# What's the holdup on green hydrogen? **URL:** \ **Category:** Factual Questions\ **Created:** [August 4, 2021, 7:30am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018 "2021-08-04T07:30:17Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 4, 2021, 7:30am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/1 "2021-08-04T07:30:18Z")
Green hydrogen is hydrogen produced by electrolysis of water, where the electricity comes from renewable sources such as solar panels or wind turbines. While there may be some being produced now, it’s just small potatoes. The hydrogen used to run the buses and cars at the Olympics, for example, is actually grey hydrogen[\*]. I assume that the reason green hydrogen is not being generated much is the cost (everything comes down to cost). Renewable energy is now usually cheaper than FF energy, so it probably is not the cost of power. So what is it that’s making it cost so much? What are the technical issues? I read a lot about renewable energy and related topics, but no one ever discusses what the problem is with green hydrogen. . [\*] You may have heard that those Olympic vehicles are running on blue hydrogen.[\*\*] Don’t be fooled. Blue hydrogen doesn’t exist. It’s fraudware that’s mostly being used to delay the EV market, but also (of course) to separate fools from their money. [\*\*] Despite being colorless, hydrogen nowadays comes in many [different colors](https://www.nationalgrid.com/stories/energy-explained/hydrogen-colour-spectrum). ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [August 4, 2021, 7:37am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/2 "2021-08-04T07:37:12Z")
This Wiki article on green hydrogen: [Green hydrogen - Wikipedia](https://en.wikipedia.org/wiki/Green_hydrogen) Goes into detail as to what different countries are doing regarding green hydrogen and what future plans are. Does it help at all? ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 4, 2021, 7:42am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/3 "2021-08-04T07:42:36Z")
Not at all. I’m looking for technical details about why green hydrogen is so expensive. It doesn’t go into that at all. ---
**Author:** ![Czarcasm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/czarcasm/32/4050_2.png) [@Czarcasm](https://boards.straightdope.com/u/Czarcasm)\ **Post date:** [August 4, 2021, 7:55am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/4 "2021-08-04T07:55:02Z")
This article [Why we need green hydrogen (techxplore.com)](https://techxplore.com/news/2021-01-green-hydrogen.html) goes into detail about the challenges and cost of green hydrogen. “The problem is that green hydrogen currently costs three times as much as natural gas in the U.S. And producing green hydrogen is much more expensive than producing gray or blue hydrogen because electrolysis is expensive, although prices of electrolyzers are coming down as manufacturing scales up. Currently, gray hydrogen costs about €1.50 euros ($1.84 USD) per kilogram, blue costs €2 to €3 per kilogram, and green costs €3.50 to €6 per kilogram, according to a recent study.” The bad news is: "Friedmann believes there will be substantial use of green hydrogen over the next five to ten years, especially in Europe and Japan. However, he thinks the limits of the existing infrastructure will be reached very quickly—both pipeline infrastructure as well as transmission lines, because making green hydrogen will require about 300 percent more electricity capacity than we now have. “We will hit limits of manufacturing of electrolyzers, of electricity infrastructure, of ports’ ability to make and ship the stuff, of the speed at which we could retrofit industries,” he said. “We don’t have the human capital, and we don’t have the infrastructure. It’ll take a while to do these things.” Many experts predict it will be 10 years before we see widespread green hydrogen adoption; Friedmann, however, maintains that this 10-year projection is based on a number of assumptions. “It’s premised on mass manufacturing of electrolyzers, which has not happened anywhere in the world,” he said. “It’s premised on a bunch of policy changes that have not been made that would support the markets. It’s premised on a set of infrastructure changes that are driven by those markets.” ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [August 4, 2021, 8:13am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/5 "2021-08-04T08:13:00Z")
Electrolysis of 1 kg hydrogen requires 39.4 kWh of electricity at 100% efficiency. Even the very cheapest solar power is about $0.03/kWh, which would make the hydrogen cost $1.18/kg. That’s roughly on par with existing steam reformation. But you don’t get 100% efficiency, you get 70-80%. And the cost of electricity isn’t going to be that low in practice; it’s very likely to be 5-6¢/kWh. And the capital costs are high due to the sophisticated equipment, and it’s amortized more poorly if you’re using intermittent power like solar (or you use batteries, which add even more cost). So, best-case scenario it’s basically on par but requires intense development to reach that point. Which of course means that without subsidies or charging for externalities (carbon tax/credits), we shouldn’t expect anyone to voluntarily put in the effort. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 4, 2021, 9:02am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/6 "2021-08-04T09:02:23Z")
> [@Dr.Strangelove](#): > > the capital costs are high due to the sophisticated equipment, What kind of sophisticated equipment is it? I remember doing an electrolysis experiment way back in high school chem lab and all we did was stick a couple electrodes in water. I can see that it probably requires special electrodes because the oxygen will corrode ordinary ones. What other things make the equipment expensive? ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [August 4, 2021, 9:11am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/7 "2021-08-04T09:11:11Z")
