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A viable pathway for hydrogen as fuel

vox.com

11–20 of 51 posts

Re: A viable pathway for hydrogen as fuel

#11
post #10

Earlier quoted context omitted.

Hopefully solar cells will become cheap enough quickly enough. It would be awesome to have a small hydrogen plant at home.

What would you use the hydrogen plant for? For the same amount of solar energy, a Tesla is going about 3x further than a Mirai, and a heat pump would provide much more heat your house.

Mirai is one of the first production HFC vehicles, well below what's feasible. Total solar energy is not really a constraint, refueling time and amount of stored energy are.

Re: A viable pathway for hydrogen as fuel

#12
post #10

Earlier quoted context omitted.

What would you use the hydrogen plant for? For the same amount of solar energy, a Tesla is going about 3x further than a Mirai, and a heat pump would provide much more heat your house.

Mirai is one of the first production HFC vehicles, well below what's feasible. Total solar energy is not really a constraint, refueling time and amount of stored energy are.

Total solar energy is a constraint, as someone has to pay for the cells and to have space to set them up. If you want to power your own car, don't you think it makes a difference whether you need 1x or 3x the area covered with solar cells?

Re: A viable pathway for hydrogen as fuel

#13
post #10

Earlier quoted context omitted.

Hopefully solar cells will become cheap enough quickly enough. It would be awesome to have a small hydrogen plant at home.

What would you use the hydrogen plant for? For the same amount of solar energy, a Tesla is going about 3x further than a Mirai, and a heat pump would provide much more heat your house.

For energy storage for the night.

Open fuel cells storage can be much cheaper than battery based storage. You can store energy for a long period, paying by the maximum power, not storage capacity.

That said, molten salt cells look way more promising than hydrogen.

Re: A viable pathway for hydrogen as fuel

#14
post #5

Earlier quoted context omitted.

And due to the inefficiency of the components, it is a very bad battery. That is the main problem, as attractive it would be to produce hydrogen via solar.

But wait, a "tall, rangy, blond, inveterate maker and builder whose eyes light up when he talks engineering" claims he's solved all efficiency and and storage problems with super-secret technology. Incidentally, he's also the CEO of the company and probably paying for the piece: >To date, most hydride fluids have been less energy dense than compressed hydrogen, and far short of fossil fuels. They weigh too much for t…

I'm curious about his early career in video compression. I'm thinking of a friend whose first job was working with a video compression startup whose secret algorithm was to hide ethernet cables inside the power cord.

Re: A viable pathway for hydrogen as fuel

#15
post #5

Earlier quoted context omitted.

And due to the inefficiency of the components, it is a very bad battery. That is the main problem, as attractive it would be to produce hydrogen via solar.

But wait, a "tall, rangy, blond, inveterate maker and builder whose eyes light up when he talks engineering" claims he's solved all efficiency and and storage problems with super-secret technology. Incidentally, he's also the CEO of the company and probably paying for the piece: >To date, most hydride fluids have been less energy dense than compressed hydrogen, and far short of fossil fuels. They weigh too much for t…

I think we should be skeptical. That said there are some points in the article that indicate there may something more than fluff. Let the early adopters try some retrofits themselves and we shall see whether the results are there related to battery performance.

Re: A viable pathway for hydrogen as fuel

#16

Hydrogen does have a lot of problems which other commenters here point out. But if HyTech is to be believed, some of these problems are solved. Probably their most significant claim, is hydride storage at ordinary temperature / pressure with safe, practical, cost effectiveness in recovering that stored energy.

HyTech doesn't solve the main problem with hydrogen - that there isn't any available as fuel, and it takes more energy to extract the hydrogen than you get back from burning it or even using it in a fuel cell.

The idea of injecting small amounts of hydrogen into a combustion engine to improve fuel economy is not new, but congrats if they can bring that concept to market. That would be a win, but is not the same as hydrogen as a primary fuel.

Re: A viable pathway for hydrogen as fuel

#17
post #3

The article names it, but then does not dive deeper into it: the hydrogen chain has huge energy losses. First, electrolysis unfortunately has not a high efficiency - I have read numbers around 70%, but then the compression of the produced hydrogen takes a lot of energy, as compressing gases heats them up. Then the hydrogen has to be transported and stored, requiring further energy. Finally, you have to use the hydrog…

How does that compare to using batteries? Batteries are re-usable of course, but also degrade over time and need to be replaced.

Re: A viable pathway for hydrogen as fuel

#18
I think using it as a safe battery is a neat idea. I understand there are significant losses as compared to li-ion batteries, but the fact that the system has a longer lifespan is really interesting.

It's a way to preserve energy during surplus. As a gardener I'm constantly balancing inputs and outputs. A huge tomato harvest eaten raw off the vine is the most efficient use.

But during a huge glut, I cannot eat the tomatoes fast enough so I start freezing tomatoes and produce sauce.

I trade energy, and human time and labor to extend the shelf life of the tomato.

In this sense, from my naive perspective, A hydride fluid battery if cheap enough to build/install would be a great way to store surplus energy from solar / wind / etc.

Re: A viable pathway for hydrogen as fuel

#19
Most counterarguments related to Hydrogen refer to the poor efficiency of converting (electric) energy to Hydrogen and back.

True, directly using that electric energy from wind or solar is definitely the best option.

However, that is not always possible, since there is no place to consume, transport or store that electric energy.

Furthermore, scrapping all ICE vehicles for BEVs is most likely the end goal. But replacing the worldwide fleet of vehicles will take decades.

HyTech seems to be on to something for these two scenarios.

If for instance you can capture some of the excess solar and wind energy in a metal hydride for some hours, weeks, or even months, you will on a larger scale reduce the load of the electric grid.

And if some of that Hydrogen can be burnt instead of Diesel, the car or truck in your driveway is both cleaner and less dependant on fossil fuels.

Re: A viable pathway for hydrogen as fuel

#20
post #18

I think using it as a safe battery is a neat idea. I understand there are significant losses as compared to li-ion batteries, but the fact that the system has a longer lifespan is really interesting. It's a way to preserve energy during surplus. As a gardener I'm constantly balancing inputs and outputs. A huge tomato harvest eaten raw off the vine is the most efficient use. But during a huge glut, I cannot eat the to…

Love the tomato analogy - exactly why you need to convert energy, even with the efficiency loss.
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