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Hydrogen Capable Natural Gas Turbines

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8 minutes ago, BradleyPNW said:

If we emphasize cost I don't think we wind up with green CH4. 

 Green NG never gets an opening because it was competing with fossil NG. 

 

Green CH4 cannot compete with the current below-cost NG. That NG is a waste product of oil production in the Permian. When Permian oil is exhausted (probably after 2025 and before 2030) NG prices will rise to the production costs in other areas. In the mean time the cost of green CH4 will drop both because the cost of wind and solar electricity drops, and because of technological advances. Solar and wind, and green CH4 have high capital cost and exceptionally low operating costs. We will see how this all works out.

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On 5/21/2020 at 5:45 AM, nsdp said:

You are only about 15 years out of date.   Today's wind prices prodcue H2 under $2/kg

Hydrogen hydrolyzers have very bad efficiency. Cheapest at 33%. And fanciest around 50%. Lets say we have some fancy and expensive hydrolyzer at 50% efficiency we need to have electricity price at 1,5 cent per kWh to produce 2kg hydrogen. We exclude expenses of cleaning input water and output hydrogen and also hydrogen compression energy.

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On 5/21/2020 at 6:34 AM, NickW said:

You can actually burn Ammonia in a diesel engine with only minor modifications. Not sure about its use in turbines but it has been used as a rocket fuel. 

My point is that until supply is such that there is a surplus better to divert H2 into processes where it is most efficiently used. Using it to make Ammonia saves far more natural gas than converting it Methane. 

More importantly, it is much easier and safer to transport H in ammonia. That is what Australia about to do. That is our plan to send our green H to Japan and SK.

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8 hours ago, entertenter said:

Hydrogen hydrolyzers have very bad efficiency. Cheapest at 33%. And fanciest around 50%. Lets say we have some fancy and expensive hydrolyzer at 50% efficiency we need to have electricity price at 1,5 cent per kWh to produce 2kg hydrogen. We exclude expenses of cleaning input water and output hydrogen and also hydrogen compression energy.

Sounds on the low side

https://www.chemeurope.com/en/encyclopedia/Electrolysis_of_water.html

The energy efficiency of water electrolysis varies widely. Some report 50–70%[1], while others report 80–94%.[2] 

 

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2 hours ago, Wombat said:

More importantly, it is much easier and safer to transport H in ammonia. That is what Australia about to do. That is our plan to send our green H to Japan and SK.

Ocean transport of ammonia, at large scale, has apparently been around for a very long time. Here is a paper from 1977:

https://link.springer.com/chapter/10.1007/978-94-017-1538-6_7

and in 2005 the US imported about 40% of its ammonia:

https://nh3fuel.files.wordpress.com/2012/05/chemicalmarketingservices.pdf

But since at least 2015 the US is a net exporter:

https://www.ustradenumbers.com/export/ammonia/

Almost all of the ammonia is used to produce fertilizer. That's good, because ammonia for fertilizer currently consumes more that 5% of the total NG production. Since this ammonia transportation infrastructure is already in place, there is no need to pay for an entire new one. Until you meet this worldwide demand for ammonia, it is more cost-effective to make ammonia than it is to make CH4. The displaced NG can be used to produce electricity as usual, so the green ammonia reduces the amount of fossil CH4 being used.

But to get to 100% renewable energy, you need an infrastructure for long term energy storage and transportation that is many times larger than the existing ammonia infrastructure.  Such a system already exists. It transports, stores, and consumes CH4. I contend that this will make CH4 more attractive than ammonia for energy storage at the system level.

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9 hours ago, entertenter said:

Hydrogen hydrolyzers have very bad efficiency. Cheapest at 33%. And fanciest around 50%. Lets say we have some fancy and expensive hydrolyzer at 50% efficiency we need to have electricity price at 1,5 cent per kWh to produce 2kg hydrogen. We exclude expenses of cleaning input water and output hydrogen and also hydrogen compression energy.

