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What is the appeal of a hydrogen car vs an eletric car? The range appears to be similar, but being able to charge at home is so much more convenient.

timthorn 5y ago
Hydrogen cars usually are electric cars. The main advantage to the owner is being able to fill the tank in minutes, and to society as a whole is being able to manage the H2 generation process to align with supply and demand on the grid.
- cbolton 5y ago
  If we're going to store energy by generating H2, is it more efficient to consume it in small cars rather than in big plants that convert it back to electrical power on demand?
  - Cthulhu_ 5y ago
    I don't think the previous commenter meant converting it back; just that if there is an excess of power, e.g. on a sunny and windy day, that can be captured into H2 which is much easier to store than electricity. It wouldn't be converted back to electricity for the grid.
    - deleted 5y ago
      [deleted]
    - cbolton 5y ago
      That's also what I understood, but I'm asking if that's really an argument in favor of H2 vehicles: with electrical vehicles we can also store excess power as H2. Of course we then need to burn it in power plants to convert back to electricity. But which is more efficient? Electricity -> H2 -> electricity -> electrical motor with 80% efficiency vs Electricity -> H2 -> hydrogen motor with 30% efficiency My guess is that "H2 -> electricity" is a bit more efficient than "H2 -> hydrogen motor". So using H2 as excess power storage for hydrogen engines is only marginally better than doing the same for electrical engines. And that's for excess power storage. For "normal" production/consumption the electrical engine is way more efficient.
- _ph_ 5y ago
  Hydrogen production is not well suited to be run depending on the power supply in the grid due to the high prices of the production facilities. If you keep electric cars plugged in, they are far better suited to absorb high supply situations at a much higher efficiency.
bildung 5y ago
Most people can't charge at home (because most people live in multi-story houses in a bigger cities and don't have a garage to charge in), so refueling in 2min at a gas station still has appeal.
- dagw 5y ago
  I personally think we'll see charging poles next to most public parking spaces before we see a sufficiently built out network of H2 'gas stations'.
  - bildung 5y ago
    I think this underestimates the massive infrastructure investments those charging poles would need to work. I live in a medium density European town (about 1000 inhabitants/km2, think 4-5 story buildings on average). In residential areas the whole street is lined with parked cars on both sides. To charge these, one would need something like 1MW charging per every 4 cars, which means every 20m of the road, on both sides. So 1km of inner city street would have new electricity demands of about 100MW for fast charging. Even overnight charging at say 10MW per km of road would mean the complete energy infrastructure of the complete town would have to be changed. Edit: Inserted a line break before the last sentence because apparantly almost every replier overread that one :)
    - pedrocr 5y ago
      > To charge these, one would need something like 1MW charging per every 4 cars This is massively overestimated. 250kW per car is great for fast charging on road trips but for overnight charging it would be enough to charge a car 30+ times in a single night. 3 to 7kW is more than enough. The grid for that is already there and the chargers can even coordinate to not exceed maximum power if everyone plugs in at the same time and draws the maximum. Almost no infrastructure in the town will need to be changed, the existing grid that supplies all the houses will be enough. After all those cars are owned by people that have electricity at home and are practically not using it while they sleep.
    - deleted 5y ago
EwanToo 5y ago
If your home has the appropriate electric supply, then yes, but there's lots of places in the world with poor electricity distribution. The future of transportation seems likely to be a mix of electric, hydrogen, and diesel, depending on the use case for a long time to come.
- prennert 5y ago
  I don't know if there is data to support this, but k have heard hydrogen proponents say that even in London it would be difficult to charge all cars, because the grid could not handle it. So fully electric cars for everybody might not be practical in high density environments.
dagw 5y ago
What is the appeal of a hydrogen car vs an eletric car? Fast 'charging' seems to be the big one. Also for larger engines (like trucks) you should get lower total weight compared to batteries.
- cowmix 5y ago
  I'm begging to doubt this. Right now all hydrogen car are about 15% heavier than their BEV equivalents yet are SLOWER and make worse use of available internal space. When the 4860 cells are used in the structural battery pack, I recken electric semis will have a good power to weight ratio too.
- bsdetector 5y ago
  Often overlooked is when you turn a hydrogen car off, it's off. Come back days or even months later and it should be exactly as you left it. On the other hand a Tesla Model 3 requires a lot of energy to stay warm in the winter - some reports from the dead of winter of it taking 2000 watts just to stay warm. Under extreme conditions you can't leave it unplugged for a week or possibly even a weekend without concern over the battery charge and health. There's better ways to insulate the battery of course, but there's always going to be some tradeoffs to maintain a safe battery temperature at rest and in use.
  - kwhitefoot 5y ago
