_hypx

24 ms·

151.
by _hypx 3y ago
Please don't trust chatGPT for this. It is likely off by a factor of 10: http://reasonrail.blogspot.com/2015/09/a-cost-to-benefit-ana... It looks like 22-66 kWh/mile, depending on size of train.
152.
by _hypx 3y ago
You need something like 500 tons of batteries, even with superior efficiency numbers taken into account, to match the energy of 5,000 gallons of fuel. It is actually significant if people did the math correctly.
153.
by _hypx 3y ago
You do not need to electrify every meter of track. Trains have enough momentum that you can coast for fairly significant distances. The idea that you need an entire fleet of battery trains just for those short sections beggars belief.
154.
by _hypx 3y ago
BEMUs make zero sense. Just electrify the full route. You eliminate all battery related costs by doing this, nearly guaranteeing it will be cheaper in the long-run. I get the feeling that Germany is overran with "consultants" who
155.
by _hypx 3y ago
This is a very outdated argument. Electrolyzers cost reduce as production capacity expands. All signs suggest that this quickly become a minor source of cost, in the same way PV panels went the same process.
156.
by _hypx 3y ago
CNG vehicles are very common. There are millions of them. It's just the case that in the US, gasoline has been cheap enough to kill off any demand for them. But the US is not the world.
157.
by _hypx 3y ago
Hydrogen is needed for routes with no electrification infrastructure. Think long journeys across the empty parts of the US. There really isn't any alternative to that.
158.
by _hypx 3y ago
The problem is that the cost of batteries pretty quickly undermine the cost savings of not fully electrifying the rail. If it is just a few miles, it makes no sense to have a fleet of battery trains for those short trips.
159.
by _hypx 3y ago
There is no justification for BEMUs in this case because you can simply use direct electrification. The rails are already electrified except for short sections. It's actually a pretty rare scenario to ever need battery powered trains.
160.
by _hypx 3y ago
You liquefy H₂ for the density advantage, not for storage. You actually want to store hydrogen as a gas since it won't boil off.
161.
by _hypx 3y ago
You can liquefy hydrogen on the spot. You don't need to move LH₂ around. If that does become necessary, the solution is improved insulation. Modern materials can reduce boil-off to that of LNG's. In fact, LNG was once seen as impo
162.
by _hypx 3y ago
It is two separate mass transit agencies buying these trains. It doesn't even make sense you can just directly electrify rail instead of using batteries. This is just another greenwashing announcement. Hydrogen trains actually makes se
163.
by _hypx 3y ago
It seems pretty similar to BSCCO: https://en.wikipedia.org/wiki/Bismuth_strontium_calcium_copp...
164.
by _hypx 3y ago
Boiloff is not that big of a deal if you are using the fuel right away. It is the same story as with LNG.
165.
by _hypx 3y ago
There's no such thing as a perfect solution. The problems people keep on bringing up are minor and do not qualify as serious problems.
166.
by _hypx 3y ago
A lot of that is just anti-nuclear propaganda. Nuclear in France does not have major problems.
167.
by _hypx 3y ago
You'd likely send via pipelines or tanker trucks instead.
168.
by _hypx 3y ago
The best density is 33.3 kWh/kg. That's simple physics.
169.
by _hypx 3y ago
You pick one reactor design and make dozens of them. That will be much cheaper than building a bespoke reactor type every time.
170.
by _hypx 3y ago
That's what I said. It's the cost of the powerplant that drives nuclear's cost. But you can reduce that dramatically via mass production of power plants. It will be a cheap source of electricity if done right. And we don&#x27
171.
by _hypx 3y ago
Maybe. The thing about nuclear reactors is that the fuel cost is nearly zero on account of how little of it you need. Even with reprocessing, it is still <$0.01/kWh. So nearly all cost with nuclear is upfront. Mass production of nuc
172.
by _hypx 3y ago
Even then, that's not too bad. In California, electricity is closer to 30-40 cents per kWh. They're nowhere near hitting anything that could be called "high cost."
173.
by _hypx 3y ago
Your own math points out that this is a cost effective technology. 4 cents per kWh is quite cheap electricity.
174.
by _hypx 3y ago
You don't understand the thermodynamics of the situation. Fuel cells/electrolyzers are electrochemical systems with theoretically the same efficiency as batteries. If the alternative is just battery, then both have the same fundam
175.
by _hypx 3y ago
The corn lobby are huge advocates for cellulosic ethanol because it means corn stover could also be made into ethanol.
176.
by _hypx 3y ago
Airplanes are not cars. Weight actually matters, even for short trips. There are not an “ever-increasing” number of routes that can be powered by batteries. You can’t even legally send passengers using batteries, because you can’t even get
177.
by _hypx 3y ago
This is not the true Scotsman fallacy. Biofuels are an environmental disaster, full stop. Anyone who promotes biofuels is aggressively undermining environmental policy.
178.
by _hypx 3y ago
Government subsidized corn ethanol is an environmental disaster. If you hear it being brought up, you automatically assume the person is either confused or working for the corn lobby. Cellulosic ethanol is an idea brought up as a solution t
179.
by _hypx 3y ago
BTW: Biofuels are ludicrously inefficient. Something like 1% of the solar energy actually ends up being usable at the end of the process. That’s not include all the other inputs like fertilizers or pesticides and the like. It is pretty reso
180.
by _hypx 3y ago
Imagine thinking corn ethanol is even remotely a good idea…

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