Why not use electricity directly instead of hydrogen

In summary: But for gas, I know that 70 L of gas weights 50 kgf and you can add about 20 kgf for the tank, fuel...In summary, the main problem with using hydrogen as an alternative energy source is that it is more difficult to store and transport than gasoline. However, the main benefits of using hydrogen include that it has the same energy as gasoline and it is lighter than gas.
  • #71
HyperTechno said:
Well it needs an expensive totally new infrastructure which can make that very unpractical.

Many cost estemites dishonestly assume that you'll start by tearing up a brand new road to put wires in. But highways have to be rebuilt and replaced on a regular basis. If you add wires when the road is scheduled to be redone anyway, the cost is magnitudes lower. You pay for the electricity the same way you pay for the asphalt. Or include some kind of meter in the car.
 
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  • #72
Electrified road transport would not make any sense done on the basis of a bit here and a bit there whenever the roadway needs maintenance.
There would need to be complete routes between cities (or within cities), otherwise it's a pointless exercise.
 
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  • #73
You don't need complete routes. You just need the gaps to be less then the battery range of the car.
 
  • #74
Algr said:
Many cost estemites dishonestly assume that you'll start by tearing up a brand new road to put wires in. But highways have to be rebuilt and replaced on a regular basis. If you add wires when the road is scheduled to be redone anyway, the cost is magnitudes lower. You pay for the electricity the same way you pay for the asphalt. Or include some kind of meter in the car.
Shifting the transportation system (US ~250 million vehicles) to an alternative is much more difficult than, say, switching from land-lines to mobile phones in communications back in the 1990s. The problem with transportation is that a vehicle owner rightly expects the vehicle to be operable anywhere on the continent, so that a notional electrified road system has to be available everywhere, nearly simultaneously. When mobile phones and networks were under early development, one always had the fall back of using the land lines when roving out of the area. And an investment of a few hundred dollars in a phone versus several tens of thousand dollars in a vehicle made the lack of availability more tolerable. That is, electrified roads in east coast city A may accommodate an e-vehicle owner there. The same owner who moves to west coast city B can't tolerate a useless vehicular there, with road updates a decade or two away.
 
  • #75
Algr said:
You don't need complete routes. You just need the gaps to be less then the battery range of the car.
Same all-at-one problem as rootone mentioned, just a bit smaller scale.
 
  • #76
mheslep said:
. The same owner who moves to west coast city B can't tolerate a useless vehicular there, with road updates a decade or two away.

But none of those vehicles are ever useless. Right now the lowest cost (Total cost of ownership) car in the US is one of Toyota's Priuses. Adding a road pickup to that car would add maybe $500 to the cost of the car, and then you'd save money with reduced fuel costs. All electric cars with 80 mile ranges are also selling today. Even a single electrified highway would make such cars more appealing to people who drive on that highway every day. And you can actually sell your car if you move. These problems aren't as insolvable as you make them out to be.
 
  • #77
Algr said:
Many cost estemites dishonestly assume that you'll start by tearing up a brand new road to put wires in. But highways have to be rebuilt and replaced on a regular basis. If you add wires when the road is scheduled to be redone anyway, the cost is magnitudes lower. You pay for the electricity the same way you pay for the asphalt. Or include some kind of meter in the car.
So, how the cars receive electricity?
 
  • #78
mheslep said:
Not only. A multi MW utility connection and a multi MW electrolyzer and a multi MW compressor are needed. To appreciate the scale involved, start with the fact that *one* gasoline pump delivers 20 MW of chemical energy, a ten pump highway station perhaps 200 MW. Alternative transportation systems may be a little more efficient, but must operate on the same order of magnitude of energy consumption.
Still, won't the local Extraction be more efficient and convenient than a centralized Extraction facility that needs transportation? The initial costs may be higher but considering the difficulties in transportation, wouldn't that be more convenient?
 
