Ban sales of gas-powered cars?

The problem with hydrogen is building the infrastructure is harder than expanding electrical infrastructure. So for consumer cars... not sure it's great idea. For transit, transport/shipping/delivery trucks though... might be a good fit.

Synthetic is interesting. If only from the perspective of allowing existing ICE cars to potentially be greener than they are now and just work with little to no modification. Great to help with transition, or allow something like a classic car to keep going.

 

Hydrogen feels like the endgame goal with EVs just being a stopgap

 

Depends infra is easier for Hydrogen when you go to remote areas compared to EV's and less expensive also. You won't need hydrogen stations as nearly often also compared to EV and the time those are taken is lesser as per.

At least here we are required to have EV charging station every 50km or so and 150km for Hydrogen and when there is no infra to begin with it starts to get hard.

 

Green energy > Electrolysis to create hydrogen > Extreme compression > Physically transporting it > Convert to electricity in the car > Drive the car

vs

Green Energy > Power the grid > Charge the car from the grid > Drive the car

It simply does not make sense to add in an additional loss and conversion process that is totally unnecessary. An EV runs more or less directly off the renewable powerplants we build at quite low conversion losses. Hydrogen requires the same green energy powerplants EVs will run off of, but it requires significantly more of them because of the relative lack of efficiency in creating a gas, transporting it, then converting it to electricity to move a car. We already have the electricity. Skip the extra steps, they're silly.

 

The production of the batteries are far from green however and have limited lifespan - that's the downside to EVs

 

I agree with this.

Hydrogen for passenger cars is a no go because of the lack of infrasctructure and because of how hard it is to store it.

But for trucks and buses it could work. And if it can be used in airplanes and ships, even better.

And i also agree that synthetic fuels would bw a great solution for ICE cars, the question is if they are economically viable at a very large scale.

 

The emissions related to mining and producing batteries are reducible to a significant extent. There's nothing inherent about the mining that releases CO2, it just requires machinery to mine and transport which currently burns fossil fuels. Converting each step of the mining and transportation chain to electric or other CO2-less alternative reduces and basically eliminates this. This is something that will have to happen, regardless, hydrogen or not.

 

Downside but still irrelevant as all these studies that measure EV vs ICE vehicles in terms of emissions factor production/recycling/disposal in and as Reardan said as the process moves to EV it just gets even more efficient.

 

The infrastructure is mostly in place for hydrogen.
With the reduction of petrol and diesel as fuel sources the refuelling pumps can be converted to hydrogen refuelling.
These will also be refilled with tankers. No infrastructure change other than how hydrogen is generated/stored.
Much later there may be underground piping but the tech isnt ready yet, and when it is, it will need serious long term evaluation. Small areas will no doubt be involved in the trials.

Synthetic fuels will need to be less problematic to public health or they wont have much chance to become mainstream.
If that can be managed there is a chance but it must still compete with the efficiency of battery or hydrogen EVs which also compete with each other.


A lot must be considered when choosing a motor...
(ended up writing a lot more than intended which lost the plot a little. Was supposed to be a % comparison but I've had enough for now, got things to do )

Synthetic fuel (covers some use of fossil fuel too):
30% efficient engines.
Engine weight (larger cc and/or diesel being heavier): 4 cylinder 90 - 160kg, 6 cylinder 140 - 200Kg, 8 cylinder 180 - 320Kg.
Transmission weight (gearbox+clutch+drive shafts): 45 - 181Kg.
Creating synthetic fuel could be a major issue: running a Synth fuel car needs approx 4x more energy overall than required for a Battery EV.
Ability to generate enough synthetic fuel, only 12% of all gasoline predicted in the US by 2030.
May get less mpg from synthetic fuels.
May still cause public health issues.
No infrastructure changes other than generation of synthetic fuel.
Can travel 400+miles before refuelling and refuelling is fast and easy to locate.

Hydrogen:
Hydrogen generation loses 20 - 30% of the energy to heat, then compression and storage loses 10%.
Fuel cells are currently 70% efficient converting hydrogen to electricity = 30% loss.
Works out overall 30 to 40% efficient with technology as of 1yr ago.
Cars are lighter (much lighter for high performance) mostly due to removal of the ICE+transmission (see Synthetic fuel above for weights) or EV Battery (400Kg+ see Battery EV below) although countered a little by the 100Kg+ for a cars hydrogen tank and the motor weight vs an ICE car.
Can travel approx 300 miles with 5Kg fuel and a 100Kg tank (I read something near this a few days ago), tank weight increases with fuel contained.
Currently very few places to refuel, needs major investment converting fuel stations.
Refuelling is fast.
Less tyre wear/noise due to lighter weight.
No public health problems.

