Man with billions invested in electric cars disparages competing technology? I am shocked.
The fact is, you don't need to have a high energy density with hydrogen, as existing gas stations can be used to quick refuel a hydrogen car (with robotic assist, perhaps), without the logistical mess that comes from swapping an extremely heavy, very expensive, potentially user-abused battery with another one. You can even burn hydrogen in an ICE engine, as BMW has demonstrated.
The Honda Clarity FCX, a hydrogen powered car, is the only other car to achieve Type V California ZEV credits besides the Model S. Perhaps that's too much competition for Musk. The range of that car is 240 miles.
If he thought hydrogen was viable, he'd be working on it.
He is one person, and he is not all knowing. He has limited time and potential. He also has a significant ego and financial interest in their current course.
He's a smart guy, but I'm not going to write something off because he isn't into it.
I give Musk a bit more credit than most CEOs, but he has also shown himself to be very capable of playing the spin game in the press recently (the funky math on the 'new finance product', declaring that the NYT backed off its Tesla piece when they in no way did).
Yes, I was hoping the article actually shared some of the research Tesla must undoubtedly have done about the feasibility of fuel cells. Yes, they have limited range, but so do batteries. But while it takes _hours_ to recharge a battery, refueling hydrogen takes a couple of minutes, same as petrol.
All his other arguments about infrastructure and safety apply equally well to petrol cars, and yet here we somehow managed to implement that efficiently. I don't see any inherent reason why we can't do the same for Hydrogen.
And how much energy is lost converting energy to hydrogen? Because there are no native hydrogen energy stores. You're either using electricity to crack water, or you're going to crack natural gas.
Its more efficient to simply use batteries.
EDIT: I'd like to point out, generating hydrogen does make sense if you're using an energy source that is essentially free. Too much hydro and you have to dump the water anyway? Make hydrogen. Too much wind and the transmission operator is shutting down your production? Make hydrogen. Otherwise, it doesn't make sense to use it as an energy transfer medium.
source?
edit: that link doesn't really say that hydrogen is less efficent than batteries, just that it has less energy than the energy content of the original fuel, which is true with charging a battery too because of transmission losses, ect.
Nature? Free hydrogen doesn't really exist on earth; atmospheric hydrogen is something like 1 ppm. There's tons of hydrogen on earth, but it's all in water and hydrocarbons, which you have to split to get to the hydrogen itself.
The Wikipedia article on water splitting notes that "production of hydrogen from water requires large amounts of energy and is uncompetitive with production from coal or natural gas." If you're capturing it as a byproduct of an existing process, then it probably makes sense, but just applying electricity to water to generate hydrogen to burn isn't very economical right now.
I know this is somewhat tongue-in-cheek, but what would the long-term consequences be of importing large quantities of hydrogen from off-planet and then binding it to local oxygen?
I suppose if we had the tech to do that, we might be able to find off-planet oxygen as well...? Except wasn't most of ours produced by plants splitting carbon-dioxide?
So water electrolysis has losses of 50-80%. And then you need to transport it to refueling stations (which could be pretty high). Edit: forgot the obvious, the losses in the actual fuel cell. 40-60%. Yeah that equation doesn't add up.
What losses to we have on the battery end? Transmission line losses (6%), li-ion charge/discharge losses (80-90%), losses due to the fact that the car needs to keep the battery warm/cool depending on outside temperature (pretty high in the winter, regular 120V outlet is not enough to keep the capacity up).
Personally I dismiss hydrogen mostly because I'm frightened by the thought of a bunch of high pressure fire bombs being driven around by drunk people.
All current renewable energy sources have one big flaw. They produce energy when the circumstances are right, not when required. Beacause of this they cause issues in the energy grid.
If we could build water cracking facilities at the right scale with the right characteristics, that could help offset the efficiency/cost issues.
And on the issue of high pressure fire bombs, gas powered cars are pretty common here in Europe and those things are pretty safe. There are numerous safety features, not to mention that gas tanks are pretty tough vessels.
Edit: On the topic of fire bombs. I have today learned that one would not want Hydrogen tank in his vehicle.
>Edit: On the topic of fire bombs. I have today learned that one would not want Hydrogen tank in his vehicle.
Everyone comes to this conclusion when you realize how deadly compressed hydrogen is compared to liquid petroleum. Nothing like being burned by fire you can't see.
Given how quickly an explosive shock wave travels through hydrogen, I doubt anyone near the car would be alive long enough to even register a mild temperature increase when the tank blows up.
And how much energy is lost charging batteries? Because there are no native sources for charged Tesla battery packs. You're either using electricity to charge them at your house (with 60% lost in transmission) or charging them closer to the power plant.