> [@dtilque](#): > > I remember doing an electrolysis experiment way back in high school chem lab and all we did was stick a couple electrodes in water. The efficiency of just sticking electrodes in water is terrible. Most of the energy just goes into heating the water through resistive losses. If you want most of the energy to go into breaking chemical bonds you need much more extreme conditions, and you need to manage the energy very carefully, otherwise losses creep in everywhere. High temperatures and pressures are a start. That suddenly becomes a whole new world of cost. There are some really difficult issues with managing a hydrogen infrastructure. One problem rarely discussed is the terrible volumetric energy density. The idea that you can re-purpose existing natural gas infrastructure for hydrogen is simply fanciful. There is a trial gong on here diluting natural gas with hydrogen. The result is that the hydrogen is so energy poor for the amount of space it takes up relative to the natural gas that you might as well have added an inert gas to the mix. Infrastructure solutions are needed before the market can exist. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [August 4, 2021, 9:11am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/8 "2021-08-04T09:11:40Z")
It’s easy to do at low efficiency. But higher efficiencies need more advanced materials, such as PEM membranes: > **[Polymer electrolyte membrane electrolysis](https://en.wikipedia.org/wiki/Polymer_electrolyte_membrane_electrolysis)** > > Pages for logged out editors learn more > > Polymer electrolyte membrane (PEM) electrolysis is the electrolysis of water in a cell equipped with a solid polymer electrolyte (SPE) that is responsible for the conduction of protons, separation of product gases, and electrical insulation of the electrodes. The PEM electrolyzer was introduced to overcome the issues of partial load, low current density, and low pressure operation currently plaguing the alkaline electrolyzer. It involves a proton-... Sorta like a reverse fuel cell. And generally speaking, we’re talking a lot of electrical energy here. It needs conductors and power regulators and all that stuff. Chemical processes can often handle high energies much less expensively. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [August 4, 2021, 9:26am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/9 "2021-08-04T09:26:19Z")
OK, thanks for the info, both of you. Looks like we need to be investing more in turquoise hydrogen rather than green. Turquoise is hydrogen produced by pyrolysis of methane: > **[Decarbonizing Natural Gas: Methane Fuel without Carbon Dioxide - Advanced...](https://www.advancedsciencenews.com/decarbonizing-natural-gas-methane-fuel-without-carbon-dioxide/)** > > A fascinating approach for utilizing the chemical energy contained in the carbon–hydrogen bonds of methane without the co-production of carbon dioxide in the combustion process is discussed. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [August 4, 2021, 11:47am UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/10 "2021-08-04T11:47:50Z")
> [@dtilque](#): > > The hydrogen used to run the buses and cars at the Olympics One problem you face is that if your goal is to run buses and cars, hydrogen is definitely not your best choice. If your ultimate source of power comes from electricity, you are much better off making electric vehicles. Nothing is 100 percent efficient, but electric vehicles convert about 70 to 80 percent of the energy into motion. If you take your electricity and use it to generate hydrogen, you lose about 20 to 30 percent of your energy just in that process. If you had a magic hydrogen vehicle that converted 100 percent of the energy from hydrogen into motion, you’d be fairly close to breaking even with an electric vehicle. But that magic vehicle doesn’t exist. You can use hydrogen fuel cells, but that loses about 50 percent of the energy from your hydrogen, and fuel cells have a whole bunch of practical disadvantages as well. You could use an internal combustion engine, but that only converts about 30 percent of the energy from your hydrogen into motion. The rest goes into waste heat. If your goal is to make cars and buses move using the energy from solar panels and wind farms, you’ll need about twice as many solar panels and wind turbines if you want to use hydrogen instead of electric vehicles. This makes me doubt that we’ll see widespread hydrogen adoption in the next 10 years, and without widespread adoption, you aren’t going to get the huge infrastructure investment required to make gains from economy of scale and efficient processes that require a large up-front investment. ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 4, 2021, 1:22pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/11 "2021-08-04T13:22:10Z")
> [@engineer\_comp\_geek](#): > > One problem you face is that if your goal is to run buses and cars, hydrogen is definitely not your best choice. If your ultimate source of power comes from electricity, you are much better off making electric vehicles. It depends where you’re generating the electricity and whether and how long you need to store it. The vehicles in question are in Japan, which intends to import energy as hydrogen or ammonia, which while lower-efficiency to make is cheaper to move and store. ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 4, 2021, 2:09pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/12 "2021-08-04T14:09:36Z")
