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Yeah, anything but green hydrogen is just a complicated way of keeping the status quo, fossil fuel oriented system in place. There might be a small benefit to global warming (not found in this paper), but it’s using up a finite amount of capture space.
I do think we can probably get a lot better at capturing methane leaks, though. It’s low hanging fruit.
…and even green hydrogen is much less efficient for heating and propulsion than heat pumps and battery/direct-electric. Especially in the early days when we are still working to increase the energy payback of renewables, this is not helpful! We need high efficiency usage of electricity. Making hydrogen is something you shouldn’t do unless there aren’t alternatives.
We don’t need hydrogen for heat, for transport, or for storage (possible exception being seasonal storage once you’ve surpassed 95% clean electricity… no point in hydrogen storage if you’re still only a 50% clean grid). Hydrogen trucks are more expensive (to buy and ESPECIALLY a to operate) and not necessarily any more range (possible exception if you use liquid hydrogen). We do use hydrogen industrially for all ammonia production and (believe it or not) all new iron ore reduction plants (DRI/HBI plants) in the US (they use syngas usually, a mix of hydrogen and CO, usually made from natural gas but it could be made almost entirely with hydrogen), so it’s not like we won’t find a use for the hydrogen we might produce from excess renewable power.
There's a hell of a lot of denial and negotiation when it comes to the carbon-based economy.
There is a painful amount of searching for some way to keep on digging up carbon out of the ground and turn it into something green.
So far the only real solutions are to leave the carbon in the ground and switch to wind/solar/etc.
We need to get past the denial/anger/negotiation/depression phases and just hit the acceptance phase of post-carbon energy.
Well, also that green hydrogen is a drop in replacement for blue/grey hydrogen. The hard part is building all the infrastructure. If we can build the infrastructure on blue/grey and then gradually transition to green over time, it's an easier feat than waiting until we have economical green hydrogen before starting to build.
> We don’t need hydrogen […] for transport
We’ll need it for aviation.
Hydrogen is a stupid fuel. There, I said it.
It's hard to store. It leaks away. It has poor energy density by volume (and much of the energy simply goes to compress the damn stuff) - only 3x li-ion, for your trouble. It has a crappy round-trip efficiency - only 50% for water -> electrolysis -> fuel cell. It's just a shitty battery.
The only thing it's got going for it is that it's a way of greenwashing fossil fuels.
50% round-trip efficiency and 3x the density of li-ion sounds pretty good, actually. Assuming your efficiency number is the entire cost of water -> compressed H2.
Also it's odorless, is flammable in air from 4% to 74%, and has an invisible flame during the day when it does. It's a nightmare.
Yet it's absolutely required for synthesizing hydrocarbons from CO2 so, there's that.
I mean, pick any fuel you want, their utility as stores of energy are all based on hydrogen content. So we're going to kick the fossil habit and still have fuel of _any_ sort, we're going to have to learn to produce and utilize hydrogen at scale.
Grey and blue hydrogen are transition fuels. They build a market for green hydrogen to fill. It's going to be a little messy along the way.
Last time I looked at hydrogen-electric, a huge limitation was the lifetime of the electrolyzer membrane. They are expensive and you have to replace regularly.
It's not a stupid fuel in cases where you need massive amounts of energy and can't spare the weight... Like rockets and... rockets
Hydrogen energy storage capacity underground: $1/kWh
Li-ion energy storage capacity: somewhere around $200/kWh?
So, no, hydrogen is not "hard to store". It's vastly cheaper to store it at scale than it is to use shorter-term storage technologies. The disadvantage is low round trip storage efficiency (maybe 40% if used with a combined cycle power plant) but THAT'S OK for long term storage, which will have many fewer such iterations than diurnal storage.
If you want to level grid energy use and demand over a year, batteries would be insane. Hydrogen, however, could be quite practical.
This is true, but probably could be stated better.
Increased Green Hydrogen production is an essential and inevitable part of the response to climate change.
But the people pushing it for personal transport (often putting more effort into talking down their battery equivalents than actually building and selling vehicles) and anyone suggesting blue hydrogen, as a stopgap because green hydrogen is so far away and expensive, is more pro-fossil than pro-hydrogen.
If oil and gas majors aren't annoyed by your hydrogen strategy, then you're not doing it right.
It has much better energy density than batteries, which is useful when mass is at a premium (in specific circumstances because it also requires heavy apparatus), or when you need some backup power supply to supplement a worst case scenario that would require a prohibitively large battery to handle.
Any idea about the round trip efficiency for other synthetic fuels like methane or propane? It's probably awful but may be worth the increased density over hydrogen.