It's more efficient to simply use hydrogen.
I don't understand why anyone would be convinced by arguments like this that don't include numbers, when you can make the argument sound equally valid on either side of the debate.
> using electricity to charge them at your house (with 60% lost in transmission)
The overall losses in Germany are 7%. [1]
> It's more efficient to simply use hydrogen.
Only if you fake your numbers by an order of magnitude, see above.
> I don't understand why anyone would be convinced by arguments like this that don't include numbers.
Still better than your astroturf numbers. If hydrogen is better, so be it. However, the Tesla S can go 450km with one charge today and it can be charged everywhere.
An electric car is the nightmare of traditional car manufacturers: an electric motor costs nothing and lasts unlimited kilometers. You need no engine oil change, the brakes last a lot longer and cars will easily last 1.000.000 miles / kilometers and a lot more with little maintenance. You do need to change the battery but this is not money for the car manufacturer.
So there are two huge industries for which e-cars are a nightmare: petrol and classic car manufacturers.
Disclosure: I drive an MiEV an it works amazingly well.
If we're talking about the US, we have tons of open space. Really, tons. Americans don't appreciate just how much open space is in this country. If it's really a concern, it can be done with water towers rather than a conveniently-placed hill.
As for transport, that's what a power grid is for. Transporting hydrogen loses more efficiency than transmission losses.
Batteries are way ahead on every objective measure, and getting better every year.
Um have you seen a pumped storage power plants they are major civil engineering constructions.
You could probably add a small hydrogen storage facility to every wind farm in the UK for less than the cost of the public inquiry into a new pumped storage scheme.
That's not the same thing. In a standard hydroelectric dam, you need an existing river to create electricity.
The goal of pumped storage isn't to create new electricity, but to store large amounts of unused baseload power. This can be done with a standard hydroelectric dam by pumping the water back up into the lake behind the dam, but it can also be an entirely artificial reservoir.
yes but the number of places that are suitable are limited and it might be politicaly sensitive eg flooding Wales and Scotland to provide power for the English.
And farmers might object to you taking the water they use for irrigation
There are three pressing concerns for hydrogen fuel cells, which can be added up to "bullshit". First, energy density. I can't speak to that in detail, but the range problem is serious. Then again, the range problem seemed insurmountable for electric cars until Tesla got within spitting distance.
Second, platinum. Traditional hydrogen cells require some platinum in the catalyst, which is fine at lab scales, but unviable at industrial scale. There have been advances in alternative catalysts recently, but until fuel cells can be built without rare and exotic raw materials, they're just a toy.
Third, power source. Hydrogen comes from cracking water, which requires energy. It's just a storage medium for energy provided during the cracking process. What's the end-to-end thermal efficiency of that process? And where does the power come from? Of course, this problem applies 100% to battery-powered cars as well.
Oil is a net positive on the energy, even with the energy cost to refine it. Generating hydrogen from water is a net negative on the energy, guaranteed, by thermodynamics.
Unless we start stealing it from an extra-planetary source, it is best to think of hydrogen as a battery, not a fuel.
Or if they use algae or a microbial process to produce hydrogen instead, or concentrated solar to dissociate water into hydrogen and oxygen? Electrolysis isn't the only option.
Oil is not a net positive on the energy; gasoline consumes more in electricity during the refining process than it contains; it's just in a much more useful form.
That is a fascinating claim. I've just spent twenty minutes or so trying to track down the origin and veracity of it.
As near as I can tell, that is a corruption of the claim "you can drive an electric car further on the electricity which goes into refining a gallon of gas than you can a car on the same gallon of gas".
Specifically, the numbers I saw people quoting were that it took between 3 and 7.5 kWh of electricity to refine a gallon of gas, and that an electric vehicle could drive 30-50 miles on that amount of electricity.
However, a gallon of gasoline contains far more than 7.5 kWh: approximately 37.8 kWh. So gasoline is still a net positive on energy, even after refining.
Thanks for saving me the trouble of tracking down sources.
The claim was inartfully stated at best. However, it all ends up going back to your definition of "net positive". I read "net positive" as getting more out than you put in during the refining process. Neither gasoline nor hydrogen from water is a net positive by this basis.
If you extend the "net positive" test to the extraction and refining process, then you have to include the process to make the electricity for hydrogen-from-water or it's not a fair comparison. I can't dig up electricity. In this case both processes are net positives if the comparison is even.
First, to be honest, I don't trust the initial claim. I couldn't find a source for the 3.5 to 7 kWh figure, and their are a lot of ways it could be wrong or misleading. Firstly, you don't refine gasoline in a vacuum; when you refine a barrel of oil, you get roughly 45 gallons of refined petroleum products, including about 19 gallons of gasoline. Are they assigning the full cost to the gasoline, dividing it by volume, or by energy cost? And 3.5 vs 7.5 is a full factor of two. What is the average cost?
