Battery augmented trains: Given normal EV use examples, Tesla et al, and Tesla Semi a charging time of 10% of usage time is relatively normal. Eg charging for 20 minutes and discharging for 3 hours, or in Tesla Semi’s case might be more like an hour for 8-10 hours operation but trains have lower drag (and less penalty for weight) than cars or trucks so will go further for same amount of energy. The idea is therefore that you employ a pantograph multi MW charging system on the train that only needs to operate about 10% of the time,. This may reduce electrification capital and maintenance costs. Another option would be battery engines that can join up or disconnect from trains in motion between charging cycles in sidings.
I work professionally developing Liquid hydrogen fueled transport power technology. It’s very practical for some applications, particularly aircraft and ships that I expect will transition to hydrogen in next 2-3 decades, and possibly trains and agriculture. Using low cost power sources such as grid scale pv in low cost desert regions the price is expected to come down over next 1-2 decades to being competitive or even undercutting fossil fuels (commonly expected/roadmapped to be ~$1.5/kg H2, which translates to about $0.10/kWh useful output power, similar to fossil fuels before taxes). This is likely the only realistic route to fully renewable power for human civilisation—producing in cheapest sunny or windy areas and using at high latitudes/through winters. But LH2 is difficult to transport, transfer and employ at small scales due to lack of economic cryocooling and complexity, insulation and cost scale (r² vs r³) issues with tanks (LH2 and GH2 are very low density) and GH2 is even worse for non-pipeline distribution, so a more convenient dense and long-term easily and cheaply stored energy carrier such as Ammonia or synthetic hydrocarbons made using future cheap hydrogen feedstocks may be a better option. That is especially true for off-road uses.
Agriculture is particularly intractable, cropping farmers in my region frequently run 100+ hours a week using many MW of power during harvest which is a terrible issue for power economics without exceptionally cheap energy storage—liquid fuel is probably the only economic option.
And yes I am well aware of mining electrification, but I am very suspicious of it’s utility given many cases will see it powered by fossil fuel generation. Likely that a lot of it is PR greenwashing rather than effective CO2 reduction.
I work professionally developing Liquid hydrogen fueled transport power technology.
So your job depends on believing the projections about how H2 costs will come down?
It’s very practical for some applications, particularly aircraft and ships that I expect will transition to hydrogen in next 2-3 decades, and possibly trains and agriculture.
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This is likely the only realistic route to fully renewable power for human civilisation—producing in cheapest sunny or windy areas and using at high latitudes/through winters.
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so a more convenient dense and long-term easily and cheaply stored energy carrier such as Ammonia or synthetic hydrocarbons made using future cheap hydrogen feedstocks may be a better option.
It’s possible that direct production of synthetic hydrocarbons will be more effective than going through H2 production. Given that we already have ships that can drive well if you fuel them with gas, it’s possible that all the money invested into trying to get ships to run on hydrogen will be wasted.
“So your job depends on believing the projections about how H2 costs will come down?”
I wouldn’t waste my life on something I didn’t see as likely—I have no shortage of opportunities in a wide variety of greentech fields. Hydrogen is the most efficient fuel storage ‘battery’ with 40-50% round-trip energy storage possible. Other synthetic fuels are less efficient but may be necessary for longer term storage or smaller applications. For shipping and aviation however LH2 is the clear and obvious winner.
Desert pv will likely come down in price to consistent ~$0.01-0.02 in next decade with impact of AI on manufacturing, installation and maintenance costs (a few large pv installations are already contracted in this cost range). And electrolysis and liquefaction tech are on track to yield the stated $1.50/kg (learning curves are magic). That ‘stranded’ desert pv power needs to be delivered to far distant users and hydrogen pipelines or shipping provides most realistic option for doing that.
Capturing carbon for synthetic hydrocarbons is not a trivial issue/cost. And their round trip energy storage efficiencies for synthetics hydrocarbons are worse than for hydrogen. There will still be some applications where they make the most sense. Ammonia might work too, though it also needs hydrogen feedstock and is often lethal when inhaled.
But in general I see a pretty clear path to renewable hydrogen undercutting fossil fuels on cost in the next decade or two, and from there a likely rapid decline in their use - so reasons for optimism about energy part of our civilisational tech stack at least, without breakthroughs in nuclear being needed.
Hydrogen is the most efficient fuel storage ‘battery’ with 40-50% round-trip energy storage possible [...] Desert pv will likely come down in price to consistent ~$0.01-0.02
If energy prices come down so much, the round-trip efficiency is not central.
You need much larger storage tanks in both ships and airplanes if you go for hydrogen than if you use denser fuel.
And electrolysis and liquefaction tech are on track to yield the stated $1.50/kg (learning curves are magic).