Re: production cost, I have a local copy of some slides from Sunita Satyapal (director of DOE HFTO) showing a system cost of $800-1500/kW. They’re aiming for $250-300/kW, although much of that is expected to be from typical scaling cost reductions. There were less than 100 MW of electrolyzers installed until recently, but there are now over 40 GW planned, so that should help with economies of scale. Balance of Plant (cooling, gas processing, water circulation, power electronics) actually costs more than the stack. That’s all aside from hydrogen storage (which still kind of sucks IMO) and use, but those are both independent of the color of hydrogen. I’ll see if those slides are posted anywhere. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [August 4, 2021, 3:17pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/13 "2021-08-04T15:17:24Z")
> [@Ruken](#): > > Re: production cost, I have a local copy of some slides from Sunita Satyapal (director of DOE HFTO) showing a system cost of $800-1500/kW. > . > . > . > I’ll see if those slides are posted anywhere. Maybe here? [https://www.hydrogen.energy.gov/amr-presentation-database.html](https://www.hydrogen.energy.gov/amr-presentation-database.html) Searching for “satyapal” there brings up seven entries. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [August 4, 2021, 3:42pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/14 "2021-08-04T15:42:59Z")
Besides cost and efficiency, there is the issue of storage. It’s just hard to store that stuff in quantity. So it’s like 3 strikes against it at this point. Now if we can get very cheap energy, dirt cheap, then the storage issue may become something we can live with. For instance, if solar and wind create such excess power at times that on one can use or store, it might be the thing to do is convert water into hydrogen fuel then let it go to waste. However there is competing technologies such as conversion of CO2 and water to methanol that are more efficient and also ‘green’, as the CO2 comes from the air, so the carbon containing fuel it creates is carbon neutral. Iceland has some projects going of this type, do to their abundant geothermal power with the goal of selling the methanol as a motor fuel additive for the rest of Europe (as Iceland itself move slowly towards an expected all electric mode of vehicles, do to their cheap power). As compared to hydrogen, methanol has several advantages as it can go into much of the existing infrastructure of ICE’s. ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 4, 2021, 4:04pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/15 "2021-08-04T16:04:34Z")
> [@kanicbird](#): > > as the CO2 comes from the air, so the carbon containing fuel it creates is carbon neutral. Iceland has some projects going of this type, do to their abundant geothermal power Although CRI’s George Olah plant actually uses CO2 that comes up with the geothermal steam, so no air capture in this case unless there’s another plant I’m not aware of. Same chemistry though if you hooked it up to DAC. And it’s still water electrolysis to get the hydrogen for the methanol – they’re just not moving the hydrogen. ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 4, 2021, 4:08pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/16 "2021-08-04T16:08:54Z")
> [@Machine\_Elf](#): > > Maybe here? > [Annual Merit Review Presentation Database | Hydrogen Program](https://www.hydrogen.energy.gov/amr-presentation-database.html) > > Searching for “satyapal” there brings up seven entries. Close enough. I might have a draft, but this works: > **[plenary5\_satyapal\_2021\_o.pdf](https://www.hydrogen.energy.gov/docs/hydrogenprogramlibraries/pdfs/plenary5_satyapal_2021_o.pdf)** > > 8.24 MB ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [August 4, 2021, 4:35pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/17 "2021-08-04T16:35:00Z")
Remember solar only produces electricity when the sun is shining (and solar produces about 3 times as much electricity in the longest summer days than the shortest winter days in Minnesota) and wind only produces electricity when the wind is blowing. Yet consumers demand electricity 24 hours a day, seven days a week. There are three basic renewable ways to deal with this issue (massive overcapacity of generating capacity, storage and a massive electric grid moving electricity around the country). If you use massive overcapacity then you have a great deal of free electricity (otherwise it is just thrown away or the generators disconnected) which you could use to generate green hydrogren. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [August 4, 2021, 4:38pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/18 "2021-08-04T16:38:11Z")
> [@Ruken](#): > > Although CRI’s George Olah plant actually uses CO2 that comes up with the geothermal steam, so no air capture That CO2 was destined to end up in the just air moments after it was captured for this process. So yes practically speaking it acts as air capture. The process could also use atmospheric CO2, however it makes sense to use the higher concentrations of CO2 in the vents. ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [August 4, 2021, 4:50pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/19 "2021-08-04T16:50:44Z")
> [@kanicbird](#): > > So yes practically speaking it acts as air capture. No, it does not. It’s a point source, not air. Air is harder. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [August 4, 2021, 4:58pm UTC](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018/20 "2021-08-04T16:58:03Z")
> [@Ruken](#): > > No, it does not. It’s a point source, not air. Air is harder. OK, (and yes I said air is harder in my post), but yes your absolutely positively right, in this process there is less CO2 emitted in the air, thus reducing an ongoing continuous input to atmospheric CO2. And thus acting exactly like it was removing atmospheric CO2 from the air from the POV of global CO2 levels in the air. [Next page](https://boards.straightdope.com/t/whats-the-holdup-on-green-hydrogen/948018.md?page=2)