Comment by dragonwriter | Hacker News Reader

Comment by dragonwriter | Hacker News Reader

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> 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.

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.

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.

> 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.

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.

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