    > a Tesla Model 3 requires a lot of energy to stay warm in the winter - some reports from the dead of winter of it taking 2000 watts just to stay warm. Under extreme conditions you can't leave it unplugged for a week or possibly even a weekend without concern over the battery charge and health. If that were the case there would be a lot of dead Teslas here in Norway. And even more dead Nissan Leafs which do not have active battery temperature management. I often leave my Model S disconnected over the weekend or longer in -15C in the winter without any noticeable effect on the battery health. It has an effect on range of course because as you say the car does prevent the battery getting too cold. Perhaps I'll try to measure how much energy is required next winter. Here is a first hand anecdote about using a Model S in the Arctic: https://electrek.co/2020/02/11/tesla-model-3-arctic-circle-winter/ https://electrek.co/2020/02/11/tesla-model-3-arctic-circle-w...
teddyh 5y ago
I think it’s precisely that; with electric, there’s no special product to sell you. With hydrogen, or ethanol, the old oil and gas companies can more easily pivot into simply selling another chemical product. With electric cars, the oil and gas companies are like cable TV in the age of the internet; their days are numbered, and they fear it like nothing else. (Also, governments have nothing to levy special taxes on if cars run on your wall plug.) Of course, this is all conspiracy theories and speculation. I have nothing to back this up.
- mustafa_pasi 5y ago
  Asian countries like Japan, Korea and China are the ones who are still pushing hydrogen tech. None of these are big oil producing nations so the conspiracy theory does not make sense.
  - whatever1 5y ago
    Plus the folks here probably forget what poverty looks like. In areas with no infrastructure the only way of getting energy is to literally carry it home for your stove or motorcycle. Gas is ideal for these cases. Hydrogen cylinders maybe? Batteries are definitely a no go to transport energy.
    - bryanlarsen 5y ago
      Those cars have 10,000 PSI tanks, and Hydrogen is notorious for leaking through everything. It's not an option for places with no infrastructure. Trickle charging a battery with a small solar panel is what no-infrastructure places are moving towards for charging phones and other electronics. That's not enough energy for cooking or transportation, yet, but I can see it moving towards that. Another option is synthetic fuel. Currently horribly expensive because it is energy intensive and still experimental, it may become viable if solar energy prices continue to drop. It's much less efficient than an EV, but it works with existing gas/diesel/kerosene infrastructure.
      - 5y ago
jdblair 5y ago
It depends on how you define convenient. Hydrogen can be refilled quickly, in minutes, like a conventional liquid fueled car. If there were a network of hydrogen filling stations then driving, especially long distances, would be similar to driving a liquid fueled car.
- Cthulhu_ 5y ago
  More like an electric car, if it's a hydrogen fuel cell car (I'm not sure if all hydrogen cars are that or if there's another variant that combusts the hydrogen)
  - jdblair 5y ago
    Drives like an electric, refuels like a liquid fuel car (it uses a compressor, not electric charge).
    - bryanlarsen 5y ago
      If by "electric" you mean "Prius", you're right. Tesla's and similar cars have great acceleration because they support massive currents at high voltages. They need this to support fast charging, the incremental cost of adding a high torque motor is small. Hydrogen cars have tiny batteries that don't need to support fast charging. Like a Prius.
      - hwillis 5y ago
        > Hydrogen cars have tiny batteries that don't need to support fast charging. Because that's what they think consumers want, not because of technological limitations. Size is not a requirement for high power batteries. The Porsche 918 has a 6.8 kWh battery that can do 210 kW. That's ~31 kW per kWh, compared to a top-end Model S at ~6 kW/kWh.
        bryanlarsen 5y ago
        Yes, a $800K Hydrogen car would probably have a small but high power battery. But Nexo's and Mirai's don't.
Retric 5y ago
Hydrogen is likely a much better fit for semi trucks, aircraft, boats, and remote rail lines than electric cars. The advantage is twofold, first you can produce and then cheaply store it for weeks and it very quickly refills a car. However the downsides and required infrastructure is massive. Overall it’s simply a poor fit vs modern EV’s but just close enough to viable to get significant investments.
rad_gruchalski 5y ago
Being able to fill up the tank in 2 minutes is the value proposition. When driving a lot or long distances, it matters. Also, not everybody has the possibility to charge at home.
- bdamm 5y ago
  It isn’t that much of a value proposition. Modern EVs do fast charging pretty well. Given that it takes on the order of 10 minutes to pull off a freeway, navigate a traffic light or two, select a pump, pay, use the restroom, grab a snack from the store, and then navigate another intersection to get back on the freeway, adding 5 more minutes to that time to make it a fast charging stop is not really a big deal.
  - dagw 5y ago
    Can modern EVs really fast charge in only 8-10 minutes? I thought we where still talking on the order of 30+ minutes.
    - bryanlarsen 5y ago
      A Tesla with under half a charge charges at a rate of 1000km of range per hour at a Supercharger. So 10 minutes of charging is definitely not a full charge but it is often a useful charge.
    - labcomputer 5y ago
      Put in your favorite road trip, vehicle and any advanced settings you'd like to adjust: https://abetterrouteplanner.com https://abetterrouteplanner.com (No affiliation, just a happy user) Taking a Tesla Model 3 for example, I typically get a 15-20 minute stop every 2-3 hours (standard or long range trim).
  - rad_gruchalski 5y ago