  • #79
HyperTechno said:
Still, won't the local Extraction be more efficient and convenient than a centralized Extraction facility that needs transportation? The initial costs may be higher but considering the difficulties in transportation, wouldn't that be more convenient?
Maybe so. Either way, installing an national h2 fueling system is going to be very expensive.
 
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  • #80
Algr said:
But none of those vehicles are ever useless. Right now the lowest cost (Total cost of ownership) car in the US is one of Toyota's Priuses..
The hybrid Prius available in the US does not have a full power electric motor. An electrified highway doesn't add much value to such a car.

For that matter, any plug in hybrid that does have a full power e motor (e.g. Volt) pretty much solves the clean transportation problem, or 90% of it anyway, and I expect much more cheaply than electrifying all the highways, even incrementally.
 
  • #81
mheslep said:
start with the fact that *one* gasoline pump delivers 20 MW of chemical energy

Also consider that the pump is not running 24/7. It will only be at 20MW for a small percentage of the time. You still end up with a rather large number for the average daily usage of even a single pump. The wire to wheel efficiency is going to be embarrassing for hydrogen in any case.

BoB
 
  • #82
mheslep said:
Maybe so. Either way, installing an national h2 fueling system is going to be very expensive.
Yeah. Of course it's expensive. About 2 million $ per filling station. One reason for HFCV to progress much slower than the pure Evs.
 
  • #83
HyperTechno said:
Yeah. Of course it's expensive. About 2 million $ per filling station. One reason for HFCV to progress much slower than the pure Evs.
Much more than that for a station with local h2 production, equivalent to the energy flow of an existing gasoline station.
 
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  • #84
mheslep said:
Much more than that for a station with local h2 production, equivalent to the energy flow of an existing gasoline station.
Yeah. And I don't think the existing hydrogen filling stations have the energy flow of a gas station.
 
  • #85
  • #86
Algr said:
Very impressive technology. But still the cost would be insanely high, which could limit that to R&D. How ever who knows, could be successful too. But the initial higher costs could keep this from happening for a long time. I think so. By the way the article doesn't give any information related to the rate of charging... What do you presume about those?
 
  • #87
Algr said:
Yes it does:
https://en.wikipedia.org/wiki/Hybrid_vehicle_drivetrain#Full_hybrids

Plug in hybrids and pure electrics benefit because range is extended on the highway, where it matters most.
http://money.cnn.com/2015/08/18/technology/uk-electric-cars-roads/

Regarding charging an EV from the road while driving:

But fast charging batteries reduces their life-span. Nissan says fast DC charging will reduce battery life.

So in round numbers, a Nissan Leaf has a range of ~ 80 miles, and takes 4 hours to charge with a 220/240-volt 40 amp supply (7.7 kW allowable draw - 6.6 KW charger). So at 55 mph, it takes ~ 1.5 hours to discharge the batteries. So even being in contact with that high rate of charging current 100% of the time wouldn't keep the battery charged up. You are using energy at 2.6 x the rate you are getting it at. And transferring larger currents is hitting practical limits.

An occasional lane along the route won't have much impact on range at all. Let's see, 80 miles range in 4 hours charging provides a re-charge rate of about 20 miles / per charge hour. I'm still on my first cup of coffee, there might be some interaction or secondary effect I'm ignoring, but I think that means that if you had access to a charging lane for 1/4 of the time (one hour out of your 4 hour trip), you'd get an extra 20 miles of range?

That's 20 miles out of 80 miles of charge lane length that you would need. That's a lot of infrastructure for marginal gain it seems.
 
  • #88
Catching up with some older posts:

jack action said:
But the objective of having an electric car is not cheaper transportation, it is lower emissions. ...

CraigHB said:
I think people should take some personal responsibility for the state of the environment, ...
It's reasonable to care about the environment enough to spend more than I would normally. ...

