Why not use electricity directly instead of hydrogen

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The discussion explores the viability of hydrogen as an alternative energy source compared to direct electricity use for powering vehicles. Hydrogen is noted for its clean emissions, but current extraction methods often rely on fossil fuels, raising concerns about its sustainability. The conversation highlights the advantages of hydrogen, such as quick refueling times and high energy density, but also addresses significant challenges, including storage difficulties and safety concerns due to high-pressure requirements. While hydrogen fuel cells offer potential, they face technological and economic barriers, making electric vehicles a more immediate solution for reducing emissions. Ultimately, the debate underscores the need for advancements in both hydrogen and battery technologies to achieve a sustainable energy future.
  • #31
However, there hasn't been enough Pt mined and refined in all history.
 
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  • #32
Batteries are well on their way in development right now and I think they have the most potential (there's a pun there) to provide a zero emission future. As stated there's a big problem with the time it takes to recharge. There's a big difference putting a car on a charger for several hours versus fulling a tank of fuel in a few minutes. Though it's possible advances will allow very high charge rates, I don't think it will ever be possible to charge a battery in only a few minutes. There's simply a limit to the current a wire can carry. It's always going to take at least a couple hours to recharge even with currents at the limit of what wires can carry and what sources can supply. It's not going to be possible to put energy back into a battery any faster than it can be taken out.

I've thought for some time that a really good solution might be the combination of a fuel cell and a storage battery. In that case a fuel cell can run long term at a relatively low power output to keep batteries charging. Batteries can provide energy at a much greater rate than a fuel cell can provide standing alone. That allows the car to reach high peak power outputs as required. The two could provide range even further than a gasoline car having a tank of fuel plus the energy capacity of a battery. When the car is resting, the fuel cell can keep running to supply charge to the battery. Though this again falls back to the high cost of fuel cells. They're just too expensive for public consumption right now. Though we may be only one breakthrough away from a cheap consumer level fuel cell.

There is the argument that we've already passed the point of no return in terms of pollution and climate change. That should not be a reason to give up though. The sooner we stop adding unnatural chemicals to the atmosphere, the less time it will spend in an unnatural state and the sooner it will return to a natural state. I'm no expert on climate change, but I don't believe it's a situation where once it goes over the edge it never comes back. I think we're still pretty far from a situation where the climate has run away for good.
 
  • #33
mheslep said:
Just a bit outside. Mirai 70 MPa (10kpsi) tanks for 5kg H2 reportedly have mass 87.5 kg (193 lbs). Three layer tanks: glass fiber surface, carbon fiber middle, plastic layer inner.

Sounds similar to the tanks jack action linked to above. When I wrote my post, I was thinking steel cylinder tanks; that shows you how easy it is to be stuck in the existing paradigm. Still, the tanks in your link (near 200 pounds for 5 kg H2) show the storage of hydrogen is more difficult than gasoline.

By the way, how do you guys embed a link to a previous post?
 
  • #34
It seems that a solution to all the long recharge times that batteries have, at least for automotive applications, is to standardize on two or three battery sizes/capacities with standardized connections (physical & electrical), and then build cars that can use them. If this is done smartly, it would then be possible to build automated battery-swapping-stations. You'd drive in, stop for a few minutes, and drive out with a fully charged battery. You'd receive a credit for any unused charge on the battery you drove in with and pay for the net gain. Taken a little further, a smart gasoline provider (Exxon/Mobil, Shell, ...) could add a battery-swap bay to its existing gas stations. In this scenario you wouldn't even own a battery, you'd just pay to use one. Like swapping propane tanks for your gas grill, except the automotive battery swap could/would be automated. This needs no new technology, just smart use of what we already have. Forget your battery-charging-station network, Tesla, build automated drive-thru battery swapping stations!
 
  • #35
phans said:
If this is done smartly, it would then be possible to build automated battery-swapping-stations.

That would be a solution to the charging time problem. It's not without some logistical issues itself. The battery is the most expensive part in an electric car. There would be some large initial costs to build stations and stock batteries in the numbers required to make it practical.

Right now battery technologies and form factors vary widely. Companies generally don't like to share technology so getting them to work together on a battery standard would not be an easy thing to do. Especially since the battery is a big point of competition in electric cars determining range, cost, and performance.

