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I fail to see an economic future for hydrogen as a fuel source. If it is produced from e.g. methane (the blue version), then we are burning more methane than we

• Robotbeat 5y ago
  Yup. The exception is industrial processes that use hydrogen chemically, like ammonia production and steel production.
• verelo 5y ago
  So i kind of agree but wonder if it is usable as a means of storage of energy. Electricity is easy to generate but hard to store, we have done a great job of figuring out how to safely store gases. Could we not generate electricity in areas where it’s not needed and simply ship in the hydrogen? I feel like it’s a useful tool in the journey of replaying a fossil fuel economy.
  • bayindirh 5y ago
    Isn't hydrogen is one of the hardest gases to store, and seeps out of almost everything due to being the tiniest atom/molecule of all?
    • kuschku 5y ago
      You can turn hydrogen into methane in an exothermic way, which you can store very easily.
      • beervirus 5y ago
        That completely defeats the purpose of using hydrogen instead of methane.
        • amanaplanacanal 5y ago
          As long as it isn't adding fossil carbon, it seems fine to me.
          • beervirus 5y ago
            Where would the carbon come from that turns hydrogen into methane? It’s not being sucked out of the air.
            • masklinn 5y ago
              > It’s not being sucked out of the air. It could be if it comes from wood or charcoal (though that seems unlikely).
          • Lio 5y ago
            Methane is reputedly much worse for global warming than CO2 though. I’ve heard 4x worse before. If that’s true then inevitable leaks of unburnt methane would not be a good thing at all.
            • leoedin 5y ago
              It is, but only for a short time - I think 9 years or so. It's broken down in the atmosphere into CO2 and water.
              • mech422 5y ago
                So its worse the C02 for 9 years... And then _becomes_ CO2 ? Not seeing how this is a win?
                • leoedin 5y ago
      • hannob 5y ago
        Which is very energy intensive, as you need to capture CO2 for this to work. And it adds the problem of methane leakages (methane itself is a powerful greenhouse gas). The most promising chemical to use as a hydrogen carrier is ammonia. It has its problems, too, but it doesn't contain carbon, which is a huge bonus.
    • verelo 5y ago
      Yeah i have read this before. I was thinking a big opportunity of coastal communities would be hydrogen from electrolysis but that lead to the reading about molocule size…nothing is easy.
  • adrianN 5y ago
    https://en.wikipedia.org/wiki/Power-to-gas https://en.wikipedia.org/wiki/Power-to-gas is a fairly popular proposal for seasonal storage. You probably want to turn the hydrogen to Methane to make it easier to store.
• roboticmind 5y ago
  I think for cars that's probably the case, but that might be too focused on cars. A possible future for it might be for large planes, boats, etc. that would really need the higher energy density of hydrogen vs batteries. The inefficiency is of course not going to be great, but it means those could possibly use renewable sources (depending on hydrogen production). Or maybe some major battery advancements come before that and make energy density less of an issue ¯\_(ツ)_/¯
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  • m4rtink 5y ago
    Actually the energy density of hydrogen due to its low density and special storage requirements. IMHO synthetic methane or synthetic liquid fuel based od captured CO2 is a better option.
    • _fizz_buzz_ 5y ago
      Don't you make these from hydrogen?
      • MisterTea 5y ago
        Yes. https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_process https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_proces...
      • marcosdumay 5y ago
        They are not "hydrogen as a fuel". There a plenty of uses of hydrogen, and they won't stop with electrification. But we probably won't be using them as fuel any time soon (except where its energy density is important enough to override price, flexibility and some safety concerns).
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• tjs8rj 5y ago
  Exactly, that’s why all society is run on photosynthesis ;)
  • HPsquared 5y ago
    Well, fusion power really.
• timthorn 5y ago
  It can also be produced from waste streams - eg contaminated plastic that can't be recycled. The process is self powering so the H2 production cycle is highly efficient as well as reducing waste to landfill. https://www.powerhouseenergy.co.uk/technology/ https://www.powerhouseenergy.co.uk/technology/
• rswail 5y ago
  It's a way of shipping solar power. There are plans for green hydrogen in the North West Australia area, using solar power to generate hydrogen that is shipped to Japan and other Asian destinations.
• roenxi 5y ago
  What then would be the plan for a 7+ day disruption to the power grid? At the moment, the backup plan is generally diesel generators, and the transport grid is independent of the electrical. Going full battery changes the risk profile quite substantially.