Electricity==>H2 efficiencies can be as high as 72% for compresses gas or 77% if you don't count compression.

https://en.wikipedia.org/wiki/Power-to-gas

But that misses the point completely. When building wind or solar, you size it to make as much money by selling electricity as possible. But this means that there will be times when you have too much electricity to sell. This extra electricity has zero or negative cost. You store this in batteries until you fill them up, then use the rest of this zero-cost electricity  to make H2. Therefore, the cost of the H2 reduces to the amortized cost of the capital for the conversion equipment. in this arrangement, a cheaper but less efficient P2G setup might be more profitable than a more expensive but more efficient setup.

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Why not use surplus electricity to heat water? My flat in Poole (UK) is on the old Economy 7 system,giving a lower price for consumption during the night. A mixer tap can give a comfortable shower from the stored hot water. Electric instantaneous showers draw a huge current from the grid at peak demand times.

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1 hour ago, Richard D said:

Why not use surplus electricity to heat water? My flat in Poole (UK) is on the old Economy 7 system,giving a lower price for consumption during the night. A mixer tap can give a comfortable shower from the stored hot water. Electric instantaneous showers draw a huge current from the grid at peak demand times.

That is one option for people with solar panels. Get a PV immersion diverter. Any surplus electricity that would have been exported gets diverted to the immersion. If you are on a FIT you get that too. If not it just offsets whatever you normally use to heat water. 

https://solarimmersion.co.uk/

I think people with solar panels should be encouraged to get these because it reduces the flood of solar onto the grid which is potentially problematic. 

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5 hours ago, Richard D said:

Why not use surplus electricity to heat water? My flat in Poole (UK) is on the old Economy 7 system,giving a lower price for consumption during the night. A mixer tap can give a comfortable shower from the stored hot water. Electric instantaneous showers draw a huge current from the grid at peak demand times.

This works for individual homes, but not so well at utility scale. You should be using a heat pump, not resistance heater, unless the electricity is zero cost. Ideally, the heat pump would be ground-sourced.

You can also install a battery instead of a water tank. roughly the same size, but much more flexible. computing the payback time is complicated.

Do europeans still use those heat reservoirs filled with molten wax to time-shift the demand load?

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45 minutes ago, Dan Clemmensen said:

This works for individual homes, but not so well at utility scale. You should be using a heat pump, not resistance heater, unless the electricity is zero cost. Ideally, the heat pump would be ground-sourced.

You can also install a battery instead of a water tank. roughly the same size, but much more flexible. computing the payback time is complicated.

Do europeans still use those heat reservoirs filled with molten wax to time-shift the demand load?

'Economy 7' heaters are still common - mainly in apartments that use off peak electricity to heat the concrete block inside the heater and a hot water cylinder - usually at the base. 

However with smart meters you can now sign up to tarrifs that utilise cheapo electricity - sometimes you can get the power for nothing if demand is very weak. 

In general Id agree thought if using electric heat pumps is the way to go. 

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The internet reported that a new water electrolysis installation in Canada consumed 20MW of electricity to produce under 3,000 tonnes per year of hydrogen. I calculate that as around 66% efficiency of conversion. The idea would seem to be dead in the water. I agree that small PEM electrolysers may be more efficient,but the plant costs would then be off-scale.

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1 hour ago, Richard D said:

The internet reported that a new water electrolysis installation in Canada consumed 20MW of electricity to produce under 3,000 tonnes per year of hydrogen. I calculate that as around 66% efficiency of conversion. The idea would seem to be dead in the water. I agree that small PEM electrolysers may be more efficient,but the plant costs would then be off-scale.

I guess you meant 20 MWh, not 20 MW? Conversion efficiency does not matter when the input electricity has zero or negative cost. This occurs when supply exceeds demand for wind or solar, and in Canada can also occur for some hydro. The correct metric is not conversion efficiency, but is instead amortized capital cost of the electrolysis installation.

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I meant what I said;20 MW for one year.

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55 minutes ago, Richard D said:

I meant what I said;20 MW for one year.

