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Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

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Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#31

Post by digikata »

_rpd wrote: post #26
jobu wrote: post #9

There have been two major hurdles for the development of hydrogen fuel-cell cars: 1) storing the hydrogen - hydrogen is extremely corrosive, and not very energy dense compared to gasoline 2) variable energy output - fuel cells are good at producing a steady, constant amount of power, but the power requirements of a car can be quite variable (especially for city driving) Anyone have details on how Toyota overcame thes…

For (1), the Mirai will use two 70 MPa (10,000 psi) carbon fiber tanks lined with a polyamide resin to give a range of approx. 300 miles ... http://blog.toyota.co.uk/how-does-toyotas-fuel-cell-vehicle-... http://www.plasticstoday.com/articles/toyotas-fuel-cell-car-... A Toyota exec recently fired bullets at the tanks to allay fears that they would turn fuel cell vehicles into Hindenburgs waiting to happen ... http://…

Firing bullets at it when the tank is new is just a publicity stunt. Those tanks need to be holding hydrogen for at least five years, all while being cycled from full to empty, then lets see how well they hold up.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#32

Post by derjames »

hellgas00 wrote: post #28
dragonwriter wrote: post #22

Earlier quoted context omitted.

> For fuel-cell cars to work, you would need to have energy some place that consumes water and splits it into hydrogen and oxygen, releasing the oxygen into the air, and the hydrogen into containers that can then go into some sort of infrastructure such that individual cars can be filled up with it as necessary. Yeah, sure. We know how to do this, its called electrolysis; we even know how to build fuel cells that can…

There is absolutely no way that Hydrogen would be produced via electrolysis. The process is horribly inefficient but more importantly the cheapest way to produce hydrogen is through steam reformation of coal (or organic material to a way lesser extent). You spray coal into a hot stream, methane decomposes from the mixture, then the methane is converted to Hydrogen. It's by far the cheapest way to produce hydrogen and…

And what about something like this to 'collect' hydrogen?

http://www.manchester.ac.uk/discover/news/article/?id=13372

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#33

Post by henrikschroder »

dragonwriter wrote: post #12
henrikschroder wrote: post #7

Earlier quoted context omitted.

The only game-changer I could see there would be if we could make some sort of in-your-home hydrolyzer, so that you just connect water and electricity to it, and it connects to your car to fill it up. That's on-par with the convenience of an electric car, if we ignore the safety issues of hydrogen gas leaks in urban neighbourhoods...

Regenerative fuel cells are cells with an in-cell hydrolysis system; if you could incorporate them, a fuel cell vehicle would have pretty much the same recharging UX as any other EV. Even with stationary at-home electrolysis systems, if you don't store more than one fill-up in the system, there's marginal additional risk compared to having a hydrogen-fueled vehicle in the first place.

Great, that allows you to very easily compare that vehicle to one with a chemical battery, and evaluate it on cost, range, engine power, "battery replacement", etc! And then we can avoid all this "but it runs on water" nonsense and look at the actual capabilities.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#34

Post by dragonwriter »

hellgas00 wrote: post #28
dragonwriter wrote: post #22

Earlier quoted context omitted.

> For fuel-cell cars to work, you would need to have energy some place that consumes water and splits it into hydrogen and oxygen, releasing the oxygen into the air, and the hydrogen into containers that can then go into some sort of infrastructure such that individual cars can be filled up with it as necessary. Yeah, sure. We know how to do this, its called electrolysis; we even know how to build fuel cells that can…

There is absolutely no way that Hydrogen would be produced via electrolysis. The process is horribly inefficient but more importantly the cheapest way to produce hydrogen is through steam reformation of coal (or organic material to a way lesser extent). You spray coal into a hot stream, methane decomposes from the mixture, then the methane is converted to Hydrogen. It's by far the cheapest way to produce hydrogen and…

> There is absolutely no way that Hydrogen would be produced via electrolysis.

You mean, other than the fact that it absolutely is produced that way in existing fueling stations, and much of the drive for hydrogen as part of a clean energy solution relies on the use of electrolysis (or, possibly, splitting water with nuclear reactor heat) as the generation mechanism.

> The process is horribly inefficient but more importantly the cheapest way to produce hydrogen is through steam reformation of coal (or organic material to a way lesser extent).

Its certainly a cheaper way to produce it, but its not necessarily cheaper as an overall process, because then you do need an expensive distribution infrastructure. More, the necessary distribution infrastructure, even if end-to-end efficiency including distribution costs is better, has a much higher startup cost than distributed electrolysis.

Also, distributed electrolysis buys you directly in to any improvements in efficiency, greenhouse gas reduction, etc., for large scale energy production, whereas relying on steam reformation of coal, natural gas, etc., leaves you not only maintaining more dedicated distribution infrastructure, but with a separate carbon-intensive generation infrastructure that needs its own improvements.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#35

Post by hellgas00 »

dragonwriter wrote: post #34
hellgas00 wrote: post #28

Earlier quoted context omitted.