    Right. Assuming that: there is a fast charger available, there is no queue, the charger is not broken. When I drive from Aachen to Berlin, if I have to stop, I stop at the pump, pay - takes 5 minutes, use the bathroom maybe, get in the car and leave. When I arrive in Berlin, I don’t have to look for a parking space where there is a charger, I just park wherever it is legal to park. I leave the meeting, get in the car, stop at the pump if it needs to be and off I go. Roundtrip takes 16 hours. I can do 1000km+ on 65 litres of diesel when driving reasonably or 750km when driving flat out where there is no speed limit. I can use aircon, indicators, satnav, charge stuff in the car and when the gas runs out, I am not forced to have a snack... how often can one snack. There was a test done in Germany. Driving from Hamburg to Munich. Instead of 8 hours, it took over 11. Either a queue at the charger, or you have to adapt the route to get to the charger, or the app says fast charge available but no fast charge was available, or the charger is broken... Sorry, I don’t believe in electric cars but I hold my fingers crossed for h2. Fortunately the hydrogen port built in Antwerpen gives some hope. It’s quite funny looking at all these people in their expensive Taycans on the Autobahn. Either limping 110kph or standing on the hard shoulder with hazards on waiting for adac to turn up.
trutannus 5y ago
Same question from me also. Also, hydrogen is highly explosive, so how can that be safely used in cars without detonating a la Hindenburg whenever there's a collision?
- gnull 5y ago
  It is explosive only when mixed with enough oxygen, much like gasoline or propane. Hindenburg did not explode, it burned (quite fast, I should add). As I understand, If you make a hole in hydrogen tank and set it on fire, it will just burn (don't try to do this at home).
  - trutannus 5y ago
    > If you make a hole in hydrogen tank and set it on fire Right, the issue is though that in a collision you won't always just have a nice small controlled hole and burn. I've worked around Hydrogen before, and storage was always a tricky issue. I remember the regulations stating something like needing to store the tank with either Argon or Nitrogen beside it. Not really something I'd want in the back, or any part for that matter, of my car.
    - gnull 5y ago
      Sorry, my bad, I misunderstood what you meant.
- _gtly 5y ago
  The danger of using hydrogen gas in a vehicle may be on the same order as compressed natural gas (CNG) which is used for e.g.: some busses. Hydrogen is stored under very high pressure in tanks, which if ruptured in an accident can cause a physical explosion. A study on CNG in busses says: "One can therefore conclude that CNG buses are more prone to fire fatality risk by 2.5 times that of diesel buses, with the bus passengers being more at risk by over two orders of magnitude." source: https://pubmed.ncbi.nlm.nih.gov/15876211/#:~:text=One%20can%20therefore%20conclude%20that,)%20fatalities%2Fbus%20per%20year https://pubmed.ncbi.nlm.nih.gov/15876211/#:~:text=One%20can%....
roel_v 5y ago
I live in a city center, no driveway. My neighbour with an electric i3 runs a charging cord across the sidewalk, I'm not going to do that, ever. I'd much prefer a hydrogen car I can fill up someplace else over requiring plugging in my car every day.
GuB-42 5y ago
Hydrogen has a great energy density, that's why it is used in rockets. It may have similar range as battery electric cars but it can scale better. It can be refueled in minutes, like gas cars. And the economy is based on using "waste" renewable energy. The problem is that solar panels and wind turbines don't produce energy when we need it the most (see: duck curve). The idea is to store that energy as hydrogen and use it in vehicles. For commuters with a garage and a charging spot, batteries are more convenient but I think big trucks can benefit more from hydrogen. Now the big question is, can we modify these hydrogen trucks to "roll steam" at these pesky Teslas.
- thehappypm 5y ago
  Hydrogen isn't used in rockets much. It's actually not energy dense enough compared to more exotic fuels.
  - GuB-42 5y ago
    You are right, but considering that many people think it is too dangerous to put hydrogen tanks in cars, I wonder what they are going to say about "exotic rocket fuels" :) For reference, here is a quote from the Ignition! book about Chlorine trifluoride. It is an oxidizer, not a fuel but you get the idea. > It is, of course, extremely toxic, but that’s the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.
- bkor 5y ago
  > And the economy is based on using "waste" renewable energy. The problem is that solar panels and wind turbines don't produce energy when we need it the most (see: duck curve). The idea is to store that energy as hydrogen and use it in vehicles. I've seem this statement loads of times before. But actually, Hydrogen production is not economical if you do not produce it continuously. Meaning, it does not make economical sense to only use excess energy capacity. Further, Hydrogen for cars is highly inefficient if you take all of the steps into account. For the foreseeable future the common expectation is that Hydrogen is produced from fossil fuels (e.g. read forecasts from analysts or companies such as Shell). This while at the same time they pretend it'll make this more green. Hydrogen is already produced in huge quantities btw, but it's somewhat hidden as it's used by industry. Meaning, most people wouldn't even notice it. Unlike e.g. seeing a new hydrogen gas station.
asciimov 5y ago
For me the biggest appeal is you could convert a petrol powered car to run off of hydrogen. While they are not as efficient as fuel cell, running a regular engine off of hydrogen would allow us to create demand for fueling stations faster than waiting on fuel cell cars to gradually enter the market.

