33
Victoria warned against ‘very inefficient’ hydrogen buses after trial announced
(www.theguardian.com)
this post was submitted on 24 Nov 2023
33 points (100.0% liked)
Melbourne Trains
247 readers
8 users here now
About
c/MelbourneTrains is a community dedicated to all forms of public transport within the state of Victoria, Australia. We are a friendly and helpful community that welcomes anybody with an interest in Victoria public transport.
Rules
This community operates under the rules of aussie.zone. These apply to you regardless of which instance you are interacting from.
Credits
Community icon by @[email protected] featuring a W8 Class tram taken on April 17, 2022. Community banner by @[email protected] in the style of former Metropolitan PTV Platform sign. (aussie.zone icon in the community banner cleaned up by @[email protected].)
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
@WaterWaiver @AllNewTypeFace There's a perception that we could just reuse existing methane gas (i.e. "natural gas") infrastructure for hydrogen. But often that just isn't the case:
"The pipelines that transport hydrogen are made of the same basic material as most of those built for natural gas: steel. But hydrogen is a much smaller molecule than methane, the main component in natural gas. In fact, hydrogen is the smallest molecule on Earth. Its size means it can squeeze into tiny spaces in certain steel alloys in a way that natural gas cannot. That can cause “embrittlement,” making the metal more likely to crack or corrode. Hydrogen molecules are also much more likely to leak from valves, seals, and other connection points on pipelines (which risks undermining green hydrogen’s climate benefits). And hydrogen is transported in a more pressurized state than natural gas, which puts more stress on the pipeline carrying it.
"Rather than transporting 100 percent hydrogen, many companies are now testing whether they can blend hydrogen with natural gas for transport in existing pipelines. In a study released last summer, the California Public Utility Commission found that up to 5 percent hydrogen blended with natural gas appears safe, but higher percentages could lead to embrittlement or a greater chance of pipeline leaks. Internationally, France places the highest cap on hydrogen blending, at 6 percent, according to the International Energy Agency (Germany allows blending at 8 percent under certain conditions)."
Source: https://climate.mit.edu/ask-mit/can-we-use-pipelines-and-power-plants-we-have-now-transport-and-burn-hydrogen-or-do-we-need
If the aim is to reach net zero emissions by 2050, a 90% or 95% methane to 10% or 5% hydrogen gas blend just isn't that useful for reaching that goal.
(And that's assuming the hydrogen is green hydrogen as well.)
And if a lot of your infrastructure has to be retrofitted anyway, electrification plus renewables plus storage makes a lot more sense in many cases.
There are still use cases where green hydrogen will be useful — international long-haul flights, rockets, some industrial processes, etc. But it's not the best solution in most cases.
#ClimateChange #hydrogen #gas #NetZero #electrification #transport
Thankyou for that info. I knew it was leaky, but I didn't realise that pipeline materials were so incompatible.
@WaterWaiver @ajsadauskas Even if the pipelines were not, as a software engineer I don't get how you get past the incompatible end user appliances in domestic and industrial sectors.
You can get to that 5%, and an ongoing 5% drop is a little helpful, but how do you swap every single gas appliance?
How do you ensure that every single appliance on a network branch is compatible at scale?
You can not do a flag day, surely, but how do you change a stove from one jet to another at the right time?
You're focusing only on (1) consumer usage and (2) fixed pipelines. There is a bigger variety of gas infrastructure than that.
@ajsadauskas
Thanks for sharing this information.
Still it seems to be more economical to use existing pipelines than new ones. Also a polymer coating is an option.
@WaterWaiver @AllNewTypeFace
https://www.energy.gov/eere/fuelcells/hydrogen-pipelines
https://www.siemens-energy.com/global/en/home/stories/repurposing-natural-gas-infrastructure-for-hydrogen.html
@ajsadauskas @WaterWaiver @AllNewTypeFace @25kV
maybe, if climate change was taken seriously already 25 years ago, non-negligible share of principal gas infrastructure could have been hydrogen-ready by now...
You're just spreading propaganda against hydrogen. It is fundamental to a zero emissions society. It is even necessary to get the grid to zero emissions. Nearly all rhetoric against hydrogen is just some kind of corporate propaganda, if not from the battery industry then it is from the petroleum industry.
Hydrogen is essential, but we need it for the chemical industry, steelmaking, etc. Using hydrogen as an incredibly expensive and inefficient battery by turning it back into electricity is not the future.
@zurohki @Hypx Given the ability to build pretty large hydrogen or ammonia tanks, would it scale better than dams or chemistry for week-plus durations?
Depends on how much they cost. Since hydrogen energy storage means throwing away 2/3 of the energy you generate, it's not a viable option unless it's massively cheaper or batteries just can't do the job at all.
Yes, that's the point. The problem of batteries is that you need to mine a vast amount of raw materials for them. So it doesn't even matter how much "better" they are. It is simply not an answer no matter what.
@Hypx @Baku @AllNewTypeFace @WaterWaiver @ajsadauskas @zurohki A lot to be said for low capex / high opex in some of these cases.
@abartlet @Hypx @Baku @AllNewTypeFace @WaterWaiver @zurohki In the context of Melbourne, around 2 million Victorian households currently use methane ("natural") gas appliances: https://www.theage.com.au/national/victoria/renters-low-income-households-left-behind-in-race-to-turn-off-gas-20230724-p5dquv.html
Last year, the Victorian state government mandated that new homes and buildings are fully electrified: https://www.theage.com.au/politics/victoria/gas-connection-to-be-banned-from-new-homes-in-victoria-20230728-p5dryd.html
Here's the state government's media release: https://www.premier.vic.gov.au/new-victorian-homes-go-all-electric-2024
Up until the mid '90s, that gas supply was provided through a state government agency called the Gas & Fuel Corporation. As with many things in Victoria, it was privatised in the mid 1990s by former premier Jeff Kennett.
Here's all the consultation papers: https://engage.vic.gov.au/help-us-build-victorias-gas-substitution-roadmap
Not surprisingly, the gas industry came out heavily against a mandate to ban the installation of new gas appliances.
This from the Australian Gas Association submission: https://engage.vic.gov.au/download/document/17468
"Electrification of the current energy system will be next to impossible if the source is to be
renewable wind, solar and hydro. Natural gas/hydrogen will play a huge role in helping Australia pivot into systems that reduce emissions."
From the gas energy association: https://engage.vic.gov.au/download/document/17516
"In the medium-term, gas providers will begin offering blended gas products. Gas blending
helps to reduce the emissions associated with gas use by blending biomethane, renewable
DME and hydrogen into gas tanks and pipeline systems as part of a long-term effort to reduce
the greenhouse gas (GHG) emission intensity of producing and consuming gas."
So the oil and gas industry is pushing biomethane and hydrogen as the solution to replace methane ("natural") gas.
Most household appliances (ovens, stovetops, hot water systems, heaters, etc) aren't compatible with hydrogen. Pipes will need to be retrofitted too.
Or they can be replaced with electric appliances, which can be powered from the grid by renewables and battery storage.
Either way, it's a big retrofit.
FWIW, green hydrogen (as opposed to grey hydrogen from methane, or brown hydrogen from coal) does have its uses in some applications. But it's not needed for home appliances.
And, going back to the original article, grey hydrogen for buses is not the best way forward for decarbonising transport.