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.
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.
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.
It's not challenging to make a cheap, small battery that can provide 200 kW. It just happens that it hasn't been prioritized.
A provable example: 1,826 Sony VTC4 18650 cells will push 200 kW continuously. That's only 14 kWh of storage and weighs <100 kg. It's a 28.5"/72 cm square 3"/7.5 cm thick. I could personally build that battery for <10k USD. A full scale automaker should be able to do it for half that.
That would almost triple (136 -> 336) the Mirai's power and put it (2050 kg @curb) in spitting distance of the 550i (390 kW, 2020 kg @curb). The BMW's MSRP starts 27k USD higher.
Of course you would need to change the suspension and geometry completely, make the interior far nicer, and add even more power to be able to actually compete with the 550i, but the point stands. A small, powerful battery is cheap and easy to add to a FCV.
NB that I'm an electrical engineer and have built many batteries before, including from 18650s. First off, it is absolutely not necessary to have so many controllers; cell-level controllers are only used in the cheapest batteries. High-quality batteries will match cells individually and switch them in groups, which reduces the losses from running a bunch of parallel circuitry. This is not really different from simply using larger cells, as long as you can match them sufficiently well.
Cell-level BMS is very cheap as a result, for example this single cell chip that costs 7 cents each: https://lcsc.com/product-detail/PMIC-Battery-Management_HY22...
> Plus the hassle and cost of using bus bars instead of wires.
Only if you're using 18650s; if you are using prismatic cells you just solder or crimp the tabs to the HV supply. If you're using small-format cells, you would typically used stamped sheet current carriers rather than busbars.
> And it means that the battery module output is 3.6V at an insane amperage and needs a massive transformer for a reasonable voltage.
It certainly does not, because batteries are DC and you do not use transformers to convert their voltage. Transformers require you to convert to AC and back, but you can use an inductor ~100x smaller by using one of the many "boost" topologies. The basic idea is that you only need to convert to AC, and you don't need to rectify back to DC. You chop the high-current DC up very finely, then store 1-3 cycles in a very small inductor. If the inductor is sized just right, it will drain out current that is very close to DC.
Naturally though you would really want to operate between the 245 volts of the Mirai's battery or the 650 volts of the Mirai's fuel stack. That would be something between a 68s27p pack and a 180s10p pack. That's far more efficient. You can still have cell-level BMS for every single cell- that IC I linked above is daisy-chainable, meaning it does not need a real 0v ground reference. It's perfectly happy working at whatever voltages on the two ends of the particular cell its connected to. In this case I'd opt for something closer to 68s- the more cells you have in series, the more susceptible your design is to degraded performance over time.
Hydrogen is more energy-dense than gasoline, but it's much more of a pain in the ass. Gasoline is far denser than air but hydrogen is far less dense, so normal injection displaces a ton (30%) of oxygen from the cylinders. You need to use direct injection to get any kind of power out of hydrogen, and a very high-flow fuel pump.
Combustion is also much hotter than normal, so you produce a ton of NOx compounds; that's why there's a huge catalytic converter on the back of the Toyota.
Without the efficiency of a fuel cell there's quite a lot of loss of range. The potential for increased power+lower weight in high performance vehicles could do a lot to combat the halo effect of gasoline... or at least I hope so.
Only if the gas station has enough hydrogen at the right pressure. After a few cars it'll need 45+min to build up pressure again. The gas stations are really expensive due to the problems, plus there are more restrictions on where they can be placed.
Hydrogen for cars is great for companies such as Shell. For the foreseeable future they expect most of the Hydrogen to be created using non-green methods. Even if it's green, you'll need way more green energy (e.g. wind / solar). Way more profit to be had.
Note that due to increase of EVs the safety requirements for garages have been increased (in NL). E.g. more monitoring is needed, automatic link to fire department, plus changes in construction requirements. Construction bit is due to an EV burning for longer. They basically demand thicker concrete walls and so on. This from memory and it's only what I've been reading (interested in safety; I don't work in construction).
