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profloater
2017-Dec-09, 03:35 PM
I have just been reading in wired magazine about Toyota and its plans to make a hydrogen car. The Mirai, meaning future, is already an actual car with a range of 650 km. The conceptual snag is that most hydrogen today is produced from fossil fuels. So my guess is that electric will win because of the development of solar power which converts to electricity more easily than to hydrogen. Of course this car uses a hydrogen fuel cell to produce electricity and one advantage is that if the hydrogen infrastructure is produced , then refuelling would be as fast as current liquid fuels. If a small company was doing this it might seem a foolish venture but Toyota has an impressive track record.

WaxRubiks
2017-Dec-09, 03:58 PM
yes, the recharging time on electric cars has always seemed like a deal breaker to me.


Solar hydrogen production with electrical-to-hydrogen conversion efficiency of 52% is demonstrated using a simple ∼0.7%-efficient n-Si/Ni Schottky solar cell connected to a water electrolysis cell.

https://www.sciencedirect.com/science/article/pii/S0360319916300039

52% seems quite good.

Ara Pacis
2017-Dec-09, 04:03 PM
If various recent claimed breakthroughs in battery technology (https://www.wired.com/story/bill-joy-finds-the-jesus-battery/) are true, hydrogen won't be able to compete.

swampyankee
2017-Dec-09, 04:36 PM
I have just been reading in wired magazine about Toyota and its plans to make a hydrogen car. The Mirai, meaning future, is already an actual car with a range of 650 km. The conceptual snag is that most hydrogen today is produced from fossil fuels. So my guess is that electric will win because of the development of solar power which converts to electricity more easily than to hydrogen. Of course this car uses a hydrogen fuel cell to produce electricity and one advantage is that if the hydrogen infrastructure is produced , then refuelling would be as fast as current liquid fuels. If a small company was doing this it might seem a foolish venture but Toyota has an impressive track record.

Hydrogen-fueled internal combustion engines are certainly possible, although they've not been readied for production, and a tiny Rankine cycle hybrid would certainly be feasible, albeit maybe not cost-effective. My suspicions is that any hydrogen-based car won't come out of a US car company, which seem to have become quite averse to the sort of R&D required for such a technological advance.

Swift
2017-Dec-09, 04:38 PM
Thread moved from OTB to S&T

profloater
2017-Dec-09, 05:52 PM
If various recent claimed breakthroughs in battery technology (https://www.wired.com/story/bill-joy-finds-the-jesus-battery/) are true, hydrogen won't be able to compete.

So a solid that conducts ions, like an osmotic membrane, that is a new class of materials. We must watch out for more news like that.

Swift
2017-Dec-09, 08:11 PM
So a solid that conducts ions, like an osmotic membrane, that is a new class of materials. We must watch out for more news like that.
Solid ionic conductors, also know as solid electrolytes, are not a new thing. My undergraduate thesis from 1980 was part of work done in Prof. E. Banks group on a group of materials based on ZrP2O7 and ZrV2O7, doped with lithium and sodium. The pyrophosphates were ionic conductors and the pyrovanadates were mixed conductors (ions and electrons).

And they are only some of many other such materials (review lecture from Ohio State U. (https://cbc-wb01x.chemistry.ohio-state.edu/~woodward/ch754/lect2003/ioniccond_lect26.pdf)).

The problem is that none of these materials have been quite good enough for commercial applications. Either their conductivity is too low, they are not stable enough, or they only have sufficient conductivity at elevated temperatures. The linked article from Ara Pacis was pretty vague, so it is hard to say if they have overcome these difficulties.

The Backroad Astronomer
2017-Dec-09, 10:21 PM
yes, the recharging time on electric cars has always seemed like a deal breaker to me.



https://www.sciencedirect.com/science/article/pii/S0360319916300039

52% seems quite good.
The distance issue is the deal breaker for me. Everyone is kind of spread out in area of the world.

WaxRubiks
2017-Dec-09, 10:51 PM
The distance issue is the deal breaker for me. Everyone is kind of spread out in area of the world.

Many parts of the world don't have a very developed electrical power distribution network, as well.

The Backroad Astronomer
2017-Dec-09, 10:55 PM
Many parts of the world don't have a very developed electrical power distribution network, as well.
Minor thing It as suppose to be in "this part of the world", in my last statement.
Another is, so you have been here.

The Backroad Astronomer
2017-Dec-09, 11:13 PM
I have thought that there will a mix of vehicles in the future.
There will cars just used by uber, lift and taxi firms that will be short range probably electric or hydrogen, probably autonomous.
There will transport trucks probably traveling in convoys with a couple of drivers/mechanics just in case something happens.
People in rural areas probably will drive something like suv/truck and until they get range like gasoline engines they won't electric or hydrogen,maybe more hybrid types.
There will be some in smaller centers and people who travel to the country a lot will drive there own cars.