timthorn 5y ago

Hydrogen cars usually are electric cars. The main advantage to the owner is being able to fill the tank in minutes, and to society as a whole is being able to manage the H2 generation process to align with supply and demand on the grid.

cbolton 5y ago
If we're going to store energy by generating H2, is it more efficient to consume it in small cars rather than in big plants that convert it back to electrical power on demand?
- Cthulhu_ 5y ago
  I don't think the previous commenter meant converting it back; just that if there is an excess of power, e.g. on a sunny and windy day, that can be captured into H2 which is much easier to store than electricity. It wouldn't be converted back to electricity for the grid.
  - deleted 5y ago
    [deleted]
  - cbolton 5y ago
    That's also what I understood, but I'm asking if that's really an argument in favor of H2 vehicles: with electrical vehicles we can also store excess power as H2. Of course we then need to burn it in power plants to convert back to electricity. But which is more efficient? Electricity -> H2 -> electricity -> electrical motor with 80% efficiency vs Electricity -> H2 -> hydrogen motor with 30% efficiency My guess is that "H2 -> electricity" is a bit more efficient than "H2 -> hydrogen motor". So using H2 as excess power storage for hydrogen engines is only marginally better than doing the same for electrical engines. And that's for excess power storage. For "normal" production/consumption the electrical engine is way more efficient.
_ph_ 5y ago
Hydrogen production is not well suited to be run depending on the power supply in the grid due to the high prices of the production facilities. If you keep electric cars plugged in, they are far better suited to absorb high supply situations at a much higher efficiency.

bildung 5y ago

Most people can't charge at home (because most people live in multi-story houses in a bigger cities and don't have a garage to charge in), so refueling in 2min at a gas station still has appeal.