Companies are typically pretty obsessed with minimizing production costs. When dealing with the hundreds of Amps these batteries supply, coming up with a reliable quick release connector and battery housing that can handle thousands of cycles is an engineering problem. It creates extra costs that would not be there but for some kind of quick change standard.

Battery stations are definitely a possible solution, but like any distribution system there's costs involved and some entity has to saddle them.
 
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  • #37
phans said:
It seems that a solution to all the long recharge times that batteries have, at least for automotive applications, is to standardize on two or three battery sizes/capacities with standardized connections (physical & electrical), and then build cars that can use them. If this is done smartly, it would then be possible to build automated battery-swapping-stations. You'd drive in, stop for a few minutes, and drive out with a fully charged battery. You'd receive a credit for any unused charge on the battery you drove in with and pay for the net gain. Taken a little further, a smart gasoline provider (Exxon/Mobil, Shell, ...) could add a battery-swap bay to its existing gas stations. In this scenario you wouldn't even own a battery, you'd just pay to use one. Like swapping propane tanks for your gas grill, except the automotive battery swap could/would be automated. This needs no new technology, just smart use of what we already have. Forget your battery-charging-station network, Tesla, build automated drive-thru battery swapping stations!
It's already been tried, and the attempt already placed a $billion battery swap company (Better Place, Inc) in the ground. As it stands the large batteries require building the car around the battery. Tesla's model S for instance uses almost all the undercarriage for battery. Standardizing the battery package means standardizing all the cars, which won't happen.

Also, battery swap is a difficult proposition technically. The automatic removal/insert must handle the mechanical requirements for a half ton of battery ( and several times that in structural strength) and the high amp electrical connections have to be auto make/break. Most difficult however is that any serious EV needs a thermal management system connected to the balance of the vehicle, which likely means auto make/break fluid connections. That's doable under controlled conditions and has been been done with military aviation equipment, but its expensive. Its not been done in all kinds of weather with the crud that builds up under vehicles.

Battery Swap is something to revisit when battery tech reduces the size several fold.
 
  • #38
gmax137 said:
storage of hydrogen is more difficult than gasoline.
True but storage is a solvable problem. H2 distribution still has no feasible solution, nothing remotely close.
 
  • #39
mheslep said:

It's the numbers. If fuel cells were to become a commonly utilized technology there could be vast numbers of units in use. It wouldn't just be cars either, they have have potential for other applications. That's quite a large amount of some precious mineral. If a catalyst can be developed that does not utilize precious minerals, that would be the solution to a consumer fuel cell in terms of cost and availability of materials. That could be a huge step in moving toward a zero emission future. Even so I think a more practical battery is closer to realization than an inexpensive fuel cell.
 
  • #40
Dual drive train vehicles is a technical solution to net zero carbon emission vehicles, but I doubt an affordable one, i.e. one feasible to the point of mass adoption in the market. The plug-in Ford C-Max Energi costs 25% more than than the C-Max hybrid, and the straight combustion version from Ford (the Focus, same platform) costs half as much as the PHEV. Even the substantial federal tax credit subsidy in the US doesn't grant sufficient balance, as the manufacturers must now consider the needs of the world's largest car market, China.
 
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  • #41
CraigHB said:
That would be a solution to the charging time problem. It's not without some logistical issues itself.
Just comparing the specific energy of gasoline versus batteries shows that you would have to store batteries weighing a hundred times more than the gasoline weight. A typical gas station might have 3*10,000 gallons of gas at 6.3 lbs/gallon. That would be about 100 tons of gas. So the energy-equivalent battery storage would be about 10,000 tons. And that is just the replacement for an average gas station, not the big interstate stations.
 
  • #42
Vanadium 50 said:
Well, if we decide we want to reserve hydrocarbon use for elites to fly their private jets to Davos and decide how much the little people need to sacrifice, well that's not a technological decision.

Yes, we could achieve this with an arbitrary point system called "money" and give only trivial amounts of it to the politically powerless.
 