OK, got it, thanks. This appears to be the system you are referring to:

https://www.hydrogenics.com/2019/02/25/hydrogenics-to-deliver-worlds-largest-hydrogen-electrolysis-plant/

and that article does in fact use "20 MW" and "3,000 tonnes/year", which mixes up power with energy. To make your calculation, you had to infer that the plant was going to operate 24/7 for the whole year. The article does not actually say that. I guess we need to find a technical paper on the installation.  Note that this is a PEM system, not a simple brute-force electrolyzer.

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You guys are finally getting the idea. When GE invented the PEM back in 1955 it was originally used for life support in submarines (O2). Since that time it was determined that what passes the membrane is a single proton. This is truly a quantum device and is not subject  to the laws of chemistry, because it operates on the laws of quantum mechanics.

If you attached these electrolyzers into a ISO managed power grid and allow the computer system to power source follow. Hence, when the wind is blowing produce hydrogen. You can get power contracts as low as $10Mwh from ACEs Power marketing, without storage adder. That works out to $0.60 per kg without CAPEX. With CAPEX its $1.20 per kg. Your biggest challenge will be storage.

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On 5/17/2020 at 12:39 PM, Dan Clemmensen said:

I tried to find the H2 storage capacity of the salt domes and failed miserably. The only number I found was "enough to store the energy used by 150,000 households for a year" in this "geologically rare" salt dome. Well, folks, that's not going to scale well. By comparison, California has massive underground storage for CH4 already in place and operating. Take the additional efficiency hit to convert the H2 to CH4, and then just inject it into the existing NG infrastructure at effectively zero incremental capital cost for storage, transport, and retrieval. Yes, there is new capital cost for the H2==>CH4 converters, but no need to develop. pay for, and deploy fancy new turbines or H2 storage and transport infrastructure.

See Praxair Moss Bluff Dome, Liberty County, TX. https://sway.office.com/2uoBA0J1NHyTvZrY?play

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H2 is the fuel of the future in my mind and Gas/Electric vehicles are just the stepping stone, yes plenty of things to resolve but it's moving that way.

For example Netherlands now have a law that all new housing can not have NG piped in for domestic use as they push for hydrogen

In Lancaster California they are pushing the project development of the largest Green H2 facility in the world using biofeedstock which will be a game changer.

https://www.forbes.com/sites/kensilverstein/2020/05/26/the-worlds-biggest-green-hydrogen-plant-is-underway-in-california-its-prospects-for-electric-power-and-transportation/#526bb6cd2a96

 

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(edited)

On 5/25/2020 at 1:44 AM, entertenter said:

Hydrogen hydrolyzers have very bad efficiency. Cheapest at 33%. And fanciest around 50%. Lets say we have some fancy and expensive hydrolyzer at 50% efficiency we need to have electricity price at 1,5 cent per kWh to produce 2kg hydrogen. We exclude expenses of cleaning input water and output hydrogen and also hydrogen compression energy.

I suggest you look at Giner https://www.ginerinc.com/,  ITM  https://www.itm-power.com/ and Hydrogenics https://www.hydrogenics.com// among others .  Depending on purity and pressure;  four nines purity and 200 atmospheres has been de rigour for 8 years at 85% efficiency.  If you can live with 2% H2O then 91% is the current expectation.

Edited by nsdp
correct link

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(edited)

On 5/27/2020 at 2:14 PM, Jeffrey B. Pickett said:

See Praxair Moss Bluff Dome, Liberty County, TX. https://sway.office.com/2uoBA0J1NHyTvZrY?play

I got something else. You might try  The Role of Hydrogen in a
Renewable Energy Economy by Christopher Hebling. He lists GWH capacity for Clemens Dome, Moss Bluff and Tyneside salt storage dedicated to H2.  Page. s 28-30

these arethe people who are most knowledgable on solar and H2 

Fraunhofer Institute for Solar Energy Systems ISE

Edited by nsdp

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On 5/26/2020 at 1:38 AM, Dan Clemmensen said:

Ocean transport of ammonia, at large scale, has apparently been around for a very long time. Here is a paper from 1977:

https://link.springer.com/chapter/10.1007/978-94-017-1538-6_7

and in 2005 the US imported about 40% of its ammonia:

https://nh3fuel.files.wordpress.com/2012/05/chemicalmarketingservices.pdf

But since at least 2015 the US is a net exporter:

https://www.ustradenumbers.com/export/ammonia/

Almost all of the ammonia is used to produce fertilizer. That's good, because ammonia for fertilizer currently consumes more that 5% of the total NG production. Since this ammonia transportation infrastructure is already in place, there is no need to pay for an entire new one. Until you meet this worldwide demand for ammonia, it is more cost-effective to make ammonia than it is to make CH4. The displaced NG can be used to produce electricity as usual, so the green ammonia reduces the amount of fossil CH4 being used.