Even taking the energy cost as gospel, it still tells you a heckuva lot more about the vehicles than the fuel. ICEs peak at about 30% efficiency, so you ought to be able to apply a solid 12 kWh from a gallon of gas to making cars go. If the fifty miles you can push a particular electric car on 7.5 kWh is more than your typical car, that's hardly the fuel's fault. And indeed: the current record for fuel efficiency is 209 mpg.
So it's duplicitous to say that electricity is more efficient for running cars than gasoline, or claim gasoline is somehow energy negative. We get so much energy from gasoline we can be extraordinarily wasteful in how we use it.
Even liquid hydrogen doesn't come close to the volumetric energy density that seems like it'd be a solution for transportation. And the more compressed or cold you get it has a lot of attendant problems in terms of expansion effects of the gas, or the energy required to compress it.
The permeability of hydrogen in containers, especially at high pressure, is also a real concern. Hydrogen escapes through container walls, and has bad (embrittling, usually) effects on them. A brittle 10,000psi H2 tank on board a car is something you really do not want.
It seems to me the most feasible path to fuel cell power is to use non-pure-hydrogen fuels.
While everyone is talking up hydrogen as a clean alternative. Currently, 90% of hydrogen is refined using fossil fuels. Even if you account for hypothetical/nonexistent future technologies, the majority of hydrogen for the foreseeable future is coming from fossil fuels. Hydrogen is truly, "Bullshit". If it launches nationwide it be because gas companies are behind the push, and they will only do it once their gasoline revenue starts to dwindle.
Depends where you are and your definition of 'green'. In Ontario, right now we're running on:
- 57% nuclear
- 25% hydro
- 14% gas
- 3% wind
- 1% coal
- <1% other (mostly natural gas, apparently)
If you consider nuclear, hydroelectric and wind to be 'green' (in the sense that they don't produce CO2), then we're running on 85% green power in Ontario right now.
I don't understand why there is so much controversy and disagreement surrounding this question. Electric cars are a requirement for a sustainable energy economy. Where the energy comes from, doesn't really matter in the short term as long as it comes from renewable or nuclear energy in the long term.
Regardless, people claiming that electric cars aren't green because the electrical power is often produced from fossil sources, conveniently forget that a lot of fossil fuels are spent producing petroleum fuels. You don't just stick a straw into the ground and have gasoline pour automatically into every gas station in the world.
First, you have to have survey teams (often offshore) find oil. Then you have to build the production infrastructure to get it out of the ground. Then you have to add water injection and other tricks to get it out of the ground. Then you have to transport it to a refinery. Then you have to refine it. Then you have to transport it to gas stations. So it's not as easy as some of the naysayers claim.
The hydrogen from fossil fuels isn't used for energy directly, but rather for making nitrate fertilizer. Hydrogen energy storage would probably come from electrolyzing water.
Not that this is likely to work, anyway. There's many reasons to believe that hydrogen isn't going to catch up to batteries for this purpose. It's thermodynamically impossible for it to function as a primary energy source unless we can find an easy source of elemental hydrogen. Musk is biased, but he probably had good reasons for taking Tesla in the direction he did.
There are many technical problems with hydrogen: metal embrittlement, it leaks even through solid substances, etc. They're not insurmountable, but they make hydrogen not that competitive with electric. Elon is not a fan of H2 for rockets either for those very same reasons-- embrittlement, leakage, cost of storage and handling. Guy is flat out anti-hydrogen, man.
That and once you have hydrogen it's not that hard to go from there to CH4-- methane. Once you're there, natural gas fuel cells and vehicles make more sense as methane is infinitely easier to handle and already has a ton of deployed infrastructure.
They're already doing this in Germany-- making CH4 from H2O and CO2 with surplus renewable energy and then feeding it into the natural gas grid.
Pretty much this. Handling pure hydrogen is a suckers game in terms of complexity. The real problem is we don't have a compact, low temperature direct methane/direct methanol/ethanol fuel cell yet.
IMHO hydrogen fuel cell technology is more practical. No charging time means that you can travel any range without delays as long as you have hydrogen fuel stations on your way. That kind of technology gives you more freedom I guess. You feel less limited by your vehicle.
And as far as I know charging li-ion batteries is still very slow, they will go flat at some point, faster you are charging them faster they become flat and they are very heavy.
Charging time is overblown. You can charge a modern battery to 80% in about 5 minutes. That's about how long it takes to fill my car with gas at the moment.
You're not going to be refueling a hydrogen fueled car that quick - it's a volatile, extremely high pressure, extremely cold gas. The safety considerations are substantial.