• dan-robertson 5y ago
  Currently it seems that batteries are an expensive technology. And we have limited capacity for their production. So having plug-in hybrid EVs (which can run on batteries for most everyday journeys) or cars running on (green) hydrogen means that sufficiently more greener vehicles can be produced such that more emissions can be avoided sooner than if the focus was battery EVs. Furthermore, BEVs are heavier and cause more road wear (some wear scales with the fourth power of the weight over an axle)
• MrsPeaches 5y ago
  As others have pointed out it might be used for flight/boats. In general though saying it isn’t useful for cars is kind of missing the point of new sources of energy. New sources of energy (and the associated prime movers) allow new forms of transportation. For example you couldn’t really make a car using steam power. That was only possible with gasoline and an IC engine. Looking at it another way: what new forms of transportation would be possible with hydrogen? Personal flight maybe? We do a lot of really inefficient things if there is a market for it.
  • KozmoNau7 5y ago
    > For example you couldn’t really make a car using steam power. That was only possible with gasoline and an IC engine. Stanley (and others) made steam cars in the early 20th century. By all accounts they were quite nice, but did have drawbacks in regards to needing pre-heating, and they were rather expensive luxury cars. Steam cars were absolutely a thing, though. Electric cars too, but the battery technology of the time was too primitive for long range. Also, hydrogen isn't a source of energy, it is merely a storage medium. https://en.m.wikipedia.org/wiki/Stanley_Motor_Carriage_Company https://en.m.wikipedia.org/wiki/Stanley_Motor_Carriage_Compa...
    • loicd 5y ago
      There was also Nicolas-Joseph Cugnot who built a steam "car" in 1770. https://en.wikipedia.org/wiki/Nicolas-Joseph_Cugnot https://en.wikipedia.org/wiki/Nicolas-Joseph_Cugnot
    • jeltz 5y ago
      > Also, hydrogen isn't a source of energy, it is merely a storage medium. Yeah, we used to power cars with wood during WW2 but wood was just the storage medium. The wood was used to create carbon monoxide which was used in an internal combustion engine.
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• api 5y ago
  Is there a way to turn CH4 into C + 2H2 and bury the C or use it for some industrial use that does not result in it being burned or emitted into the atmosphere? (Plastics? Some kind of building material additive? Roads?) If so it would be a way of getting some percentage of the energy from CH4 without releasing CO2 into the atmosphere. I can't see hydrogen for cars and stuff due to lack of infrastructure, but if we got better and cheaper H2 fuel cells I could see a natural gas power plant that emits absolutely zero CO2. The loss of energy by converting to H2 and throwing away C would at least partly be compensated for by the high efficiency of fuel cells vs. heat engines.
  • iamthemonster 5y ago
    Yes, methane pyrolysis. You can search for "CSIRO Hazer Process" for an example. As I understand it, you bubble methane through a very high temperature liquid metal, and it pyrolysis the methane into hydrogen and graphite. I am not sure of the economics or the conversion rate of methane.
• madsbuch 5y ago
  The lost energy in transforming to hydrogen might be merited by not using scarce and environmentally problematic materials in batteries.
• jillesvangurp 5y ago
  It would require a clean energy surplus and prices of clean energy to drop enough that the generated green hydrogen is cheaper than blue and grey hydrogen. Both are going to happen eventually. If you look at price trends, you can pretty much calculate when that might happen. A few decades from now, blue hydrogen will be more expensive than green hydrogen. The grey variety is likely to be heavily taxed with carbon taxes by then as well but even without that it will eventually end up being more expensive than green hydrogen. Grey hydrogen is only cheap if we let you dump 7kg of CO2 in the atmosphere for every kg of hydrogen for free. Capturing and storing that 7kg of CO2 is not going to be cheap either. 1kg of hydrogen is about 33 KWH of electricity with a decent fuel cell. It takes at least 3x the kwh of clean electricity to create that. So, about 100kwh. The price of grey hydrogen is about 0.70$ per kg. That's the dirties and cheapest variety. A more common price is > 2$/kg (still grey) in most parts of the world. Blue hydrogen costs more like 5$ per kg. So it's about 2-5x the cost of grey hydrogen. So, get price competitive with grey hydrogen, green hydrogen would have to be generated using clean energy costing less than 0.7 cents per kwh. Once we hit that price point, it will be the cheapest form of hydrogen. Current grid prices are way higher than that but a few recent bids for solar and wind plants came out at around 1.2 cents per kwh. So we're not that far off from hitting that price point.