dagw 5y ago
I personally think we'll see charging poles next to most public parking spaces before we see a sufficiently built out network of H2 'gas stations'.
- bildung 5y ago
  I think this underestimates the massive infrastructure investments those charging poles would need to work. I live in a medium density European town (about 1000 inhabitants/km2, think 4-5 story buildings on average). In residential areas the whole street is lined with parked cars on both sides. To charge these, one would need something like 1MW charging per every 4 cars, which means every 20m of the road, on both sides. So 1km of inner city street would have new electricity demands of about 100MW for fast charging. Even overnight charging at say 10MW per km of road would mean the complete energy infrastructure of the complete town would have to be changed. Edit: Inserted a line break before the last sentence because apparantly almost every replier overread that one :)
  - pedrocr 5y ago
    > To charge these, one would need something like 1MW charging per every 4 cars This is massively overestimated. 250kW per car is great for fast charging on road trips but for overnight charging it would be enough to charge a car 30+ times in a single night. 3 to 7kW is more than enough. The grid for that is already there and the chargers can even coordinate to not exceed maximum power if everyone plugs in at the same time and draws the maximum. Almost no infrastructure in the town will need to be changed, the existing grid that supplies all the houses will be enough. After all those cars are owned by people that have electricity at home and are practically not using it while they sleep.
  - deleted 5y ago

EwanToo 5y ago

If your home has the appropriate electric supply, then yes, but there's lots of places in the world with poor electricity distribution. The future of transportation seems likely to be a mix of electric, hydrogen, and diesel, depending on the use case for a long time to come.

prennert 5y ago
I don't know if there is data to support this, but k have heard hydrogen proponents say that even in London it would be difficult to charge all cars, because the grid could not handle it. So fully electric cars for everybody might not be practical in high density environments.

dagw 5y ago

What is the appeal of a hydrogen car vs an eletric car? Fast 'charging' seems to be the big one. Also for larger engines (like trucks) you should get lower total weight compared to batteries.

cowmix 5y ago
I'm begging to doubt this. Right now all hydrogen car are about 15% heavier than their BEV equivalents yet are SLOWER and make worse use of available internal space. When the 4860 cells are used in the structural battery pack, I recken electric semis will have a good power to weight ratio too.
bsdetector 5y ago
Often overlooked is when you turn a hydrogen car off, it's off. Come back days or even months later and it should be exactly as you left it. On the other hand a Tesla Model 3 requires a lot of energy to stay warm in the winter - some reports from the dead of winter of it taking 2000 watts just to stay warm. Under extreme conditions you can't leave it unplugged for a week or possibly even a weekend without concern over the battery charge and health. There's better ways to insulate the battery of course, but there's always going to be some tradeoffs to maintain a safe battery temperature at rest and in use.
- kwhitefoot 5y ago
  > a Tesla Model 3 requires a lot of energy to stay warm in the winter - some reports from the dead of winter of it taking 2000 watts just to stay warm. Under extreme conditions you can't leave it unplugged for a week or possibly even a weekend without concern over the battery charge and health. If that were the case there would be a lot of dead Teslas here in Norway. And even more dead Nissan Leafs which do not have active battery temperature management. I often leave my Model S disconnected over the weekend or longer in -15C in the winter without any noticeable effect on the battery health. It has an effect on range of course because as you say the car does prevent the battery getting too cold. Perhaps I'll try to measure how much energy is required next winter. Here is a first hand anecdote about using a Model S in the Arctic: https://electrek.co/2020/02/11/tesla-model-3-arctic-circle-winter/ https://electrek.co/2020/02/11/tesla-model-3-arctic-circle-w...

teddyh 5y ago

I think it’s precisely that; with electric, there’s no special product to sell you. With hydrogen, or ethanol, the old oil and gas companies can more easily pivot into simply selling another chemical product. With electric cars, the oil and gas companies are like cable TV in the age of the internet; their days are numbered, and they fear it like nothing else. (Also, governments have nothing to levy special taxes on if cars run on your wall plug.) Of course, this is all conspiracy theories and speculation. I have nothing to back this up.

mustafa_pasi 5y ago
Asian countries like Japan, Korea and China are the ones who are still pushing hydrogen tech. None of these are big oil producing nations so the conspiracy theory does not make sense.
- whatever1 5y ago
  Plus the folks here probably forget what poverty looks like. In areas with no infrastructure the only way of getting energy is to literally carry it home for your stove or motorcycle. Gas is ideal for these cases. Hydrogen cylinders maybe? Batteries are definitely a no go to transport energy.
  - bryanlarsen 5y ago
    Those cars have 10,000 PSI tanks, and Hydrogen is notorious for leaking through everything. It's not an option for places with no infrastructure. Trickle charging a battery with a small solar panel is what no-infrastructure places are moving towards for charging phones and other electronics. That's not enough energy for cooking or transportation, yet, but I can see it moving towards that. Another option is synthetic fuel. Currently horribly expensive because it is energy intensive and still experimental, it may become viable if solar energy prices continue to drop. It's much less efficient than an EV, but it works with existing gas/diesel/kerosene infrastructure.
    - 5y ago

jdblair 5y ago

It depends on how you define convenient. Hydrogen can be refilled quickly, in minutes, like a conventional liquid fueled car. If there were a network of hydrogen filling stations then driving, especially long distances, would be similar to driving a liquid fueled car.

