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CH4 w/ H2 Blend 2

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While gently ignoring the source of the hydrogen.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
While the source of the hydrogen is not explicitly stated, as you may remember the use of hydrogen as a future fuel source is typically proposed in conjunction with renewable energy sources being used to produce the H2. Since both are included in the description of the project, it is logical to assume that is Firstgas' intent here.

 
I thought I'd read right through the proposal and didn't see a hydrogen source mentioned.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Hard to think of the article as anything other than fluff. This post at Catallaxy Files has a bit more substance. I haven't done the numbers, but I don't find them encouraging.

The referenced GE paper is not at the link, but I have attached it.

If only we had some hydrogen :)

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
 https://files.engineering.com/getfile.aspx?folder=ccd6d6bf-b0b8-4fcd-a45d-a7d0334932e8&file=GEA33861_-_Fuel_Flexible_Gas_Turbines_as_Enablers_for_a_Low_Carbon_Energy_Ecosystem.pdf
Catallaxy also says the Tx grid problem was caused by wind turbines, rather than unavailability of the gas turbine generators. The $6/kg cost is also questionable. Where did that come from? U.S. Department of Energy cost targets are $3.10/kg for central hydrogen plants and $3.70/kg for distributed hydrogen plants.

On the other hand, GE says their gas turbines will run on H2 blend. Not much of a stretch there.

 
Texas grid articles by different authors...

Don't know where the $6 comes from, author cites "a number of places". Australian dollars I assume, though not explicitly stated.

To me the figure of interest is the net power output. Again, assuming the authors numbers, 188 MW in, 34 out. Hydrogen "economy".

The problem with sloppy work is that the supply FAR EXCEEDS the demand
 
In parts of the UK they are generating H2 via electolizers using wind turbines. The electrolizers don't care about fluctuating power levels. They are blending 10% into NatGas distribution lines.
I am working on an industrial project where they will have both wind and solar power all feeding the electrolizers. Basically using H2 as a storage system. H2 is used in the process so we may end up not even burning any of it.
Lots of investment, very little operating cost.
Hitachi has been running land based turbines on 100% H2 for a couple of decades.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
 
So Firstgas didn't mention a hydrogen source? Point made.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Does anyone want to talk about how Hydrogen slowly and eventually attacks all carbon steel ?.... No ????? .... Wrong Forum ???

Is a "little bit" of pipeline Hydrogen cracking risk acceptable to the public ? .... Lets talk with the Nuclear Power people about getting the public to accept a "little bit" of risk for vast long term benefit


Nothing is easy ....

It's fun to talk about substituting H2 for Methane and using existing carbon steel pipelines and infrastructure .... makes things feasible and cheap !!!

.......and, of course you will not lose any of the precious hydrogen through pipe flange gaskets or valve stems that were originally selected to transport the big and heavy molecules of Natural Gas ..... Right ???? ..... Right ????

..... and when you store Hydrogen, you have to compress it and the gas temperature increases !!! thereby, you have increased the Hydrogen threat for cracking somewhere in the system.

We currently do not store NAT gas/methane in pressure vessels .... storage is done at the gas well. Will we not have to design, specify and construct fairly massive Hydrogen Compression and Storage facilities across the country ? ..... no Comments ?????

Who will want to live near these potential "Bombs" ??

What about the increased cost for inspection of existing Nat Gas piping systems that have been repurposed for mixed gas ?...... Don't they require additional periodic inspection to determine the amount of dangerous cracking induced by Hydrogen ?

Oh, wait !!!.... I forgot ..... we will soon have massive numbers of newly-minted STEM ENGINEERS available to solve these problems ....

(former hamburger flippers, sure .... but young and enthusiastic none the less)

Anybody have anything here on what is practical (and what is not) ??

?????????



MJCronin
Sr. Process Engineer
 
Distribution pipelines leak quite a bit of methane. More than they should, but nobody is doing much about it until they take out a city block or two. The pipeline insurance companies pay up and keep on letting them get away with it. I have written my senators and others urging better design, operation and maintenance requirements be introduced into law. Please do the same. You can include adequate credentials, experience and professional engineer only designer qualifications as a requirement exactly as I have recommended to keep the MBA well and away from the work.