But the problem is there will never be an equivalent hydrogen network as there is gasoline network because hydrogen fueling stations are far more expensive to install and maintain. Either the station overhead ends up much higher than gasoline or hydrogen is used much more rarely.
Electric car distance records as of 2018 are 1178km in a Model S and 1001km in a Model 3. https://www.teslarati.com/tesla-model-s-model-3-hypermile-wo...
Model S Plaid+ next year is supposed to have ~50% greater range than the Model S used in that 2018 record. And has a nationwide charging network (and access to other EV charging networks, which themselves are becoming impressive... Lucid Air’s offering is also impressive).
I just don’t see the attraction of hydrogen any more besides niche applications.
The vehicles are much more expensive (Model 3 way cheaper than equivalent range Toyota Mirai), the charging is far less convenient and totally unavailable outside California, they’re slower, and the fuel is vastly more expensive, and they’re fundamentally less energy efficient. Heck, the Model 3 LR actually weighs less and has more range than the Toyota Mirai.
Hydrogen cars are a bonfire of money.
Conventional carmakers insistent on fast fueling capability ought to do plug-in hybrid. Even if you use synthesized fuel for the few trips that go beyond the electric range, the cost per mile (and cost per vehicle) would be way lower than hydrogen and you could use existing gas stations (although we’d need a lot fewer of them), and you still get the logistical benefit of home/work charging for commutes.
You could switch everyone’s car for a plug in hybrid version today and they wouldn’t even know except it’d sound different. We could ban new vehicles without a plug and it wouldn’t ruin anyone’s corner case commute and a lot of people wouldn’t even realize it at first (just like many don’t realize they drive a mild hybrid). This is a far better argument than hydrogen cars’ “liquid fueling like experience! But only in a handful of stations in California at enormous expense...”
https://www.hydrogen.energy.gov/pdfs/progress18/tahi_lohse-b...
Cold weather isn’t a major problem, either, you just will want to get a heat pump option. Electric cars are insanely popular in Norway, and it doesn’t seem to be a significant problem.
Hydrogen itself doesn't. But the fuel cells do. I can imagine there will be problems with the plumbing as well, as hydrogen has a tendency to make materials it comes into contact with brittle.
> If one lives in a cold weather climate, owning a Tesla isn't as advantageous.
Eh, it's fine. Norway is the EV capital of the world. Range is decreased, but it's not really a problem in day-to-day driving. We have an older 30kWh EV, with less than 100km range in winter. It's almost never an issue. Even driving 2 hours to a cabin is fine with a fast-charge that takes less time than buying groceries next to the fast charge station.
In colder climates, it's more common for people to have garages where they can charge at home. There are even colder areas, and remote areas where the range really is a big issue, but then we're talking about areas with very small populations. If all of them continue to drive diesel cars, it'll be a microscopic blip in terms of global CO2 emissions.
0: https://techcrunch.com/2013/07/26/inside-teslas-supercharger...
1: https://www.wardsauto.com/technology/costs-check-growth-fuel...
(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.
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.
Now, do we have cheap appliances that consume hydrogen and produce work/heat ? Not yet.
That isn’t how things work but that’s the logic behind pushing Hydrogen.
Big companies such as Shell are pushing Hydrogen via something called the "EU green deal". This while Shell (and similar) do not expect hydrogen to be produced via green methods for 15+ years. They push the EU to "subsidize" hydrogen (and other things), to basically get loads of money from people in an indirect way.
This was e.g. reported via the journalists at ftm.nl. They're probably unknown to most people here, but loads of their findings resulted in loads of issues for the government (scandals, fraud, etc).
https://www.wsj.com/amp/articles/toyotas-chief-says-electric...
Japan heavily subsidises research into Hydrogen. This over anything else, e.g. electric. Quoting a Japanese car manufacturer is therefore a bit biased. Japan has two different energy grids btw, one runs at 50 Hz, the other at 60 Hz. Japan made some really strange decisions regarding their electric grid. That makes Japan unique, it isn't common to have such problems.