Cthulhu_ 5y ago
More like an electric car, if it's a hydrogen fuel cell car (I'm not sure if all hydrogen cars are that or if there's another variant that combusts the hydrogen)
- jdblair 5y ago
  Drives like an electric, refuels like a liquid fuel car (it uses a compressor, not electric charge).
  - bryanlarsen 5y ago
    If by "electric" you mean "Prius", you're right. Tesla's and similar cars have great acceleration because they support massive currents at high voltages. They need this to support fast charging, the incremental cost of adding a high torque motor is small. Hydrogen cars have tiny batteries that don't need to support fast charging. Like a Prius.
    - hwillis 5y ago
      > Hydrogen cars have tiny batteries that don't need to support fast charging. Because that's what they think consumers want, not because of technological limitations. Size is not a requirement for high power batteries. The Porsche 918 has a 6.8 kWh battery that can do 210 kW. That's ~31 kW per kWh, compared to a top-end Model S at ~6 kW/kWh.
      - bryanlarsen 5y ago
        Yes, a $800K Hydrogen car would probably have a small but high power battery. But Nexo's and Mirai's don't.

Retric 5y ago

Hydrogen is likely a much better fit for semi trucks, aircraft, boats, and remote rail lines than electric cars. The advantage is twofold, first you can produce and then cheaply store it for weeks and it very quickly refills a car. However the downsides and required infrastructure is massive. Overall it’s simply a poor fit vs modern EV’s but just close enough to viable to get significant investments.

rad_gruchalski 5y ago

Being able to fill up the tank in 2 minutes is the value proposition. When driving a lot or long distances, it matters. Also, not everybody has the possibility to charge at home.

bdamm 5y ago
It isn’t that much of a value proposition. Modern EVs do fast charging pretty well. Given that it takes on the order of 10 minutes to pull off a freeway, navigate a traffic light or two, select a pump, pay, use the restroom, grab a snack from the store, and then navigate another intersection to get back on the freeway, adding 5 more minutes to that time to make it a fast charging stop is not really a big deal.
- dagw 5y ago
  Can modern EVs really fast charge in only 8-10 minutes? I thought we where still talking on the order of 30+ minutes.
  - bryanlarsen 5y ago
    A Tesla with under half a charge charges at a rate of 1000km of range per hour at a Supercharger. So 10 minutes of charging is definitely not a full charge but it is often a useful charge.
  - labcomputer 5y ago
    Put in your favorite road trip, vehicle and any advanced settings you'd like to adjust: https://abetterrouteplanner.com https://abetterrouteplanner.com (No affiliation, just a happy user) Taking a Tesla Model 3 for example, I typically get a 15-20 minute stop every 2-3 hours (standard or long range trim).
- rad_gruchalski 5y ago
  Right. Assuming that: there is a fast charger available, there is no queue, the charger is not broken. When I drive from Aachen to Berlin, if I have to stop, I stop at the pump, pay - takes 5 minutes, use the bathroom maybe, get in the car and leave. When I arrive in Berlin, I don’t have to look for a parking space where there is a charger, I just park wherever it is legal to park. I leave the meeting, get in the car, stop at the pump if it needs to be and off I go. Roundtrip takes 16 hours. I can do 1000km+ on 65 litres of diesel when driving reasonably or 750km when driving flat out where there is no speed limit. I can use aircon, indicators, satnav, charge stuff in the car and when the gas runs out, I am not forced to have a snack... how often can one snack. There was a test done in Germany. Driving from Hamburg to Munich. Instead of 8 hours, it took over 11. Either a queue at the charger, or you have to adapt the route to get to the charger, or the app says fast charge available but no fast charge was available, or the charger is broken... Sorry, I don’t believe in electric cars but I hold my fingers crossed for h2. Fortunately the hydrogen port built in Antwerpen gives some hope. It’s quite funny looking at all these people in their expensive Taycans on the Autobahn. Either limping 110kph or standing on the hard shoulder with hazards on waiting for adac to turn up.