I don't know how much difference there is between driving an electric car and a gasoline car In terms of the environment and pollution. After all the majority of electrical production in the US comes from burning natural gas and coal. The energy used to power an electric car still comes from a source that pollutes. I'd just be trading one for another. Now if clean ways of generating electricity become the majority, going with electric could make more of a difference.

This is key, and I didn't see it addressed much in this thread. The batteries in EVs just store energy that was produced, so from a pollution view, it is the production of that electrical energy that matters.

And EVs create extra demand on the grid. And the average mix of renewable energy on your grid matters little. Since we are already using all the nuke energy and renewable energy available to us, that extra energy demand will be produced by fossil fuel (nat gas turbines if intermittent, and likely by using more coal if the demand is predictable).

If we occasionally have an excess of wind energy at night, that helps - but it is unlikely that the excess will occur regularly enough to power a very significant amount of a large EV fleet. And even a small amount of back-fill by coal makes a huge difference in overall pollution (coal is far dirtier than nat gas - particulates, Nox, Sox, acid rain effects).

Same with hydrogen. It takes energy to get it in a form that a car can use.

CraigHB said:
... Though sticking it to the evil oil companies would be some compensation. ...

But the hydrogen for fuel cells is currently produced from hydrocarbons, the hydrocarbons produced by those 'evil oil companies'. Same thing if you generate hydrogen from electrolysis - that takes electricity, so the same demand issue I outlined above. Going hydrogen for energy storage won't change that, it will still use oil or nat gas from oil production.
 
  • #89
NTL2009 said:
Regarding charging an EV from the road while driving:

But fast charging batteries reduces their life-span. Nissan says fast DC charging will reduce battery life.

If you are on the road, you are not using the power to charge the batteries, but to power the motor. So the range extension can easily be longer than the amount you actually drove on powered roads. Neither of us have numbers about how much this costs, but the fact that the brits are trying this out suggests that it isn't much more expensive than a regular road.
 
  • #90
Algr said:
If you are on the road, you are not using the power to charge the batteries, but to power the motor. So the range extension can easily be longer than the amount you actually drove on powered roads. Neither of us have numbers about how much this costs, but the fact that the brits are trying this out suggests that it isn't much more expensive than a regular road.

Yes, but I think it is still a lot of power. Check my math, but a Nissan Leaf uses ~ 280 watt-hours per mile ( 30kWh battery gets 107 mile range).
At 55 mph, you get: (55 miles / hour) x (280 watt-hours / mile) = 16.5 kW ( the miles and the hours cancel, leaving watts)

So if I did that right (seems roughly right, as 16.5kW ~ 22 HP, and that's roughly what it takes steady state to propel a vehicle at 55 mph), that means you need 75 amps at 220 volts just to propel the vehicle, not charge the battery. That seems like a lot of power to transfer wirelessly. So if you had 25% of the highway with this high power installed, you would only increase your range by 25%.

Is that worth the expense? Sounds very questionable to me.

I could maybe see this approach for intercity buses/taxis? Wireless charging embedded at most stop lights and bus stops? Would it make sense to charge while you are waiting? A bus can pull into the bus stop space for most red lights, but sometimes traffic would block them.ooops, are we too far away from the original topic (hydrogen)?
 
  • #91
NTL2009 said:
ooops, are we too far away from the original topic (hydrogen)?

Could be. A new topic should start with some hard data though. Electrifying the highways is a small project compared to getting the highways build in the first place.
 
  • #92
Algr said:
Plug in hybrids and pure electrics benefit because range is extended on the highway, where it matters most.
How is that hybrids require any more range? How do they obtain any cost effective benefit from an increase beyond the current ~400 miles/tank of gas, which btw can be replenished in 4 minutes at any of a couple hundred thousand US filling stations?

Pure electrics would benefit, sure, but the very nature of the electric roads proposals shows the flaw in pure electrics, one that hybrids don't share.
 