For most countries the additional electric requirements aren't that significant. Though there will need to be some behavioural change (possibly helped by some technology). E.g. don't charge everything immediately at once, but align the supply and demand. Meaning, don't charge everything at once, charge more when there's an over supply (e.g. windy day/hour).
But I still doubt is hydrogen for cars (not trucks) practical. Maybe this is just a demo rather than serious competitor to EV.
Fast 'charging' seems to be the big one. Also for larger engines (like trucks) you should get lower total weight compared to batteries.
When the 4860 cells are used in the structural battery pack, I recken electric semis will have a good power to weight ratio too.
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.
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-w...
In any case, the only difference between the two models is the amount of time it takes before the car exhausts itself maintaining the battery.
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 :)
I think your numbers are off by at least two orders of magnitude.
Let's say an average BEV travels 20000 miles per year and that it consumes 400 Wh/mile. Traveling 20k miles per year takes about 21 days assuming 40 mph average speed.
If we assume the car is charging the rest of the time, average power required is (400 Wh/mile * 20000 miles) / (1 year - 21 days) = 0.968 kW average charging power!
That's quite a bit less than 250 kW per car (well, 1 MW per 4 cars) you suggested! It'd still be below 2 kW, even if the car is charging just 50% of the time it's not in use.
Other way to think about is charging from empty to full battery with 11 kW of power: (80 kWh) / (11 kW) = 7.27 hours.
Please also remember charging the battery full would be a rather rare scenario. I'd be surprised if you need even 10 kW power allocation for each 4 cars being charged — 1% of what you suggested. Simply because the batteries in most of the cars are full most of the time!
My personal experience of driving electric cars for many years is that home charging from a Level-1 (120V, 8A ~= 1kW) plug is completely sufficient for all of my in-town driving needs.
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.
10 kW per 4 cars is plenty enough.
I charge overnight a 24 kWh Nissan Leaf (< 10 hours a couple of times a week), and just use a 2.1 kW EVSE to charge at a standard socket on a 16 A circuit breaker.
If those were available at all parking spots in the city (say from city lamps), everybody could have electric cars.
This is 'batteries pollute the environment too" FUD all over again.
I'm very much for EVs instead of fossil cars, but the argument that you don't need fast charging because you can charge it while at work or while shopping doesn't stand.
Increasing cost of a parking space 1000 times for extra convenience is not economically feasible. The environmental implications are obious, it simply can't scale, no need to show any math (you made up your numbers first, I don't have anything to compare it to).
But ultimately you can't please everyone. Hydrogen would have similar issues as you can't deploy it everywhere at once, it would take years.
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.
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.
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.
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.
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.
Per kg, but its energy density per litre is very poor. Every modern rocket uses RP1 (kerosene) or Methane (natural gas) for their first stages now.
> It can be refueled in minutes, like gas cars.
If your hydrogen station has 10,000 PSI hydrogen available. A typical station can fill 3 cars per hour quickly. More than that and you have to wait for it to get back up to 10,000 PSI.
> 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.
You can also store "waste" renewable energy in EV batteries.
Yes you can, but the time when solar energy is the most abundant is in the the middle of the day, typically when people are away from home and not charging their cars.
Hydrogen can be stored for years in huge tanks so it is really "on demand". Unlike batteries, tank benefit from the square cube law and therefore makes large scale storage cheaper.
And BTW, personally, I am not convinced by hydrogen cars, but it doesn't look completely stupid either.
However hydrogen needs high pressure tanks and fuels cells to store and use it properly so there is basically no energy density advantage right now in a car, both fuel cells and batteries are increasing in energy density due to R&D not sure which will win out it the end. My current opinion is batteries are simpler in every way and have good enough energy density.
All the current cars also need a lithium buffer battery because the fuel cell can not put out enough burst power nor do regenerative braking.
(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).
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.
DCFC infra today is way better than the H2 infrastructure, and by quite a lot. Good luck holding your fingers.
Much smarter to compare total cost of ownership, and then the ociture is very different
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).
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.
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%....
These are not compelling numbers. Ideally you'd want something safer, not a few times more dangerous.
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.