  • state_less 5y ago
    Your projections seem pretty good. Renewable energy is likely to continue to get cheaper, opening up power to gas possibilities (e.g. green hydrogen). Something I think is missing in these hydrogen discussions on energy storage is LiFePO4 cells. They give very good round trip efficiency, are simple to operate and have been plummeting in price. https://about.bnef.com/blog/battery-pack-prices-cited-below-100-kwh-for-the-first-time-in-2020-while-market-average-sits-at-137-kwh/ https://about.bnef.com/blog/battery-pack-prices-cited-below-... If prices continue to decline at the current trend, I’d expect to see large scale batteries used to store energy for use over multiple days. For small towns, this could be a relatively maintenance free and economical option to only draw from the grid on the days of the week when you have surplus wind or solar.
  • coderenegade 5y ago
    Green hydrogen is being produced today at around $2.30/kg at Ningxia in China. The actual price they quote is $0.20 per cubic meter, [here](https://www.upstreamonline.com/energy-transition/chinese-company-starts-commissioning-worlds-largest-solar-powered-hydrogen-project/2-1-999379 https://www.upstreamonline.com/energy-transition/chinese-com...), which if you work backwards from a density of 0.089kg/m^3 at SSL conditions give roughly $2.24 per kg. That's a 200MW facility; a much larger 2.1 GW facility has just started construction in Inner Mongolia and is expected to come online in 2023. It's possible this facility reaches price parity with grey H2 just based on economies of scale. Also, 33kWh is the upper bound for the energy you get out of hydrogen. Practically, a fuel cell will get 60-70% of that, depending on the type. Electrolysis is around 90% efficient today, depending on the type of electrolyzer, and how you measure. SOECs can get better than 100% apparent efficiency by utilizing waste heat. Most sources I've seen for green H2 put the threshold for economic viability at around 2c per kWh. At that price you're still more expensive than grey, but you're at least within spitting distance, and this seems to line up with the Chinese figures.
• sandworm101 5y ago
  It is competative as a medium for energy storage and in some cases for transportation. The line losses on a hydrogen pipeline are tiny compared to those of electrical transmission lines. A two-inch pipe full of compressed hydrogen can deliver massively more energy than a conductor at the same price per mile. Hydrogen as a direct swap for natural gas is an attractive concept in areas like mine that suffer very low renewable energies seasonally. (Northern winter. Little sun/wind for several months.)
  • ashtonkem 5y ago
    Line losses are low, but compression losses are very high.
    • coderenegade 5y ago
      Not necessarily. High pressure electrolysis tends to be very efficient, and gets you over the hump of getting to 200 bar with only around 3% energy loss. Compression energy is logarithmic, so getting to 700 bar from that point takes less than half the energy that we would have spent getting it 200 bar. Figures I've seen have it at around 6-8% energy lost to get to 600-700 bar (the last part is done on gas, which is less efficient). That said, if we really wanted to, we could do deepwater electrolysis and let the Earth do the compression for us. You wouldn't even need oceanic electricity generation, because there's enough of a pressure differential between the surface and, say, 2km depth, that you could comfortably siphon some of the pressure in a turbine to power the reaction. The limitations at this point are mostly engineering and manufacturing -- we know how to do electrolysis at those pressures, and we can even do salt water electrolysis.
      • throwawaylinux 5y ago
        How could you comfortably siphon some of the pressure in a turbine to power the reaction? What does that mean?
        • coderenegade 5y ago
• ashtonkem 5y ago
  It might have some utility in places where energy density matters, such as ocean going transport.
• a3n 5y ago
  Green hydrogen is a way to store more electricity (effectively) in a car than can be stored in a battery. More range, and less weight.
• belorn 5y ago
  The reason why the Swedish and German green party is so much in favor of green hydrogen is that it seems to be the best bet in their view for a future where the primary source of energy is wind. A storage for wind need to be able to last for months, have a output capacity that is proportional to the capacity of the wind, and be expected to repay the storage investment within a reasonable time frame. The other storage alternatives each have their major drawbacks. Lithium batteries work great for solar as there you only need a few hours of capacity, and the current economical setup seems to be about 80% of output for 4 hours. Each day they get charged and each night they discharge and provide a relative fast return of investment. This doesn't work for wind. Massive amount of reverse hydro has also been suggested, but getting the capacity up to the same output as current wind installations are difficult. Having a country like Germany operating for months on only hydro power would require a lot of land and constructions, both which carries with them a lot of initial pollution in terms of both methane and co2. It is also very expensive. There are a few other lesser know storage suggestions like rust batteries and heat storage, but I have yet to hear any of them being currently economical viable to run a whole country. Green hydrogen can however be created through converting a wind farm into a hydrogen production farm. The cost is currently still prohibitively more expensive compared to nuclear, but it is still the place where those political parties I mentioned early is putting their bets. They are hoping that prices will go down enough that they can start building those kind of wind farms and then convert existing fossil fuel burning power plants and infrastructure to use hydrogen instead. (I had switched green to blue. Whops. Fixed).