One of the dirty secrets of li-ion is that in order to use it for cars, you need high voltage batteries, and if your charging source isn't similarly high voltage, your charging efficiency tanks because you spend 30-40% of your energy stepping your voltage up to a level that will charge your batteries. For example, if you charge your Tesla with a 120v AC power supply, you're looking at 58% charge efficiency, which will put your end to end efficiency at the same level: ~50%.
Green hydrogen is the only realistic alternative to nuclear in areas which rely on wind power for renewable energy. Li-ion batteries can not economically create weeks long capacity of stored energy with a charge cycle of a few times a year. Wind does not have a day cycle as solar has.
What green hydrogen need to do is become economical, and to my knowledge it is even more expensive per w/h then nuclear is.
And yet hydrogen is the only realistic solution we have for 0-emission mid/long range aircraft.
Also it can damage your ears pretty badly if it burns in open air.
I would have hoped that the hydrogen needed for fuel would be produced by the electrolysis of water using solar/wind/nuclear. Anything else is kinda silly.
I think there is hope in to hydrogen that is produced as by product of carbon capture technology, especially green cement and lithium production via sea water.
That's “green hydrogen”, and it does happen – but it's more expensive, because we already have the fossil infrastructure.
Alternatively thermochecmical production [1] with thermal energy provided by nuclear. But yes, presently over 95% of hydrogen is produced through steam reformation which consists of knocking the hydrogen out of methane and producing C02 and hydrogen (CH4 + O2 -> C02 + 2H2).
> [The GHG footprint of blue hydrogen is] more than 20% greater than burning natural gas or coal for heat and some 60% greater than burning diesel oil for heat
Totally apples to oranges comparison - heating is and always will be way more energy efficient than electricity generation on a per-watt basis because you eliminate the inefficiencies inherent in the compressors and turbines. You have to compare hydrogen to what it’s being used to replace - internal combustion engines, which are wildly inefficient.
> inefficiencies inherent in the compressors and turbines
This is not why such thermal engines/plants perform (well below) 100% efficiency. You could have isentropic (i.e., ideal, working losslessly) components and will probably still land below 50% thermal efficiency, limited simply by the Carnot efficiency. That is to say, it's a fundamental physical limit, not an anthropological limit (e.g. component quality).
I also don't understand the point you're making. If you burn these three fuels, they have certain carbon footprints. What's wrong with that comparison?
You cannot "compare hydrogen to internal combustion engines" --- that's apples and oranges, comparing a fuel to an energy conversion machine. You can compare hydrogen and fuel cells to gasoline/Diesel and ICEs, which gets closer to the whole chain (but still ignores how the fuels were procured).
Lastly, ICEs are not "wildly inefficient". Large-scale maritime Diesel engines are some of the most efficient machines we have in this sector. It's not about what's lacking to 100% --- 100% is physically unobtainable. It's about the delta to Carnot efficiency, which gets very small for these.
It's important to regard energy qualities and types, since you are comparing apples and oranges otherwise. With energy, there's no free lunch, and a number like 90% efficiency might be entirely meaningless, e.g. for electric water kettles (doesn't stop advertisers).
Thanks for pointing this out! That nuance seems to have been completely left out of the conversation
My ex wife worked at a large international airport.
They converted their entire fleet of cars, trucks,
into hydrogen.
(Yes, it is inaccurate there were still some normal fossile fuel vehicle around).
From her perspective it was great. No emissions at the airport.
No waiting to charge the truck, filling it up was comparable to putting gas in the tank.
The vehicle could run 24/7 as their old fossile fuel counterparts.
I understand that the production of hydrogen may not be good at the moment, but I hope it changes.
I would prefer to have a hydrogen car to a Li-ion battery, if and only if it became a majority platform.
Every winter, tons of people want to go up to the mountains. Given it is in the middle of winter the weather can change and roads closed.
Sometimes the wait can be several hours before the snow plows arrive and arrange slow column driving.
It is easy for the snowplows or other rescue vehicle to provide diesel and petrol and in sone version of the future hydrogen.
It is not easy to charge a lot of electrical cars. I an sure you can make trucks with huge batteries, but it will still take considerable time to charge them all, in if it is done in parallell. One truck charging 30 cars in 30 minutes or however long they will need to reach a level where they can run the heat at max and drive behind the plow.
Until they figure all this out, I feel safest with a plug-in hybrid.
Quoting Wikipedia: "As of 2020, the majority of hydrogen (∼95%) is produced from fossil fuels by steam reforming of natural gas, partial oxidation of methane, and coal gasification"
"As of 2020 most of hydrogen is produced from fossil fuels, resulting in carbon emissions."