If that’s true why are the subventions for its production so high? What sources do you find trustworthy for those costs in an environment where plenty of the players have incentives to make people believe in a certain future?
charging time of 10% of usage time is relatively normal
Charge time partly depends on power available, but is typically set to 1 hour to reduce battery degradation. Discharge time depends on battery size relative to power usage. They’re not directly related.
have stated that they believe cost per kWh can come down to $40/kWh
I understand battery chemistry fairly well, and my view is, they’re lying for strategic reasons.
Battery augmented trains: Given normal EV use examples, Tesla et al, and Tesla Semi a charging time of 10% of usage time is relatively normal. Eg charging for 20 minutes and discharging for 3 hours, or in Tesla Semi’s case might be more like an hour for 8-10 hours operation but trains have lower drag (and less penalty for weight) than cars or trucks so will go further for same amount of energy. The idea is therefore that you employ a pantograph multi MW charging system on the train that only needs to operate about 10% of the time,. This may reduce electrification capital and maintenance costs. Another option would be battery engines that can join up or disconnect from trains in motion between charging cycles in sidings.
CATL (largest battery producer in the world) are innovating heavily on Sodium ion batteries and have stated that they believe cost per kWh can come down to $40/kWh as they scale up manufacture on their second generation. “CATL first-generation sodium-ion cells cost about 77 USD per kWh, and the second generation with volume production can drop to 40 USD per kWh.”
I work professionally developing Liquid hydrogen fueled transport power technology. It’s very practical for some applications, particularly aircraft and ships that I expect will transition to hydrogen in next 2-3 decades, and possibly trains and agriculture. Using low cost power sources such as grid scale pv in low cost desert regions the price is expected to come down over next 1-2 decades to being competitive or even undercutting fossil fuels (commonly expected/roadmapped to be ~$1.5/kg H2, which translates to about $0.10/kWh useful output power, similar to fossil fuels before taxes). This is likely the only realistic route to fully renewable power for human civilisation—producing in cheapest sunny or windy areas and using at high latitudes/through winters. But LH2 is difficult to transport, transfer and employ at small scales due to lack of economic cryocooling and complexity, insulation and cost scale (r² vs r³) issues with tanks (LH2 and GH2 are very low density) and GH2 is even worse for non-pipeline distribution, so a more convenient dense and long-term easily and cheaply stored energy carrier such as Ammonia or synthetic hydrocarbons made using future cheap hydrogen feedstocks may be a better option. That is especially true for off-road uses.
Agriculture is particularly intractable, cropping farmers in my region frequently run 100+ hours a week using many MW of power during harvest which is a terrible issue for power economics without exceptionally cheap energy storage—liquid fuel is probably the only economic option.
And yes I am well aware of mining electrification, but I am very suspicious of it’s utility given many cases will see it powered by fossil fuel generation. Likely that a lot of it is PR greenwashing rather than effective CO2 reduction.
So your job depends on believing the projections about how H2 costs will come down?
It’s possible that direct production of synthetic hydrocarbons will be more effective than going through H2 production. Given that we already have ships that can drive well if you fuel them with gas, it’s possible that all the money invested into trying to get ships to run on hydrogen will be wasted.
“So your job depends on believing the projections about how H2 costs will come down?”
I wouldn’t waste my life on something I didn’t see as likely—I have no shortage of opportunities in a wide variety of greentech fields. Hydrogen is the most efficient fuel storage ‘battery’ with 40-50% round-trip energy storage possible. Other synthetic fuels are less efficient but may be necessary for longer term storage or smaller applications. For shipping and aviation however LH2 is the clear and obvious winner.
Desert pv will likely come down in price to consistent ~$0.01-0.02 in next decade with impact of AI on manufacturing, installation and maintenance costs (a few large pv installations are already contracted in this cost range). And electrolysis and liquefaction tech are on track to yield the stated $1.50/kg (learning curves are magic). That ‘stranded’ desert pv power needs to be delivered to far distant users and hydrogen pipelines or shipping provides most realistic option for doing that.
Capturing carbon for synthetic hydrocarbons is not a trivial issue/cost. And their round trip energy storage efficiencies for synthetics hydrocarbons are worse than for hydrogen. There will still be some applications where they make the most sense. Ammonia might work too, though it also needs hydrogen feedstock and is often lethal when inhaled.
But in general I see a pretty clear path to renewable hydrogen undercutting fossil fuels on cost in the next decade or two, and from there a likely rapid decline in their use - so reasons for optimism about energy part of our civilisational tech stack at least, without breakthroughs in nuclear being needed.
If energy prices come down so much, the round-trip efficiency is not central.
You need much larger storage tanks in both ships and airplanes if you go for hydrogen than if you use denser fuel.
If that’s true why are the subventions for its production so high? What sources do you find trustworthy for those costs in an environment where plenty of the players have incentives to make people believe in a certain future?
Thanks.
Charge time partly depends on power available, but is typically set to 1 hour to reduce battery degradation. Discharge time depends on battery size relative to power usage. They’re not directly related.
I understand battery chemistry fairly well, and my view is, they’re lying for strategic reasons.
see this post for my comments