After many false starts, hydrogen power might now bear fruit • Hacker News Board

Re: After many false starts, hydrogen power might now bear fruit

#11

Post by Majromax » Sat, Jul 04, 2020, 1:50 PM UTC

This article looks like a fine discussion about the economics of hydrogen production, but unless I've missed something it skips over the immense storage difficulty.

Hydrogen is a difficult thing to manage in quantity. Its density is fantastically low, so storing it in gas form requires absurd pressures -- an inherent risk to any vehicle. Storing it in liquid form goes a long way towards solving the density/pressure problem, but now the system must have a full cryogenic process to keep the hydrogen liquified. (Worse yet: over time hydrogen embrittles (https://en.wikipedia.org/wiki/Hydrogen_embrittlement) metals, making storage even more complicated)

This isn't much different than the problems faced by rockets, and it's why liquid hydrogen is not considered a 'storable propellant' for long-duration flight.

In a zero-net-carbon economy, residual demand for high power density may still have to be filled by some kind of bio-derived or synthetic hydrocarbon.

Re: After many false starts, hydrogen power might now bear fruit

#12

Post by hnick » Sat, Jul 04, 2020, 1:50 PM UTC

admax88q wrote: post #2

Hydrogen production is almost entirely produced from fossil fuels currently. Its not really a low carbon energy source unless electrolysis can be made much more efficient. Its a shame this article didn't examine the production side of hydrogen.

I don't think most people consider it an energy source, more so a battery or storage medium. And cheaper storage is an important part of the renewables story because local supply can be unpredictable.

I saw this article earlier today along those lines: https://www.smh.com.au/environment/climate-change/alchemy-of...

Supposedly this stores hydrogen metal hydrides cheaper than lithium batteries, whatever that means, but I'm not qualified to judge.

Re: After many false starts, hydrogen power might now bear fruit

#13

Post by DaiPlusPlus » Sat, Jul 04, 2020, 1:53 PM UTC

kumarski wrote: post #5

Okay, going to chime in here because this is categorically wrong on so many fronts. Tldr: Impossible for civilization to make an instantaneous non-gradual switch to hydrogen fuel cells. People like Hydrogen because they're hyped about how it is: - Clean - Plentiful - Emission-less Hydrogen is difficult to handle. - Unwieldy as a gas - Boils at 20 degrees F/ - 6 degrees C / ~420 Kelvins - Tough to maintain at a high p…

What is your opinion of Toyota’s hydrogen storage system for cars? It seems to tick all the boxes.

(I just assume Toyota isn’t going big on the Mirai for the same reason Ford and GM still only pay lip-service to BEVs: they don’t want to upset their dealer network too much)

Re: After many false starts, hydrogen power might now bear fruit

#14

Post by goda90 » Sat, Jul 04, 2020, 1:56 PM UTC

admax88q wrote: post #2

Hydrogen production is almost entirely produced from fossil fuels currently. Its not really a low carbon energy source unless electrolysis can be made much more efficient. Its a shame this article didn't examine the production side of hydrogen.

The article does talk about steam reforming vs steam reforming + carbon capture vs electrolysis of water and the carbon cost and economics of each.

Re: After many false starts, hydrogen power might now bear fruit

#15

Post by threatripper » Sat, Jul 04, 2020, 1:56 PM UTC

kumarski wrote: post #5

Okay, going to chime in here because this is categorically wrong on so many fronts. Tldr: Impossible for civilization to make an instantaneous non-gradual switch to hydrogen fuel cells. People like Hydrogen because they're hyped about how it is: - Clean - Plentiful - Emission-less Hydrogen is difficult to handle. - Unwieldy as a gas - Boils at 20 degrees F/ - 6 degrees C / ~420 Kelvins - Tough to maintain at a high p…

Hydrogen might make some sense for long haul trucks. Then you need fewer refueling stations on only the major routes. You could also generate the hydrogen locally by using electricity.

Alternatively you could equip the trucks with batteries and connect them to the electrical grid via overhead lines similar to trains for recharging. Combined with autonomous driving those trucks could go non-stop and leave the highway with full batteries.

Re: After many false starts, hydrogen power might now bear fruit

#16

Post by jitendrac » Sat, Jul 04, 2020, 1:57 PM UTC

I think article missed a really large sector which uses coal and produces millions of tons of co2 each year, That is cement industry. Heating clinker to produce cement is energy intensive long process, where big investments towards technology for using Hydrogen can be fruitful.

Re: After many false starts, hydrogen power might now bear fruit

#17

Post by harg » Sat, Jul 04, 2020, 1:58 PM UTC

jakozaur wrote: post #9

Main points: 1. The only hydrogen produced from electricity is ecological. Carbon capture doesn’t work today. 2. The hydrogen from electricity is expensive, though as wind and solar get exponential cheaper, we will end up with spikes excess cheap electricity (negative prices today or disconnecting plants). It makes sense to produce hydrogen during those spikes. 3. Cars on hydrogen don’t make sense at all. The massive…

I don’t know if you had access to the whole article but it addresses all of the points you mention (except 7).

Re: After many false starts, hydrogen power might now bear fruit

#18

Post by Dumblydorr » Sat, Jul 04, 2020, 1:58 PM UTC

speedgoose wrote: post #6

I used to drive a hydrogen car once in a while a few years ago. It was nice to fill the car in a few minutes and get about 300km of range, but that was it. With the hydrogen you have so few refueling stations, they are very expensive, that range anxiety is a thing. To not improve things, reliability is very poor. My work had a hydrogen refueling station on its parking. It was often broken and actually a bit scary to…

The issue of charging was also there with BEVs, until Tesla straight up built a huge network of superchargers. The players in hydrogen say they will do the same. But for personal vehicles, hydrogen won't math out, it's greatest advantage is its energy density for trucks.

It's for long range trucks that we will see hydrogen first. Green hydrogen will act as energy storage, big renewables grids can dump excess into green hydrogen and thus avoid curtailment. Then, you replace heavy duty trucks, which need to be able to not have heavy batteries, with fuel cell trucks, and you build out 1000 large hydrogen stations across the transit network.

Re: After many false starts, hydrogen power might now bear fruit

#19

Post by maxerickson » Sat, Jul 04, 2020, 1:58 PM UTC

jakozaur wrote: post #9

Main points: 1. The only hydrogen produced from electricity is ecological. Carbon capture doesn’t work today. 2. The hydrogen from electricity is expensive, though as wind and solar get exponential cheaper, we will end up with spikes excess cheap electricity (negative prices today or disconnecting plants). It makes sense to produce hydrogen during those spikes. 3. Cars on hydrogen don’t make sense at all. The massive…

1 kg of (electrically produced) hydrogen costs more than 1000 gallons of desal.

(1 kg of hydrogen would make a few gallons of water)

Re: After many false starts, hydrogen power might now bear fruit

#20

Post by hwillis » Sat, Jul 04, 2020, 1:59 PM UTC

speedgoose wrote: post #6

I used to drive a hydrogen car once in a while a few years ago. It was nice to fill the car in a few minutes and get about 300km of range, but that was it. With the hydrogen you have so few refueling stations, they are very expensive, that range anxiety is a thing. To not improve things, reliability is very poor. My work had a hydrogen refueling station on its parking. It was often broken and actually a bit scary to…

And you always have full (trip) range every morning with an EV. Yes, filling up in 5 minutes is better than 20. Never needing to fill up is even better.