WaxRubiks
2017-Dec-09, 11:29 PM
Minor thing It as suppose to be in "this part of the world", in my last statement.
Another is, so you have been here.

I was thinking about places like large areas of Africa.

The Backroad Astronomer
2017-Dec-09, 11:49 PM
I was thinking about places like large areas of Africa.
That to but there places around here that when there is a bad snow storm the power gets cutoff for a few days to a week.

schlaugh
2017-Dec-10, 03:57 AM
Many parts of the world don't have a very developed electrical power distribution network, as well.

Perhaps partly addressed by solar charging stations. Envision an Indian village and a community power plant that could service multiple vehicles at one time. Or solar panels on the roofs of apartment blocks in Mumbai or Bangalore.

Itís only time, money and willpower.

Ara Pacis
2017-Dec-10, 03:29 PM
The great thing about electrics, is that they can recharge anywhere there is electricity, even from solar cells, or in a town with some sort of generation plant, even if it's not connected to a continent-wide grid. Moreover, with a grid, electricity can be delivered more quickly and reliably than hydrogen. Until hydrogen can be mined from the ambient atmosphere, it won't be able to match the electric paradigm.

WaxRubiks
2017-Dec-10, 04:23 PM
The great thing about electrics, is that they can recharge anywhere there is electricity, even from solar cells, or in a town with some sort of generation plant, even if it's not connected to a continent-wide grid. Moreover, with a grid, electricity can be delivered more quickly and reliably than hydrogen. Until hydrogen can be mined from the ambient atmosphere, it won't be able to match the electric paradigm.

As usual, I think there are many solutions to the problem, not one or the other. Sure you can generate electricity in all sorts of places from solar panels, but it is easier to transport liquid hydrogen.

swampyankee
2017-Dec-10, 04:53 PM
The distance issue is the deal breaker for me. Everyone is kind of spread out in area of the world.

What area of the world is that?

The Backroad Astronomer
2017-Dec-10, 05:57 PM
What area of the world is that?
Southwestern New Brunswick, there are spots were you can go 10-15 minutes between houses. The nearest cities to my town are about 120 km to 150 km away so electric cars are not really practical around here. There are places with a lot less population density then that in Canada.

swampyankee
2017-Dec-11, 01:46 AM
Southwestern New Brunswick, there are spots were you can go 10-15 minutes between houses. The nearest cities to my town are about 120 km to 150 km away so electric cars are not really practical around here. There are places with a lot less population density then that in Canada.

I figured "rural," although I've also heard the same argument from people with a ten minute commute and the longest drive they take is less than 30 miles.

The Backroad Astronomer
2017-Dec-11, 01:50 AM
In general electric cars make sense but until electric vehicles have the energy density of that gasoline there will be exceptions, that was the real part of my argument.

Jens
2017-Dec-11, 03:55 AM
As usual, I think there are many solutions to the problem, not one or the other. Sure you can generate electricity in all sorts of places from solar panels, but it is easier to transport liquid hydrogen.

Easier to transport liquid hydrogen? I guess it is pretty easy, if you forget about the making it cold part and the blowing up part.

WaxRubiks
2017-Dec-11, 07:00 AM
Easier to transport liquid hydrogen? I guess it is pretty easy, if you forget about the making it cold part and the blowing up part.

hydrogen doesn't have to be kept cold, although it appears that it can decompress explosively..(?)...so it needs a strong containment vessel...but it seems they're working on it.

swampyankee
2017-Dec-11, 10:13 AM
hydrogen doesn't have to be kept cold, although it appears that it can decompress explosively..(?)...so it needs a strong containment vessel...but it seems they're working on it.

Any highly pressurized gas can "explode" if the container suffers a brittle failure. Modern pressure vessels are constructed with metals that won't do that, or they're constructed with composites.

Overall, hydrogen is really not that much more difficult to handle or transport than gasoline.

profloater
2017-Dec-11, 09:54 PM
The toyota uses carbon reinforced resin, it's a good choice imo carbon fibres show zero fatigue and graceful failure. A bullet in the tank causes a leak which blows off upwards unlike petrol or natural gas.
They must think the hydrogen infrastructure is viable. If you ignore the fossil fuel downer, hydrogen should be cheap. For city use it moves the pollutants out of town. Personally I still think electric will still win before they can persuade cites to set up hydrogen gas stations. For airplanes it might prove the next technology. For airships it could make a comeback, helium is expensive and limited.