There is absolutely no way that Hydrogen would be produced via electrolysis. The process is horribly inefficient but more importantly the cheapest way to produce hydrogen is through steam reformation of coal (or organic material to a way lesser extent). You spray coal into a hot stream, methane decomposes from the mixture, then the methane is converted to Hydrogen. It's by far the cheapest way to produce hydrogen and…

> There is absolutely no way that Hydrogen would be produced via electrolysis. You mean, other than the fact that it absolutely is produced that way in existing fueling stations, and much of the drive for hydrogen as part of a clean energy solution relies on the use of electrolysis (or, possibly, splitting water with nuclear reactor heat) as the generation mechanism. > The process is horribly inefficient but more imp…

Again how many stations exist? I'm not arguing the concept, I am arguing the feasibility. What is the cost for fueling at these stations? Solar panels generate electricity yet we don't use them to power industrial operations because solar expensive! Just like H2 from electrolysis won't be able to compete with industrial H2 production from coal. Also, what you're suggesting is using predominantly coal to generate electricity from a traditional plant (~40% eff), then transmitting the electricity to a station (90%), then creating H2(60%). Compare that to coal steam reformation (75%) and transportation (80%, being conservative), the latter is far more efficient and cheaper.

And what infrastructure do you need? A gas truck with a pressurized tank on it. The cost of hydrocarbon based h2 will displace electrolysis in large scale production.

And your last point about distributed load efficiency gains, electric cars are already able to balance load and feed into a grid. It's always going to come down to cost, I'm going to buy the cheapest h2 around and it's going to come from steam reformed coal.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#36

Post by hellgas00 »

derjames wrote: post #32
hellgas00 wrote: post #28

Earlier quoted context omitted.

There is absolutely no way that Hydrogen would be produced via electrolysis. The process is horribly inefficient but more importantly the cheapest way to produce hydrogen is through steam reformation of coal (or organic material to a way lesser extent). You spray coal into a hot stream, methane decomposes from the mixture, then the methane is converted to Hydrogen. It's by far the cheapest way to produce hydrogen and…

And what about something like this to 'collect' hydrogen? http://www.manchester.ac.uk/discover/news/article/?id=13372

When I see proof of concept I will be less skeptical. As well this only solves conversion efficiency, batteries are already +85% for conversion efficiency.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#38

Post by sliverstorm »

revelation wrote: post #19
sliverstorm wrote: post #11

Earlier quoted context omitted.

We appear to already have the infrastructure for electric cars, and at low adoption rates that's true. But according to the utilities, that infrastructure is in no way ready for sweeping adoption of electric vehicles, so then too we would need to overhaul our existing infrastructure.

We could take the gasoline, burn it to generate electricity and use that to charge electric vehicles. If you consider the massive efficiency advantage, we'd probably still come ahead over using internal combustion engines. This is in other words a complete non-issue. But I'd love to hear plans on safeguarding inevitable hydrogen leaks in residential areas. Should we tell people to get rid of their garages?

I think you are confused. Gasoline drive is perhaps 30% efficient. Electric drive is perhaps 80%. Charging batteries I don't remember, but let's call it 80%.

So what you've proposed is:

    Burn gasoline (30%) * Charge batteries (80%) * Drive e-car (80%) = 19% efficient
It works better if you have a very high efficiency gasoline-powered generator (a 60% efficient generator gets you 38% efficient) but that can't really be done at the homeowner scale.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#39

Post by revelation »

sliverstorm wrote: post #38
revelation wrote: post #19

Earlier quoted context omitted.

We could take the gasoline, burn it to generate electricity and use that to charge electric vehicles. If you consider the massive efficiency advantage, we'd probably still come ahead over using internal combustion engines. This is in other words a complete non-issue. But I'd love to hear plans on safeguarding inevitable hydrogen leaks in residential areas. Should we tell people to get rid of their garages?

I think you are confused. Gasoline drive is perhaps 30% efficient. Electric drive is perhaps 80%. Charging batteries I don't remember, but let's call it 80%. So what you've proposed is: Burn gasoline (30%) * Charge batteries (80%) * Drive e-car (80%) = 19% efficient It works better if you have a very high efficiency gasoline-powered generator (a 60% efficient generator gets you 38% efficient) but that can't really be…

I guess you are underestimating just how terrible internal combustion engines are and overestimating charging + driving losses.

Consider that hybrids or HEVs can improve substantially on the efficiency of just a pure ICE. I guess the problem with using an ICE for driving directly is that you are often forced to run it at RPMs and states where it is nowhere near that hypothetical 30% efficiency, simply to get the acceleration the user demands.

Re: Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future

#40

Post by [deleted] »

sliverstorm wrote: post #38
revelation wrote: post #19

Earlier quoted context omitted.

We could take the gasoline, burn it to generate electricity and use that to charge electric vehicles. If you consider the massive efficiency advantage, we'd probably still come ahead over using internal combustion engines. This is in other words a complete non-issue. But I'd love to hear plans on safeguarding inevitable hydrogen leaks in residential areas. Should we tell people to get rid of their garages?

I think you are confused. Gasoline drive is perhaps 30% efficient. Electric drive is perhaps 80%. Charging batteries I don't remember, but let's call it 80%. So what you've proposed is: Burn gasoline (30%) * Charge batteries (80%) * Drive e-car (80%) = 19% efficient It works better if you have a very high efficiency gasoline-powered generator (a 60% efficient generator gets you 38% efficient) but that can't really be…

[deleted]
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