Trolly wires generally work out cheaper than batteries if you are running frequent service. Batteries work out better anyway though because they allow you to go around obsticals (roadwork, cars illegally parked in the land...)
> Batteries work out better anyway though because they allow you to go around obsticals (roadwork, cars illegally parked in the land...) The pantographs of trolleybuses are often pretty long, so they can switch to the other lane to avoid obstacles.
Now you have a heater in immediate proximity to hydrogen gas. It’s not impossible, but I think you’re underestimating the complexity of doing that safely.
Hydrogen ignition temperature is 535°C.
Did you never do the science experiment? One small spark...
Split shift is a stupid idea that needs to die. It only works for people who always work '9 to 5'. Work a different shift and you drive. Need to go shopping - just drive. Have a day off - drive to whatever you do. Going to church one sundap - drive. Have a kid who might get sick at school - you better drive everyday.
In cities with working public transport it aligns the schedules to accommodate the ridership. Which sucks a bit in the late evening when headways might become a bit long. The absolutely largest peak is in the morning and then a smaller one in the afternoon. So you might have a baseline like every 10 or 15 mins and then in rush hour it is every 3 or 5 mins.
again. Stupid. Complete nonescense that comes from people who drive themselves and think of transit as for 'lesser people'.
humans have places to be. They shouldn't wait for transit. and they mostly won't.
From the article, "A second obvious theme is the prevalence of hydrogen buses in industrial regions and cities that bought into the hydrogen for energy narrative that’s falling apart now. Cologne, Aberdeen, Bolzano, Groningen/Drenthe, and Wuppertal are all trying to be hydrogen valleys, centers of the hydrogen economy’s industry. That’s going badly because it was always a bad idea, devoid of thermodynamic and economi…
I fail to understand how using elemental hydrogen for storing energy has ever sounded like a good idea for anyone. What sounds like a good idea is using fuel cells instead of ICEs, but using hydrocarbons as fuel, not dihydrogen (also solid carbon is a possible fuel). The use of hydrocarbons can be carbon-neutral and sustainable, by making them from carbon dioxide and water. There have been various experiments with fu…
Hydrogen isn't chosen because it's the optimal technical solution (or even a solution at all). It's purpose is to prevent the transition to BEV technology (as a proposed alternative) and thereby protect the businesses making ICEs. It therefore can serve its purpose even if zero Hydrogen vehicles are made.
Of course this was all for the past 30 years. Since everyone can see with their eyes that BEVs work, Hydrogen's job is over.
https://www.sciencedirect.com/topics/engineering/fuel-cell-e... I believe all Hydrogen vehicles are using proton exchange membranes still, which have roughly 40-50% efficiency. And that's before you take into account that even the most cutting edge hydrogen refining processes are around 70% efficient. So 1kWh of energy input (electricity) will net you 3X the motive power when used directly in a BEV than first being c…
I don't think any hydrogen vehicle in actual use has a fuel cell (and if there's any, it's an incredibly rare exception). They are all internal combustion engines.
Proton exchange membranes are very unreliable and expensive. They are also not power-dense, one that powers a bus will be very large.
Still, their point was directionally correct. London has 1397 electric buses and Moscow has over 2300. https://en.m.wikipedia.org/wiki/Low_emission_buses_in_London https://en.m.wikipedia.org/wiki/Electric_buses_in_Moscow
Nobody doubts EVs are more popular now. You should see the numbers for ICE buses too. The discussion is about the future.
Do you expect any problem to appear for batteries at the next century or so? What king of change do you expect on the future for it to not repeat the lessons we learned at the present?
Fossil fuels are on the way out because we do expect problems. Do you have something similar for EVs?
Are those new in Brno? Can't remember them from the last time I was there, but sure sounds interesting
That started showing up maybe ~5 years ago ? Googling a bit I found this article about the first series produced parcial trolley busses (eq. battery equiped) being delivered in 2018: https://www.bmhd.cz/aktuality/aktualita.php?1481 Since then it certainly expanded a lot & there are now regular lines that have the trolleybus go part of the line under its own power, like the recently introduced line to Soběšice: https:…
Do the poles fall off the wires a lot? Our trolley buses in Seattle have a bit of a problem with that. According to the folks I know in San Francisco, theirs do too. They're great otherwise though. Seattle's newer trolley buses can operate off the wire for about 3 miles/5 kilometers (on a LiFePO4 battery) which helps a bit.
If people followed that reasoning, there would be few EVs now because EVs had been tried for decades without success; so were airplanes and AI. If people quit as easily as you say hydrogen car manufacturers should, we wouldn't have much of anything.
Yes - but Hydrogen vehicles have not proven to match or even beat EV's in a lot of key metrics that matter. The biggest one is efficiency. 40% efficient is one figure I saw, versus 80% for EV's. Yes, you can refill quicker, but time to "refuel" EV's is dropping precipitously as well, and it's just all around safer than tanking around highly combustible liquid gas.
It's not really fair to compare the efficiency numbers directly that way. The efficiency for hydrogen is measured from the hydrogen fuel directly, but the efficiency of the EV is measured from the wall. In reality, generating electricity is about 40% efficient at best. Yes, there's also an efficiency cost to refining the hydrogen, but if we compare apples to apples and take a ton of LNG and use it to power an EV versus a hydrogen car, I doubt the EV is going to get more milage.
either release to the atmosphere or inject into an oil well to increase well production.
So H2 fueled vehicles are just indirectly methane fueled, and not carbon-neutral.
Why not electrolyse water? It's not efficient, but if you use solar energy who cares? Set up a plant near the ocean and just let it run. All the inputs are essentially free.