But to get to 100% renewable energy, you need an infrastructure for long term energy storage and transportation that is many times larger than the existing ammonia infrastructure.  Such a system already exists. It transports, stores, and consumes CH4. I contend that this will make CH4 more attractive than ammonia for energy storage at the system level.

This is what I am talking about Dan, Australia's plan to transport green H2 in form of Ammonia to power Asian fuel cell vehicles: https://www.ammoniaenergy.org/articles/ammonias-role-in-the-hydrogen-society/    there is also this: https://www.sciencedirect.com/science/article/pii/S0360319913013761   so as you can see, there is potential for both direct combustion of Ammonia in diesel engines (which reduces CO2 emissions but not eliminate them), or take the extra step to convert Ammonia back to pure H2 (more expensive but more environmentally friendly). It is the second option that Australia is working towards (due to fact that all South Korean taxis now run on H2), but as the first article suggests, each country moving in their own direction regarding the H2 economy and ammonia often a big part of it. Hope you enjoy the reading :)

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(edited)

42 minutes ago, Wombat said:

This is what I am talking about Dan, Australia's plan to transport green H2 in form of Ammonia to power Asian fuel cell vehicles: https://www.ammoniaenergy.org/articles/ammonias-role-in-the-hydrogen-society/    there is also this: https://www.sciencedirect.com/science/article/pii/S0360319913013761   so as you can see, there is potential for both direct combustion of Ammonia in diesel engines (which reduces CO2 emissions but not eliminate them), or take the extra step to convert Ammonia back to pure H2 (more expensive but more environmentally friendly). It is the second option that Australia is working towards (due to fact that all South Korean taxis now run on H2), but as the first article suggests, each country moving in their own direction regarding the H2 economy and ammonia often a big part of it. Hope you enjoy the reading :)

Thanks. The first paper (from ammoniaenergy.com) is more recent and more practical. I makes the point that most of the research it surveys emphasizes ammonia as a way to store and transport H2, but that direct use as ammonia in its current roles (fertilizer) is more energy-efficient than converting to H2. It's also clear that this transport is intended as part of the H2 economy, with all the infrastructure that requires. So it can start making money immediately in Korea and Japan, but not so much elsewhere. The paper (from an ammonia organization) does not attempt a comparison with CH4.

This entire thread started with H2-capable turbines. I wonder if there is an analysis of NH3-capable turbines somewhere. If you are starting from NH3, according to the paper it should be more energy-efficient to just burn it than to first convert to H2.  (UPDATE: there is some research: https://www.sciencedirect.com/science/article/pii/S1540748918306345 )

(Disclaimer: I'm very cautious about ammonia. I worked in a frozen vegetable factory that had an ammonia-based freezing system with lots of high-pressure ammonia lines overhead. I saw a guy accidentally whack a raised forklift fork into a line. Didn't actually damage it, but it's the only time I've ever seen a guy literally thrown off a job. The foreman grabbed him off the forklift, carried him to the door and threw him about six feet, then sat on the ground and had the shakes because he had seen an actual ammonia accident.)

Edited by Dan Clemmensen
add a paper

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19 minutes ago, Dan Clemmensen said:

Thanks. The first paper (from ammoniaenergy.com) is more recent and more practical. I makes the point that most of the research it surveys emphasizes ammonia as a way to store and transport H2, but that direct use as ammonia in its current roles (fertilizer) is more energy-efficient than converting to H2. It's also clear that this transport is intended as part of the H2 economy, with all the infrastructure that requires. So it can start making money immediately in Korea and Japan, but not so much elsewhere. The paper (from an ammonia organization) does not attempt a comparison with CH4.

