Toyota Embraces Fuel-Cell Cars for Post-Gasoline Future • Hacker News Board

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

#21

Post by mikeash » Fri, Dec 19, 2014, 10:15 PM UTC

MrGuyUser wrote: post #3

Hydrogen is the most abundant element in the universe, but it's very rare on earth so it has to be manufactured. So the oil companies totally would love you to switch from the oil they will sooner or later not be able to fracking get anymore to hydrogen which they can raise prices on until the day when nuclear fusion becomes something they could sell again as long as it remains expensive enough to be sellable. Hydrog…

Just a nitpick: hydrogen is extremely common on Earth, but it's uncommon to find it by itself, rather than bound into some larger molecule like water or hydrocarbons.

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

#22

Post by dragonwriter » Fri, Dec 19, 2014, 10:15 PM UTC

henrikschroder wrote: post #6

Good that there's serious money being sunk into alternatives to electric cars, more is always good. But I'm seriously tired of the fact that all articles about fuel-cells enthusiastically exclaims that "it's only byproduct is water!!!!", as if hydrogen was some sort of magic alternative to hydrocarbons. It's not, it's an energy transmission medium, not an energy source. For fuel-cell cars to work, you would need to h…

> 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 both generate energy and act as electrolysis systems.

> And if you think about the amount of gasoline infrastructure that exists, we'd have to pretty much duplicate that, or convert that, into hydrogen shipping infrastructure, which is a pretty tall order.

No, we don't. Because -- as many currently existing hydrogen stations, like the public one in Emeryville, do -- you can very easily do the electrolysis at the filling station. So you just need water distribution infrastructure (which is one of the basic necessities of civilization) and electricity distribution infrastructure (which, as you note, is likewise a solved problem), and then you don't need any additional hydrogen distribution infrastructure.

> So the story for electric car adoption is "You don't have to take trips to the gas station anymore!", but the story for fuel cell car adoption is "You have to take trips to a new type of gas stations that don't exist yet!".

Well, except that they do exist now.

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

#23

Post by r00fus » Fri, Dec 19, 2014, 10:18 PM UTC

secabeen wrote: post #15

MrGuyUser wrote: post #3

Hydrogen is the most abundant element in the universe, but it's very rare on earth so it has to be manufactured. So the oil companies totally would love you to switch from the oil they will sooner or later not be able to fracking get anymore to hydrogen which they can raise prices on until the day when nuclear fusion becomes something they could sell again as long as it remains expensive enough to be sellable. Hydrog…

They don't mention the price because current systems cannot accurately measure the amount of H2 being dispensed into the car. Every Fuel Cell car comes with free fuel coordinated by the manufacturer.

But you can measure the cells or the energy used to fuel the car each time, no?

The fact that the manufacturers are subsidizing it makes me very suspicious of why they're providing it.

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

#24

Post by mikeash » Fri, Dec 19, 2014, 10:19 PM UTC

teraflop wrote: post #8

MrGuyUser wrote: post #3

Hydrogen is the most abundant element in the universe, but it's very rare on earth so it has to be manufactured. So the oil companies totally would love you to switch from the oil they will sooner or later not be able to fracking get anymore to hydrogen which they can raise prices on until the day when nuclear fusion becomes something they could sell again as long as it remains expensive enough to be sellable. Hydrog…

The article does mention price: "While EVs take hours to recharge, the fueling cost is a fraction of the roughly $45 a hydrogen fill-up will cost." That's more expensive than gasoline, but as of a few months ago the price difference would have only been about 30% compared to my relatively fuel-efficient Honda Fit. The gap is larger now thanks to the recently plummeting gas prices in the US, of course. > And also Hydr…

Keep in mind that the $45 fill-up cost is for about 300 miles of driving, versus 4-500 miles for a typical gasoline car.

At current prices, my Prius v will go about 500 miles on a $30 fill-up, which would cost $75 for hydrogen, assuming $45 gives you 300 miles. Even if gas goes back to $4/gallon, it's still $45 for ~500 miles.

A full charge on a Model S would cost me something like $8, by comparison. Less if I went for time-of-use metering and charged it at night.