The biggest problem with H2 in the current systems is keeping it out of the welds during pipe fabrication and assembly. As your link states, H2 is not usually adsorbed by steel, unless high temperatures make it possible, ie during welding. Other than that, pipelines operate at low temperatures. H2 induced stress corrosion cracking is problematic for high pressure pipelines, but the risk is supposedly small for well designed, maintained and routinely inspected pipeline systems. The problem has been adequately controlled for the most part with improvements in pipe fabrication techniques since the 80's. As for the rest, ASME B31.12, Hydrogen Pipeline Design, which I have not had occasion to read yet, surely will adequately address that well known issue to keep risk within acceptable levels, at least for the pipeline industry. Blending H2 with methane should reduce the risk further. The use of flanges in Cross Country pipelines is undesirable for many reasons, so much of that risk will be confined to stations and company properties, although there will be some additional leakage at valve stems at intermediate shut down valves. I imagine that ASME would not be wasting their time with developing B31.12, if any of them thought the result would not be acceptable for intended purpose. At this time, I am not aware of any company that is proposing that H2 actually be piped through the city for domestic use, but there are some studies and trials going on that probably will consider that service. Firstgas does envision this by 2050.



Pipeline engineering specialist contractor Penspen, is working on H2 quality and integrity monitoring now.

If you get your hands on a B31.12, please let us know if that adequately addresses your concerns.
 
That $6/kg is inceed strange. If they are making H2 with renewable power, as the Catallexy article confirms, why would they need to buy H2 at market price? The cost of H2 is already included in the cap/op/ex of the project and there is no need to buy the H2 at additional cost.

It would also appear that the author is not aware of the low temperature H2 gen process that can be run at a far lower energy cost.
 
$6/kg seems wildly optimistic according to Note these prices are in Australian dollars,

Our evaluation of the current and future (2030) cost of hydrogen from PV and electrolysis shows
that the potential cost using currently available technology is approximately $18.70/kg H2. The
base case system consists of a PV module with power electronics connected to a proton exchange
membrane electrolysis plant, which produces hydrogen only when the PV system is producing
power. The assessment is based on an estimated system cost of $2300/kW for a large scale, nontracking PV system with a mid-range capacity factor of 20.5% and a weighted average cost of
capital of 6.4%, as recently published by the CO2CRC (2015). It is assumed that the uninstalled cost
of the electrolyser and associated components is $2,285/kW, in line with recent estimates from
the European Fuel Cell and Hydrogen Joint Undertaking (Bertuccioli et al., 2014). Significant cost
reductions are predicted for both these technologies, cutting the estimated cost of hydrogen to
$9.10/kg by 2030.
The study also examined the potential of battery storage to reduce the cost of hydrogen
production. In this scenario, the battery system was used to condition the power supply from the
PV system, with sufficient storage capacity provided to enable continuous operation of the
electrolyser. Lithium-ion battery technology was selected as the most appropriate. In both current
and future scenarios, battery storage increased the cost of hydrogen relative to the base case, due
to its relatively high cost compared with energy production from PV. Based on current and future
battery costs of $540 and $200/kWh, the estimated cost of hydrogen was $28.40 and $11.30/kg in
2015 and 2030 respectively.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
For ambient temp/intermediate pressure service most pipeline steels are very content with hydrogen being used.
Some very old steels may have more issues.
High pressure and/or temp is much more problematic.
Likely the only utility with more leaks than gas distribution is water. It is a travesty that NatGas systems are so generally poorly maintained.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed
 
GregLocock said:
So Firstgas didn't mention a hydrogen source? Point made.
Click to expand...

Please tell me they're not getting the hydrogen from steam reforming ... with methane input.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
MJCronin said:
Oh, wait !!!.... I forgot ..... we will soon have massive numbers of newly-minted STEM ENGINEERS available to solve these problems ....
Click to expand...

Relax, there's an app now for practically anything. Toilet paper, clean drinking water, world peace...

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
hydrogen from steam reforming is not the plan.

 
I hear that "STEM" is being considered elitist and there's a move to change it to "STEAM" (or just "edukayshun").

Maybe that could provide a feedstock of H2 (and solve another problem at the same time) ?

another day in paradise, or is paradise one day closer ?
 
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