This entire thread started with H2-capable turbines. I wonder if there is an analysis of NH3-capable turbines somewhere. If you are starting from NH3, according to the paper it should be more energy-efficient to just burn it than to first convert to H2.  (UPDATE: there is some research: https://www.sciencedirect.com/science/article/pii/S1540748918306345 )

(Disclaimer: I'm very cautious about ammonia. I worked in a frozen vegetable factory that had an ammonia-based freezing system with lots of high-pressure ammonia lines overhead. I saw a guy accidentally whack a raised forklift fork into a line. Didn't actually damage it, but it's the only time I've ever seen a guy literally thrown off a job. The foreman grabbed him off the forklift, carried him to the door and threw him about six feet, then sat on the ground and had the shakes because he had seen an actual ammonia accident.)

Interesting. I know that one of the new H2 filling stations in SK had a massive explosion, but doesn't seem to have changed their minds about it. I doubt there are NH3 capable turbines, suspect the chemistry and physics not favourable, but getting back to H2-capable turbines, they are clearly the future in many countries and this will create a large global demand for H2, along with more H2 fuel-cell vehicles. Indeed, Japan would like to use Australian brown coal (in Victoria) to produce "grey Hydrogen" but use CCS by pumping the CO2 into nearby depleted NG fields in the Bass Strait. Where there is a will, there is a way! I think it was nsdp that mentioned the fact that the finance sector is turning it's back on funding ff in general, and if u have ever read Bloomberg green finance section, you will get the gist that renewable energy does not have to be the cheapest or most technically superior method in order to win the funding at expense of CH4. There are also geo-political factors at play. Consider Australian national security, for example. We are largest LNG exporter on planet, but no longer use LPG in our taxis because domestic NG no longer cheap due to World Parity Pricing. Our oil consumption has grown dramatically whilst our production has collapsed. So, from our point of view, the H2 economy will be our savior. Once the tech is mature in Japan and SK, and we are supplying large amounts of H2 (whether it be green or grey), we will then be able to import cars and trucks that run on H2. This is important because much of our trucking is very long-distance, and many Australians use their 4WD vehicles for camping, so EV's not an option. The whole oil&gas complex is becoming unsustainable on a number of fronts. True, the NG side is just entering it's "glory days" as a "bridge fuel", but don't expect it to last too long when even in the USA, many utilities are bypassing NG and going straight to wind and solar with battery storage.

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6 hours ago, Dan Clemmensen said:

Thanks. The first paper (from ammoniaenergy.com) is more recent and more practical. I makes the point that most of the research it surveys emphasizes ammonia as a way to store and transport H2, but that direct use as ammonia in its current roles (fertilizer) is more energy-efficient than converting to H2. It's also clear that this transport is intended as part of the H2 economy, with all the infrastructure that requires. So it can start making money immediately in Korea and Japan, but not so much elsewhere. The paper (from an ammonia organization) does not attempt a comparison with CH4.

This entire thread started with H2-capable turbines. I wonder if there is an analysis of NH3-capable turbines somewhere. If you are starting from NH3, according to the paper it should be more energy-efficient to just burn it than to first convert to H2.  (UPDATE: there is some research: https://www.sciencedirect.com/science/article/pii/S1540748918306345 )

(Disclaimer: I'm very cautious about ammonia. I worked in a frozen vegetable factory that had an ammonia-based freezing system with lots of high-pressure ammonia lines overhead. I saw a guy accidentally whack a raised forklift fork into a line. Didn't actually damage it, but it's the only time I've ever seen a guy literally thrown off a job. The foreman grabbed him off the forklift, carried him to the door and threw him about six feet, then sat on the ground and had the shakes because he had seen an actual ammonia accident.)