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

#25

Post by seanflyon » Fri, Dec 19, 2014, 10:20 PM UTC

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…

H2 is difficult to store. To store enough of it to be useful it needs to be either very high pressure or so cold is becomes a liquid. Because it is so small, it tends to leak through most materials and can cause them to become brittle (http://en.wikipedia.org/wiki/Hydrogen_embrittlement) but it is not "extremely corrosive". Thick carbon fiber tanks can store H2 at high pleasure so that with the efficiency of an electric drive-train, the car has good range.

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

#26

Post by _rpd » Fri, Dec 19, 2014, 10:21 PM UTC

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://www.autoblog.com/2014/01/16/toyota-fires-bullets-hydr...

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

#27

Post by dragonwriter » Fri, Dec 19, 2014, 10:22 PM UTC

mrfusion wrote: post #17

So why can't we just run fuel cells in reverse to refill the h2? That way you could just treat it like a more efficient battery.

You can design fuel cells that will let you do this, but they are, IIRC, both more expensive and bulkier, so not ideal for most vehicle applications.

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

#28

Post by hellgas00 » Fri, Dec 19, 2014, 10:40 PM UTC

dragonwriter wrote: post #22

henrikschroder wrote: post #6

Good that there's serious money being sunk into alternatives to electric cars, more is always good. But I'm seriously tired of the fact that all articles about fuel-cells enthusiastically exclaims that "it's only byproduct is water!!!!", as if hydrogen was some sort of magic alternative to hydrocarbons. It's not, it's an energy transmission medium, not an energy source. For fuel-cell cars to work, you would need to h…

> 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 would easily cost a fraction of hydrogen produced from electrolysis. This process is also extremely CO2 intense.

I really have to wonder if this is just a show put on by Toyota. The viability of H2 production is dubious at best, and at worst if you consider our drive towards a low carbon economy.

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

#29

Post by IndianAstronaut » Fri, Dec 19, 2014, 10:48 PM UTC

henrikschroder wrote: post #6

Good that there's serious money being sunk into alternatives to electric cars, more is always good. But I'm seriously tired of the fact that all articles about fuel-cells enthusiastically exclaims that "it's only byproduct is water!!!!", as if hydrogen was some sort of magic alternative to hydrocarbons. It's not, it's an energy transmission medium, not an energy source. For fuel-cell cars to work, you would need to h…

>And if you think about the amount of gasoline infrastructure that exists, we'd have to pretty much duplicate that, or convert that, into hydrogen shipping infrastructure, which is a pretty tall order.

Imho, the only way to do this would be to have solar assisted charging stations in parking lots across the country.

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

#30

Post by hellgas00 » Fri, Dec 19, 2014, 10:56 PM UTC

masklinn wrote: post #10

henrikschroder wrote: post #6

Good that there's serious money being sunk into alternatives to electric cars, more is always good. But I'm seriously tired of the fact that all articles about fuel-cells enthusiastically exclaims that "it's only byproduct is water!!!!", as if hydrogen was some sort of magic alternative to hydrocarbons. It's not, it's an energy transmission medium, not an energy source. For fuel-cell cars to work, you would need to h…

> And if you think about the amount of gasoline infrastructure that exists, we'd have to pretty much duplicate that, or convert that, into hydrogen shipping infrastructure, which is a pretty tall order. On the other hand, electrolysis can be significantly more distributed than gasoline, you don't need a limited number of refineries anymore. Hydrogen can be generated city-wise, at the station, or even (with further ef…

You need to pressurize the hydrogen to 5-10 kpsi which requires a compressor in every home, this cuts efficiency. Electrolysis is also very inefficient (%65 is usually cities as the upper efficiency[1]). Most importantly the cheapest way to produce hydrogen is through stream reformation of Carbon based fuel (high CO2 emissions req), making electrolysis cost prohibitive.

Hydrogen is not a great way to go, especially when you consider that batteries and electric motors are already very efficient. Working on energy density in batteries would be more cost effective then chasing after H2.

[1]http://gcep.stanford.edu/pdfs/hydrogen_workshop/MacQueen.pdf