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  • #43
FactChecker said:
Just comparing the specific energy of gasoline versus batteries shows that you would have to store batteries weighing a hundred times more than the gasoline weight. A typical gas station might have 3*10,000 gallons of gas at 6.3 lbs/gallon. That would be about 100 tons of gas. So the energy-equivalent battery storage would be about 10,000 tons. And that is just the replacement for an average gas station, not the big interstate stations.

You are not counting this right. Assuming 60 kW.h batteries and 10 kW chargers, it takes 6 hours to charge your batteries. If it takes 2 minutes to swap batteries in a single stall, it means only 180 cars would be able to use the stall per 6 hours. After that, you first battery is fully charged and ready to be put in another car. So 180 batteries per stall with, say, 4 stalls per station you need 720 batteries. At 1300 lb/battery, it's about 400 tons only.
 
  • #44
FactChecker said:
Just comparing the specific energy of gasoline versus batteries shows that you would have to store batteries weighing a hundred times more than the gasoline weight. A typical gas station might have 3*10,000 gallons of gas at 6.3 lbs/gallon. That would be about 100 tons of gas. So the energy-equivalent battery storage would be about 10,000 tons. And that is just the replacement for an average gas station, not the big interstate stations.
Batteries can be re-charged.

The number of batteries required at a would-be battery swap station is equal to the charge time of a battery divided by the queue time interval for a swap. That is, if a stored station battery requires 20 min to charge and swap time is four mins, then the station needs five (charging) batteries in stock to swap continuously, once every four mins.
 
  • #45
@jack action and @mheslep , Good points. I stand corrected. And the batteries and recharge station technology could probably be improved to the point that there would be much less "inventory" than current gas stations.
 
  • #46
jack action said:
So 180 batteries per stall with, say, 4 stalls per station you need 720 batteries. At 1300 lb/battery, it's about 400 tons only.

There's also the likelihood that as battery technology improves energy density improves making batteries smaller and lighter. In the last ten years evolving Li-Ion battery technology has pretty much doubled energy density. There's the possibility of some breakthrough that doubles it again in the near future. For example, something like this; http://news.mit.edu/2016/lithium-metal-batteries-double-power-consumer-electronics-0817
 
  • #47
CraigHB said:
There's the possibility of some breakthrough that doubles it again in the near future.
Too late now for the "near future". I suspect that the point that the energy industry is different from the semiconductor industry is about to become quite clear.

One new semiconductor plant could be built with a doubling of fabrication resolution and supply the entire world. Also demand for semiconductor containing goods has been such that products could be thrown away in 2-3 years with replacement by the new. Not so with energy. The single Gigafactory underway by Tesla will double the world's production of batteries, and that factory will lock in mass production of battery technology to no more than incremental improvements for the next half dozen years (as Musk has said). Some 200 factories the size of Tesla's would be required to supply a majority EV worldwide fleet.

Mobile hand held electric devices might benefit soon from a doubling of battery density, but not mass production vehicles which require ~10^4 or 10^5 times the joules of storage.
 
  • #48
It's hard to say what the future will bring. People in positions of authority and power have made blanket statements like that many times only to be proven wrong. What Musk is saying may be true for the cars his company makes, but there's plenty of competition. I would be surprised if some company does not utilize new technologies as soon as they are available. In that case they could offer a better, cheaper product in forcing any other company to adapt to compete. If Musk is saying his battery will not see anything but incremental improvements, then his company may be left in the dust by others that can incorporate those new technologies. On the other hand, he may be right in which case the electric car could be a bust being too expensive for the average person. I know I can't afford one and I certainly don't want to pay half of the car's sticker price for a replacement battery every three to five years.
 
  • #49
CraigHB said:
but there's plenty of competition.
Where for batteries? There are no other 35 GWh/yr battery plants under construction, funded, or even under serious planning as of some months ago (i.e. a site purchased ...). It might well happen, but it can't happen quickly. It has to be this way. One can't sink several billion dollars into a factory design to produce a product lasting ~ 10 yrs and have it become obsolete in a couple years. If this was commonly the case, the several billion dollars of funding would never materialize.
 