Some more articles that u may find of interest: https://oilprice.com/Alternative-Energy/Fuel-Cells/How-Long-Until-Hydrogen-Is-Competitive-At-The-Pump.html  and   https://oilprice.com/Alternative-Energy/Fuel-Cells/Is-Green-Hydrogen-The-Future-Of-Energy-Storage.html  and  https://oilprice.com/Alternative-Energy/Fuel-Cells/Green-Hydrogen-Is-Right-Around-The-Corner.html and finally https://www.flightglobal.com/airframers/all-electric-grand-caravan-makes-maiden-flight/138600.article?mod=article_inline                                                                                                                                                                                                                                                       As you can see, fossil fuels are now being attacked from all angles, whether it be electric cars, hydrogen cars, even electric or hydrogen aircraft, hydrogen shipping, batteries, pumped hydro, and hydrogen storage for electricity. You know that renewable energy produced 33% of the world electricity so far this year, more than coal. Everything changing at warp speed right now which is why I think the likes of Russia and the Middle East will be quaking in their boots within just 5 years.

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9 hours ago, Wombat said:

True, the NG side is just entering it's "glory days" as a "bridge fuel", but don't expect it to last too long when even in the USA, many utilities are bypassing NG and going straight to wind and solar with battery storage.

I love renewables and I want to get to 100% renewable as fast as possible. However, until we have long-term storage for renewable energy, we cannot do without NG (or nuclear, but nuclear simply cannot be built). We have batteries for short term storage, but they will prpbably never be cost-effective for long-term storage.  If you system must ever run for a week or more with little or no renewable electrical energy, you need long-term storage and the generators that can use it to supply 100% of the demand.

"As fast as possible" requires both a technology and a transition strategy. build-out of a new parallel infrastructure that can provide 100% of the demand for a week will in my opinion be cost-prohibitive and will take too long. Therefore, I think we should use CH4 generated from renewables for storage. This allows the use of the existing infrastructure and the existing generators, and it can be done incrementally. Each solar array and each wind farm can be fitted with an electricity==>CH4 system, and these can feed the existing system just as NG gas wells do. This means the transition is continuous and incremental, needing no unified plan and no major new infrastructure. Each renewable electrical source will also supply electricity directly when it can, and the demand will be met from this electricity first with this electricity to reduce the amount  of CH4 consumed. When there is excess renewable electricity, it will make CH4 for later use. As the current artificially-low cost of NG rises and the cost of renewable CH4 falls with improved technology and economies of scale, NG drilling will become uneconomic and the transition will be complete. In my opinion, this is the fastest possible way to get to 100% renewables.

H2 vehicles require H2 fueling stations. This can be implemented either via an H2 delivery infrastructure or by generating H2 on site at the station from renewable electricity or from renewable CH4. The relative efficiency gain from the H2 delivery infrastructure is offset by its capital cost. I have not done the math so I do not know where the break-even point lies. A station next to a renewable source might use H2 directly, a station connected to a CH4 pipe might use a convertor, and a station in the middle of nowhere might use electricity. I think that most vehicles will be EV, but a few will need the high energy density and high refueling rate equivalent to today's ICEs. I don't know that H2 is the most appropriate. It's possible that liquid fuel synthesized from electricity will work better. This will almost certainly be the case for aircraft.

Note that an H2 station with its own electricity==>H2 system can make and store H2 when the grid is currently sourcing renewable electricity and (almost) never when the grid is running on storage. This is more efficient than running through the various conversion. the same would be true for a station making its own liquid fuel. There is currently a demo making jet fuel from electricity at an airport in the Netherlands.

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17 hours ago, nsdp said:

I suggest you look at Giner https://www.ginerinc.com/,  ITM  https://www.itm-power.com/ and Hydrogenics https://www.hydrogenics.com// among others .  Depending on purity and pressure;  four nines purity and 200 atmospheres has been de rigour for 8 years at 85% efficiency.  If you can live with 2% H2O then 91% is the current expectation.

Umm...Where is this "efficiency"?  And no, you do not get 200bar for free... There is no way in this world to get 200bar and 85% efficiency.  If there was, every single pump and turbine around the world would be changed out YESTERDAY.  In fact if it was 1bar and 85% efficiency, every pump and Turbine around the world would be changed to take advantage of the new physics. 

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