While it doesn’t make anyone rich, a culture/lifestyle shift towards doing more with our bodies, instead of converting other energy so that we have more free time (in which to convert even more resources), might enrich us in other metrics than money.
What will it take for more people to meet their exercise needs without having to make time to exercise?
Barring one or two funerals, I’m done with air travel, and long-distance travel in general; one small step for a man, and it could be giant if we agreed on regulation that limited the amount of fuel we collectively convert.
The idea that money is wealth isn't just bad for our wellbeing, it's bad for the economy because money is meant to circulate. It's a means to an end, not the means.
True wealth only exists in the real world. That includes our bodies and the environment around us, not just our material possessions.
> The vast majority of hydrogen (96%) is generated from fossil fuels, particularly from steam methane reforming (SMR) of natural gas but also from coal gasification.
That's the problem, right there. It's hard to make those processes clean.
We need a different process for hydrogen. Or stick to 100% electric instead.
Hopefully wind/solar electric
These results look marginal, as in, if you tweak the assumptions slightly you can get a net positive. I'm not saying they're wrong, but there are quite a few results in the green economy that look like this from the outside and it's hard to tell how things will turn out before you try them.
To be clear: I think batteries are a much better choice than hydrogen for consumer applications at this point in time. It is unclear what will happen with Over the Road long haul trucking and airplanes.
You can't really compare hydrogen with gas and coal. Gas and goal are (fossil) fuels, hydrogen is a battery, or more accurately, at best an energy storage medium. Yes, you can use it for rockets, but you first have to separate it out from water using the same energy that later oxidization will return.
Right now the cheapest source of hydrogen is producing it from gas and coal. Using it as a portable storage medium for green energy is still the pot of gold at the end of the rainbow.
Any kind of carbon capture system that is intended to enable the continued burning of fossil fuels is an obviously bad idea.
We need the tech in general, so we can for example extract carbon from methane we capture from landfills and find some kind of use for it, but anyone talking about fitting it to a coal or gas power plant is attempting a greenwash.
Taxing gray gas usage for carbon and putting the money towards green hydrogen and enforcing some minimal but rising percentage of green hydrogen in the mix to bootstrap the industry is obviously better long term.
Also, that green hydrogen has many cool uses but anything that can run on mains power or batteries is probably not a good fit.
Could hydrogen electrolysis be viable as grid or building level energy storage? Round trip efficiency is bad of course, but I (naively) wonder if it wouldn't have a lot of the downsides fuel cells have for vehicles?
You could bury a huge volume of tanks beneath new buildings and store the gas at a lower pressure than we see in hydrogen car tanks - wouldn't that make the whole system simpler and more economical?
Yes, grid is a big use case. Hydrogen can be stored in salt domes for maybe $1/kWh (energy capacity cost). This is two orders of magnitude cheaper than batteries, and could be used for seasonal load leveling.
This company is claiming to replace the steam with a plasma beam and turns the carbon into a solid so no co2 emissions. The process creates hydrogen on site so just pipe natural gas no distribution problems. https://hiiroc.com/
Unless we figure out a way to reverse entropy, hydrogen is going be less efficient than any feedstock we make it out of.
If/when we achieve direct solar separation at scale hydrogen might start to make sense for transportation/portable applications at least.
Why wouldn't you just use methanol, which can be synthesized from CO2 and hydrogen, and can be used in existing internal combustion & turbine prime movers?
> Hydrogen is often viewed as an important energy carrier in a future decarbonized world.
by who? (other than japanese car makers)
Maersk and the Viking Energy project are developing the technology to use it in shipping as ammonia. The first hydrogen-fueled commercial passenger flight has already flown, and there are a number of conversions of existing aircraft happening. Airbus is also looking into it. I think for these types of applications, ammonia makes more sense, especially if you can get away with high temperature fuel cells that can use ammonia directly. For drones, hydrogen is proving to be better for aircraft needing long endurance, and is likely the future of the industry -- at least for platforms above a certain weight class.
It's quite popular with conservative politicians in Germany too.
Cummins has been investing significantly in hydrogen technologies as a replacement for diesel and natural gas power systems.
Sounds like the ethanol of hydrogen.
or we could just go nuclear
Not or, and.
The only way hydrogen even makes sense is if you build so much nuclear power that your baseline generation is peak electricity usage, and you use the extra generating capacity during low demand times to split water.
Am I correct in assuming that energy use, period, is the problem?
I would love to see how many KWH per person on the entire planet are generated every year by legit clean sources.
Solving global warming = destroying life as we know it.
Decarbonized world does not exists. It's an invention of self-righteous/do-gooders/right-thinking people. Every human activity will generate CO2, it's inevitable