Battery EV (BEV):
Battery weight, for Tesla cars: 450 - 625Kg. Adds considerably to overall weight, increases tyre wear/noise, reduces efficiency.
Battery life: Varies with ambient temp, how low % its used to and how high % its charged to, how hard its driven. It will last longer with a 30 - 70% max charge, above 90% isnt best (except vehicles that are battery use restricted as part of pricing policy). Current batteries are projected to last around 200,000 miles so not a large consideration for most unless buying 2nd hand.
Charging efficiency: varies with ambient temp, charge rate. Todays best is around 96%. Many are reporting around 88%.
Batteries lose approx 2% of max power each year. If mileage they can do is critical to you this should be factored in.
Motor efficiency: varies with rpm and torque, generally 90 to 94% with sensible driving.
Required mileage needs to considered, varies a lot between vehicles and reduces in cold weather. Is improving with new developments.
Charging is very slow and inconvenient unless using a fast charger which reduces battery life a little and is still slow and inconvenient compared to refuelling the other fuel types.
Not enough chargers, fast chargers especially. They can be in inconvenient places when you have things to do due to long charge times.
Charging at home is cheap but slow, may need overnight. Charging on the road can cost a lot more, especially for a fast charge.
BEVs are mostly limited in top speed. I assume to prevent the warranty costing the mfr too much.
No public health problems.


Sources of info
https://www.fluxpower.com/blog/hydrogen-fuel-cell-efficiency-how-does-it-compare-to-lithium-ion
https://mechanicbase.com/engine/car-engine-weight/
https://wrenchguru.com/how-much-does-a-transmission-weigh/
https://www.forbes.com/sites/jamesm...-wont-save-the-planet-so-dont-say-they-could/
https://themotordigest.com/how-much-do-tesla-batteries-weigh/
https://teslamotorsclub.com/tmc/threads/charging-efficiency.122072/
https://teslamotorsclub.com/tmc/threads/ideal-charge-rate.73833
https://x-engineer.org/ev-design-electric-motor/

 

worth mentioning transmission losses from the power generation to the consumer is greatly dependent on on the distance between the two , anywhere from 8-15%, but can be higher in underdeveloped countries.

some additional sources
https://blog.se.com/energy-management-energy-efficiency/2013/03/25/how-big-are-power-line-losses/
https://cogeneration.pro/energy-losses-and-inefficiencies-in-the-traditional-power-grid/
https://arstechnica.com/science/201...ns-due-to-electricity-loss-on-the-power-grid/

The power grid isn't just a blackbox, it has inefficiencies and scaling problems, its not that simple unfortunately. The only green energy that scales big is nuclear, everything else doesn't do much other than reduce load/dependence on other power generation opportunistically, since ATM there is no grid level energy storage which can buffer things like solar and wind.

the total efficiency doesn't matter as much as total supply so to speak
if the grid can only provide <amount> watts and if you need more than that , your kind of stuck, Hydrogen on the other hand can be used to store way more energy for a lower cost than any battery. which potentially makes things like solar and wind actually viable as 24/7 energy sources.

currently energy is stored as barrels of oil or LNG in reserves , which can be bought, sold and redistributed, Batteries simply aren't up to the task to replace that. Hydrogen could fill role that by comparison.

 

China is laughing all the way to the bank!



no new manufacturing jobs for you...!

 

I dunno where this idea that hydrogen is hard to store comes from, you can do it with steel tanks, which are very cheap compared to a battery, The part people don't like is the high pressure, but I think the point is moot since we've been making high pressure tanks for i dunno a hundred years? maybe longer? and they are designed not to explode and fail gracefully .

 

The main reason it's not used to power cars is it's volatility. High pressure tanks are not a problem as long as they are stored somewhere, but having one under your seat is whole different story.

 

If it fails gracefully, its not really an issue, it just vents to atmosphere, I get that people don't like the idea of having a high pressure vessel in their car, but is the risk really that high? especially compared to an ev battery? I tend towards no. everyone has seen what happens to soda bottle when it is over pressurized, but a metal or composite tank that is designed to not catastrophically rupture , is a whole different thing.


i'll add an example to better visualize the difference, consider if a tank was made of cast iron vs a mild steel, the cast iron tank is going to explode like a bomb, because it is brittle sending chunks. where as the mild steel tank may crack and deform instead with no fragments, both fail but one is infinitely more dangerous than the other.

 

No it's not, they have tested these storage tanks by literally shooting them with bullets they pierce the tank and the hydrogen vents to atmosphere with no issue and the tank stays in tact, as long as their is no spark it isn't going to do anything so pretty much the same scenario as a petrol tank and it's a small tank I am sure there is any number of factors that could be implemented to isolate any potential ignition sources from the tank similar to systems they use in modern ICE vehicles.

On the other hand a BEV is mostly made up of something that only requires a tiny bit of damage to one of the internal cells to turn the entire vehicle in to a raging inferno in 30s. I find it odd that people would be perfectly happy with driving a BEV but have a major issue with a hydrogen powered car.

I know why people have an issue with it, a historical example of what happens when you get things wrong (the Hindenburg), it's the same faulty logic that people who are against Nuclear Power use when they quote Chernobyl.

 

Im really looking forward to "gas powered" cars being banned from the roads... sooo much less noise from all the morons who make their cars as noisy as possible.

 

Thanks for the additional info.
Good valid points.

I forgot to state under the Battery EV section:
Batteries lose approx 2% of max power each year.
If the mileage they can do is critical to you this should be factored in.
I'll add that to my previous post.

 

Your also applying some faulty logic yourself. Hydrogen is considerably more flammable and combustible than gasoline or an EV battery. Yes an EV battery if damaged can certainly light up. But comparing that to the highly flammable gas of Hydrogen borders on a false equivalence.

 

Where do you live? Might just do a few night drives in your neighborhood with my straight piped S60R.