trutannus 5y ago

Same question from me also. Also, hydrogen is highly explosive, so how can that be safely used in cars without detonating a la Hindenburg whenever there's a collision?

gnull 5y ago
It is explosive only when mixed with enough oxygen, much like gasoline or propane. Hindenburg did not explode, it burned (quite fast, I should add). As I understand, If you make a hole in hydrogen tank and set it on fire, it will just burn (don't try to do this at home).
- trutannus 5y ago
  > If you make a hole in hydrogen tank and set it on fire Right, the issue is though that in a collision you won't always just have a nice small controlled hole and burn. I've worked around Hydrogen before, and storage was always a tricky issue. I remember the regulations stating something like needing to store the tank with either Argon or Nitrogen beside it. Not really something I'd want in the back, or any part for that matter, of my car.
  - gnull 5y ago
    Sorry, my bad, I misunderstood what you meant.
_gtly 5y ago
The danger of using hydrogen gas in a vehicle may be on the same order as compressed natural gas (CNG) which is used for e.g.: some busses. Hydrogen is stored under very high pressure in tanks, which if ruptured in an accident can cause a physical explosion. A study on CNG in busses says: "One can therefore conclude that CNG buses are more prone to fire fatality risk by 2.5 times that of diesel buses, with the bus passengers being more at risk by over two orders of magnitude." source: https://pubmed.ncbi.nlm.nih.gov/15876211/#:~:text=One%20can%20therefore%20conclude%20that,)%20fatalities%2Fbus%20per%20year https://pubmed.ncbi.nlm.nih.gov/15876211/#:~:text=One%20can%....

roel_v 5y ago

I live in a city center, no driveway. My neighbour with an electric i3 runs a charging cord across the sidewalk, I'm not going to do that, ever. I'd much prefer a hydrogen car I can fill up someplace else over requiring plugging in my car every day.

GuB-42 5y ago

Hydrogen has a great energy density, that's why it is used in rockets. It may have similar range as battery electric cars but it can scale better. It can be refueled in minutes, like gas cars. And the economy is based on using "waste" renewable energy. The problem is that solar panels and wind turbines don't produce energy when we need it the most (see: duck curve). The idea is to store that energy as hydrogen and use it in vehicles. For commuters with a garage and a charging spot, batteries are more convenient but I think big trucks can benefit more from hydrogen. Now the big question is, can we modify these hydrogen trucks to "roll steam" at these pesky Teslas.

thehappypm 5y ago
Hydrogen isn't used in rockets much. It's actually not energy dense enough compared to more exotic fuels.
- GuB-42 5y ago
  You are right, but considering that many people think it is too dangerous to put hydrogen tanks in cars, I wonder what they are going to say about "exotic rocket fuels" :) For reference, here is a quote from the Ignition! book about Chlorine trifluoride. It is an oxidizer, not a fuel but you get the idea. > It is, of course, extremely toxic, but that’s the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water-with which it reacts explosively. It can be kept in some of the ordinary structural metals-steel, copper, aluminium, etc.-because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminium keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes.
bkor 5y ago
> And the economy is based on using "waste" renewable energy. The problem is that solar panels and wind turbines don't produce energy when we need it the most (see: duck curve). The idea is to store that energy as hydrogen and use it in vehicles. I've seem this statement loads of times before. But actually, Hydrogen production is not economical if you do not produce it continuously. Meaning, it does not make economical sense to only use excess energy capacity. Further, Hydrogen for cars is highly inefficient if you take all of the steps into account. For the foreseeable future the common expectation is that Hydrogen is produced from fossil fuels (e.g. read forecasts from analysts or companies such as Shell). This while at the same time they pretend it'll make this more green. Hydrogen is already produced in huge quantities btw, but it's somewhat hidden as it's used by industry. Meaning, most people wouldn't even notice it. Unlike e.g. seeing a new hydrogen gas station.

asciimov 5y ago

For me the biggest appeal is you could convert a petrol powered car to run off of hydrogen. While they are not as efficient as fuel cell, running a regular engine off of hydrogen would allow us to create demand for fueling stations faster than waiting on fuel cell cars to gradually enter the market.