  • #50
CraigHB said:
I know I can't afford one and I certainly don't want to pay half of the car's sticker price for a replacement battery every three to five years.
Even if it is cheaper to run? Simple calculations show that buying a battery every few years + the cost of electricity is pretty similar to the cost an empty fuel tank that must be filled every week. The problem is that you must pay the whole battery in advance. Also, if you have an accident, you lose your «investment».

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

If you agree with the danger and urgency to act about climate change, "I can't afford" is not an option. If you don't, then waiting for the electric car to become a cheaper alternative to ICE will probably be a big deception. If it was easily feasible, it would have been done a long time ago.
 
  • #51
jack action said:
Simple calculations show that buying a battery every few years + the cost of electricity is pretty similar to the cost an empty fuel tank that must be filled every week.

I think people should take some personal responsibility for the state of the environment, but that only works to a point. The system has a lot of inertia and it's hard to make it change course. There's a limit to what I can do personally to initiate change and I still have to live within the system. I do what I can, but that may not be good enough. Like most people I'm not willing to assume hardship for the sake of the environment.

It's reasonable to care about the environment enough to spend more than I would normally. I've not actually worked out the cost of an electric car in the long run. No matter since I can't afford to buy a new car right now regardless of how it's powered. If I ~have~ to buy a car, it will be one with a low initial cost. The idea of a car loan twice the amount is not very attractive. Though sticking it to the evil oil companies would be some compensation. I think my situation probably reflects the average state of peoples' finances. The cost of living has been going up a lot faster than salaries for many years now.

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.
 
  • #52
CraigHB said:
Though sticking it to the evil oil companies would be some compensation

Why are they evil? You just said yourself that you are going to make choices that are bad for the environment for economic reasons. Is what the oil companies do any worse?
 
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  • #53
Would more make sense to keep diversifying the energetic diet of the fleet instead of specializing on a single dish. The hybrid concept should be developed as greener paradigms start taking over. An omnipresent electric grid need not be mutually exclusive with hydrogen or any other green/carbon-neutral fuel. More fail-safe and there will probably be niches for each type. Done progressively in a cost efficient way, it should be possible.
 
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  • #54
In my other thread about the gas trailers, my point was that it is important to find ways to reduce the cost of electric cars, and that encouraging mass adoption would do that. Teasla's new battery is in the news now. Can we project with certainty that in ten years, electrics will be cheaper to operate, and gas cars will cost more? Given that in an honest economy, the entire cost of the Iraq war ought to be paid in gasoline taxes, I'd say this is a good bet.

Vanadium 50 said:
Why are they evil? You just said yourself that you are going to make choices that are bad for the environment for economic reasons. Is what the oil companies do any worse?

They are evil because they suppressed research answers they got in the 1970s, and then tried to discredit others who reached the same conclusions.
 
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  • #55
The "oil companies" is not a monolithic entity secretly controlled in perpetuity by a Dr Evil who emerges periodically from the deep freeze, any more than the environmental movement is a monolith controlled by immortal malthusians who want to wipe out most of the world's human population to save Gaia.
 
  • #57
There are dozens of oil companies in the US alone, I'd guess hundreds world wide, and they are not all run by guys around in the 70s. The scientific world knew about the theory of AGW 40 years ago. The basic theory goes back to at least Arrhenius in 1895. Is this forum the place for overblown and invented bad guy theories sourced with "according to Greenpeace"?
 
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  • #58
CraigHB said:
I think my situation probably reflects the average state of peoples' finances. The cost of living has been going up a lot faster than salaries for many years now.
That's outside the scope of the thread, but please have a look at the actual statistics, because what you believe turns out to not be true:
http://www2.census.gov/programs-sur...series/historical-income-households/h03ar.xls

And yeah, let's cool it with the "oil companies are evil" conspiracy theories please. This isn't the place for them and if you think about them for just a little bit, the conspiracy theories themselves are typically self-contradictory (they suppressed things that were known 40 years ago? and we know because...? [they weren't actually suppressed]).
 
  • #59
russ_watters said:
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No microsoft formats. If it needs to be said, it needs to be readable.
 
  • #60
Algr said:
If it needs to be said, it needs to be readable.

Nearly every spreadsheet software can read that format. I could see your point if only paid Microsoft products could read it but many open and closed source free and paid applications can.

BoB
 

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