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  • #93
mheslep said:
How is that hybrids require any more range? How do they obtain any cost effective benefit from an increase

Because it costs less to run a hybrid from electricity than gas. Read up on the first coast-to-coast trip by car, and how hopelessly impractical it was compared to the trains that were available. No one looked at that and said cars are hopeless stick with trains. Instead we saw opportunities and build a highways system. That's how change happens.
 
  • #94
Algr said:
Because it costs less to run a hybrid from electricity than gas.
Not in this case. Yes, US electricity at 12¢/kWh or 4¢/EV-mile on the existing residence connected grid fed to an existing plug-in via cables is cheaper than gas per distance traveled (5¢/mile @40 mpg/$2/gallon). The cost of electrifying highways, adding induction loops to new plug-ins,and the losses of induction very probably make the total cost of highway electricity higher than gasoline. And so again, to what benefit, for the 5% or so of driving that's long distance?

It seems to me the only rationale would come from proving, via production experience, that pure EVs with large batteries are substantially cheaper than comparable dual drive train, hybrid vehicles. So far, that's not the case. Further, a cheaper than hybrid EV works only if some kind of adoption model manifests where EV owners are not inconvenienced in areas with no highway electrification. Other answers requiring people to change behavior for acceptance, i.e. "sell your car", are outside of market economics based solutions.

Read up on the first coast-to-coast trip by car,
I'm familiar.
and how hopelessly impractical it was compared to the trains that were available. No one looked at that and said cars are hopeless stick with trains. Instead we saw opportunities and build a highways system. That's how change happens.
That's not the history of the 1950s built highway system in the US, which was built for i) national defense reasons, and from ii) localized support for highway funding that stood to benefit from passing highway traffic.

Change has occurred in this case via hybrids.
 
  • #95
Since you brought the idea of electrified lanes, why don't you start a new thread on the matter so that we can discuss about it more broadly and freely.
Thanks.
 
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  • #96
Algr said:
Could be. A new topic should start with some hard data though. Electrifying the highways is a small project compared to getting the highways build in the first place.
Since you brought the idea of electrified lanes, why don't you start a new thread on the matter so that we can discuss about it more broadly and freely.
Thanks.
 
  • #97
Hey there , I'd like to add my conclusion or , what I vision as the propulsion system of the future vehicles will be. . . . Well that will most unlikely be hydrogen , probably it will be pure electric . Why, consider the batteries vs HFC s. The history and the experience the human civilization has had with the batteries is far great than that of HFC s. And batteries are being used all over the world . In all kinds of mobile applications , backup systems, pure Evs and hybrids , rovers and drones and etc. Any advance in battery technology in any of these sectors can contribute to others . And a lot more is invested and are being invested in various types of battery technologies and many new battery technologies have discovered and are being developed . And also lithium battery technology too is being developed .http://feeds.sciencedaily.com/~r/sc...gy/fuel_cells/~3/zyuXLz7DBLc/161108114137.htm

http://feeds.sciencedaily.com/~r/sc...gy/fuel_cells/~3/LA0A4awnPNk/161026102701.htm

http://feeds.sciencedaily.com/~r/sc...gy/fuel_cells/~3/F7Od9oV8PbQ/161024104227.htm

http://feeds.sciencedaily.com/~r/sc...gy/fuel_cells/~3/_7URtdM7buw/161018194231.htm

http://feeds.sciencedaily.com/~r/sc...gy/fuel_cells/~3/A3p06raOCEo/160915090014.htm

Plus in another article that I've read (I couldn't find it on the net within the time I had to write this post sorry ) , There was a technology to improve the life time of the lithium batteries a lot . The researchers have practically tested that , 200000 (yes it's 200,000) recharge cycles within a month with only 0.23% of battery degradation . Impressive . Very impressive .
So with all these plus the vast infrastructure the pure Evs have relatively to HFCVs, I don't think there will be a good future for HFCV s. The only advantage they have is quick refilling . But that too is being obtained by the evolving battery technologies .
 

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