  • leoedin 5y ago
    Do you mean green hydrogen? Blue hydrogen is made from methane - it is essentially a fossil fuel.
    • belorn 5y ago
      Yes. Those political parties are betting on green hydrogen. I was commenting on why they are looking towards using hydrogen and wind farms that generate hydrogen, but wrote the wrong color.
  • hannob 5y ago
• hannob 5y ago
  The biggest misconception about hydrogen is that it has something to do with cars. The whole "but BEV!" discussion is a distraction that has nothing to do with the real use cases of hydrogen. Hydrogen will be extremely important in a decarbonized economy, e.g. as a chemical feedstock or as a reduction agent for steel. Likely it will also form the basis of some fuels for ships (maybe ammonia) or planes.
  • hollerith 5y ago
    If ammonia-powered ships are visiting a port, then that port and any nearby cities need an evacuation plan in case of an ammonia leak.
    • hannob 5y ago
      Ammonia has potential safety issues, but you should be aware that there are already ammonia ports and ammonia ships. Not using it as a fuel, but transporting it. So while ammonia needs to be handled safely if it's being used as a fuel, there already is a big ammonia industry today that has plenty of experience in handling it.
  • specialist 5y ago
    Correct. The threshold is renewable energy used to produce methane and ammonia, more economically than fossil fuels sources. Then H2 economy becomes inevitable. For transportation, tackling all the use cases Li-ion doesn't. In other words, FCEV compliments BEV. If we unlock H2 soon, maybe civilization can survive climate crisis.
  • Gibbon1 5y ago
    > reduction agent for steel Direct electrwinning is about 85-90% efficient. Why add an extra step by using hydrogen? Not to mention eletrowinning iron is a wet process. Where with reduction with hydrogen is a hot process. I think 'hydrogen' is basically just an attempt to preserve the legacy power relations that have grown up around coal/oil/natural gas. If people can be convinced it's viable they can kick the can down the road for another 10-20 years.
• atonalfreerider 5y ago
  Every discussion of green hydrogen should include a mention of solar thermal zinc hydrolysis. Sunlight is used to heat water and zinc to a relatively low temperature point where hydrogen is released: https://udspace.udel.edu/handle/19716/21765 https://udspace.udel.edu/handle/19716/21765
• credit_guy 5y ago
  I'm not entirely convinced about the rationale for hydrogen, but I'll play devil's advocate. If you burn the CH4 at the place of extraction, then you need a way to transport the electricity. This is a hard problem. You can instead ship the natural gas via pipes (or LNG) to some other place, close to the consumer, where it will be burned in a power plant. For this option, there will be leaks proportional to the distance the gas is shipped. A pipeline 100km long will leak 10 times more than a pipeline 10km long. When the famed analysis that claimed 3.5% average CH4 leakage came out, they simply did not consider the length of the pipe. If you instead immediately convert the CH4 into H2, and ship that via pipes, then you have no reason to have CH4 leaks beyond a tiny amount associated with the extraction itself (which would be there even if you decide to convert the gas into electricity on the spot). So, all in all, there's a case to be made that the conversion of CH4 into H2 would result in great reductions in overall greenhouse gas emissions.
  • HALtheWise 5y ago
    I don't understand why the leak rate from H2 pipes wouldn't be as bad as CH4. In fact, shipping hydrogen is generally much harder, since it requires such deeply cryogenic temperatures to stay liquid, unlike liquid natural gas which can be accomplished with just pressure.
    • credit_guy 5y ago
      H2 is not a greenhouse gas. The leak of H2 does not contribute to global warming.
      • rrrrrrrrrrrryan 5y ago
        If you burn a greenhouse gas to create H2, and then X% of the H2 goes to waste through leakage, it's possible this process may contribute more to global warming than just transporting and burning the greenhouse gas itself, depending on X. If X is very large, you could argue that the leak of H2 does contribute to global warming.
