s better than anything else at that, but it’s not cost effective to for example power a town overnight until solar is back

[–] [email protected] 4 points 8 months ago

Oh, that's a good reason, I didn't know that.

[–] [email protected] 1 points 8 months ago (3 children)

Agreed, but 2 important things in my eyes.

1 - renewable surpluses. As wind and solar keep ramping , hydrogen is a fantastic way to store that energy. Sure, there are efficiency losses but it's transportable, able to be stored long term, and able to be used from small scale to grid scale applications.

2 - total life cycle cost. There is an incredible amount of emissions embodied in evs. Haven't seen a comprehensive analysis of a h2 vehicle but I would imagine a few hundred kilos of missing lithium is a good thing.

[–] [email protected] 7 points 8 months ago

1 - renewable surpluses

Creating hydrogen is incredibly inefficient if you look at all the steps involved. It will be significantly more inefficient if you don't create hydrogen 24/7. Meaning, it'll cost significantly more to rely on a surplus of electricity. Meaning, it is way more expensive per mile or km driven.

2 - total life cycle cost.

The tank in an hydrogen car is only good for 8 to 10 years. You're replacing one bit that might fail with loads of other bits that might fail.

I think people aren't understanding how inefficient hydrogen is. Especially with the suggestion that hydrogen somehow is better than EVs, despite hydrogen cars often still having all the EV tech in a car.

[–] [email protected] 5 points 8 months ago (1 children)

But the hydrogen also has to be transported, which produces CO2, you need containers for that that also produce CO2 when getting manufactured. I'm not saying it's more than with a battery but it could be. We'd need actual numbers to really know tho.

[–] [email protected] 1 points 8 months ago

I've seen plans for hydrogen fuel stations to create the hydrogen there on site.

[–] [email protected] 2 points 8 months ago

1 - renewable surpluses. As wind and solar keep ramping , hydrogen is a fantastic way to store that energy. Sure, there are efficiency losses but it's transportable, able to be stored long term, and able to be used from small scale to grid scale applications

Grid storage is a genuine problem that needs solving, but there's no particular reason to believe hydrogen is going to be the technology to fill that niche. There are much simpler and more efficient competitors, not least of which being pumped hydroelectricity, but also including exotic technologies like molten salt thermal plants or compressed air mineshafts. And batteries, for that matter; once portability stops being a concern, other battery chemistries start to be an option which don't include lithium at all, like sodium-sulfur.

And even if hydrogen electrolysis does make sense as a grid storage medium, there's no particular reason to think it's a good idea to package up this hydrogen, transport it, and stick it in vehicles to convert into electricity through their own mini power plants. The alternative, where hydrogen is simply stored and converted back into grid electricity on site to meet demand leveling requirements seems far more likely.

[–] [email protected] 1 points 8 months ago (1 children)
[–] [email protected] 1 points 8 months ago* (last edited 8 months ago)

Which is why i put it in quotation marks. I couldn't remember the name of the reaction, so that was my go-to replacement.