  • JimTheMan 5y ago
• whazor 5y ago
  There are many use cases for hydrogen, the following diagram shows a ladder of competitiveness: https://pbs.twimg.com/media/E81j2loXEAYzjo5?format=jpg&name=large https://pbs.twimg.com/media/E81j2loXEAYzjo5?format=jpg&name=...
• twic 5y ago
  > If it is produced from e.g. methane (the blue version), then we are burning more methane than we would have if we had been using the methane directly Yes, but since we're capturing the CO2, that's fine. There's also turquoise hydrogen [1] - produced from natural gas by pyrolysis, capturing solid carbon, without ever producing CO2. This is equivalent to blue hydrogen, but the technology looks a lot more promising to me, because solid carbon is easier to sequester than CO2. The big problem with natural gas is the losses of the gas itself during production and transport. This is only 1-3% of the gas produced, but methane is a very powerful greenhouse gas, so even that amount is significant. If that could be substantially reduced, turquoise hydrogen looks pretty good to me. Something i haven't been able to find out is how much the loss rate varies. Maybe it's 2% on average because losses from old Russian gas wells are 5% and losses from modern North Sea gas wells are 0.1%. That would also change the picture. > we are wasting electricity that could have been used directly in BEVs It's vital to understand what hydrogen would be used for. The most important use i can see is substituting for natural gas in legacy domestic heating. There are over 20 million gas boilers in homes in the UK. We are slowly replacing them with heat pumps, electric heating, and better insulation, but it will take decades to replace them all. If we could replace natural gas in the supply with hydrogen [2], we could cut emissions much sooner - even faster than waiting for electric cars to displace petrol ones. [1] https://spectra.mhi.com/achieving-net-zero-what-is-turquoise-hydrogen https://spectra.mhi.com/achieving-net-zero-what-is-turquoise... [2] https://www.hy4heat.info/ https://www.hy4heat.info/
• mojomark 5y ago
  > end of the day, hydrogen is always going to cost more than the energy source that was used to produce it. What your failing to account for is a.) the fact that Hydrogen (and Oxygen) used with fuel cells is effectively a battery, and b.) all batteries use more energy to charge than the amount of retractable energy, c.) we accept these energy losses (costs) in the battery charging process because we need batteries for most mobile applications (not subways & similar though, these are connected to the grid). H2 and other batteries (including oil itself) are a means of making energy portable so that you don't have to plug into the grid. If we could pluge everything into the grid, then yes you're correct, H2 energy storage would only be useful for back up grid or grid buffer energy storage. For stationary applications, it doesn't make much sense to have batteries (H2 or Electric, or otherwise) since, as you state, you can just connect to the electric grid and avoid battery charging losses (unless your worried about grid instanility). However, for mobile applications (cars, ships, planes, etc), now you need to consider how to store energy off of the grid in a manner that is COMPACT and LIGHT, because these factors greatly effect vehicle transport efficiency. Oild is still king in terms of volumetric energy desnity and specific (mass) energy desnity. An energy capacity equivalent Li-ion battery is still relatively much heavier and takes up more space (meaning your vehicle will be less energy efficient). H2 storage has the potential to exceed oil in terms of volumetric/specific energy density, but it's not there just yet.* *Note that, the other component in the energy storage race isn't just the storage media, but the energy conversion efficiency of devices that use these media. For example, most common fuel cells are roughly 50% efficient in terms of the energy usage, but if you can make a fuel cell 90% efficient, then that makes the use of H2 as a battery, much more competitive. The same is true about oil burnjng engine efficiencies. Electric batteries and motors are very efficient at converting energy, however, electric batteries are currently much less energy dense than H2 or oil systems. Oil is effectively a battery that has been charged naturally by the sun (as with most mined chemical energy storage). If you create oil in a lab, you are storing the reaction energy for later use, just like charging any battery. When you charge a battery, because batteries follow the laws of thermodynamics, you always invest more energy to charge that you get out of them. Mined oil is cheap energy because it's already "charged". However, if you were to capture the waste emissions from the atmosphere and recombine them, the energy lost in the recombination would be far greater than that which you can extract when you burn it again. If someone had a way to economically capture oild emissions, then recombine the into oil - and if this process is cheaper that liberating H2 from water.
• akomtu 5y ago
  Hydrogen as a liquid fuel has no future, but hydrogen as a battery of some sort might be the solution to weak lithium batteries. I remember a post on HN talking about a special form of crystal oxygen that's filled with hydrogen atoms. That kind of thing might be an efficient battery.