Ok, what about durability of batteries compared with durability of fuel cell? I'm just curious because I think that batteries are less durable right now than fuel cells.
DOE targets 5k hrs of operation for fuel cells used in transportation. I haven't been able to find an hours of operation for batteries. Wikipedia gins up some numbers to claim 10 to 20 years life expectancy. On the whole it seems batteries are in the lead at this point, but both are near the expected baseline for automobiles.
At what amperage and voltage and how much did it cost to upgrade the charging station connection to the grid.
And how do you cool the battery during such a fast charge? what % of the energy is lost in heat from the chemical reaction - even Tesla has to obey the laws of thermo dynamics.
Thinking about it from a thermofluids angle You could I suppose have a complex system of heat exchangers built in to the the battery pack and hook the car up to a water connection and flush chilled water (or better some non conductive fluid) through whilst charging but water and high voltage and amps are not the best of friends.
Tesla's supercharging stations charge at 135kW 400V DC, recharging >50% of a 85kWH battery in 30 minutes. The power is delivered from a large (>300kWH) battery pack installed in the charging station, which is continously trickle-charged from the grid. There will also be swap stations implemented, swapping out the entire 85kWH battery pack in 2 minutes.
This is largely a solved problem, both from the sides of technology and deployment. It's just that public perception hasn't caught up yet. Give it 5 years and just about everyone will want one of these cars. For everyday use you won't even need the quick-charge capability.
> Give it 5 years and just about everyone will want one of these cars.
They sold a batch of MiEV / IOn for $15.000 here and so far everybody is very enthusiastic about them. I think 5 years is a tad optimistic but I give it less then 10 years.
Ever try to move a large quantity of compressed gas from one place to another in a hurry? It's never as simple as "no charging time."
In my opinion, any alternative-fuel technology that doesn't involve swappable power modules -- whether they're batteries, fuel cells, fusion reactors, or whatever -- is bullshit. Tesla has at least taken some steps in the right direction.
Its not that hydrogen is unrealistic. Hydrogen cars currently exist. The problem is that mass producing hydrogen is just as problematic as mass producing gasoline.
As an interesting aside, the leading use for hydrogen today, with over 50% of all hydrogen used, is in oil refining. That hydrogen (along with almost all the balance) comes from steam-reformed natural gas.
It's also true that more electricity is consumed refining gasoline (without even figuring the oil itself's energy) than in producing hydrogen (per gge). The important distinction is that gasoline is an outstanding motor fuel, able to deliver 3000x the volumetric energy density of hydrogen gas, 6x the volumetric energy density of compressed hydrogen and 3x the volumetric energy density of liquefied hydrogen.
Those numbers get even more stark when you add in tank weights.
Musk's Youtube video demonstrates a battery changeout faster than a gasoline fillup (BTW, ever filled up a tank with H2? It's not as fast as gasoline per gge; not even close).
I share the BS opinion on hydrogen fuel cells. Hydrogen tanks cost too much, weigh too much and better alternatives exist.
Interesting comment. I really like Elon but I think he's a bit off here. My reasoning is that fuel is fuel. Basically you get the energy out of gasoline through an exothermic reaction with oxygen, you get the energy out of Lithium Phosphate by the electron exchange reactions with the cathode. Fuel cells can be the middle road, liquid fuel into electron exchange through catalysts.
The "issue" with fuel cells is that you cannot easily make fuel at home. I get that, if we're one end use energy form (electricity) then we can optimize the infrastructure to carry and deliver that efficiently. But arguments about energy density are silly. There is way more energy in a gallon of gas than you can put into an equal volume or weight of battery. That is why you can use it as a fuel at 20% efficiency and still have a viable business model.
So what is 'bullshit' here? Is it that people won't create the infrastructure to make fuel cell friendly fuels? Is it that a parallel fuel structure can't compete with the existing gas distribution infrastructure? So I don't buy the idea that fuel cells as a power mechanism are non-viable but could see and argument that a car eco system based on them is unlikely.
It kind of bothers me when people talk about fuel cell vehicles as being "emissions free". Producing the Hydrogen required to run a fuel cell requires either electrolysis of water, or extracting it from natural gas. That's really energy intensive. Either the emissions come out your tailpipe or go out a smokestack. Pick your poison.
There are other interesting fuel cell technologies that use liquids, like methanol, instead of Hydrogen as a fuel source, but even Methanol requires energy to be produced.
Has anyone looked into running the fuel cell in reverse to recharge it? I remember seeing a demo at a fair where it was a sealed fuel cell and it could go from h2 02 to water and then run it in reverse to recreate the o2 and h2.
If that's feasible it could simply be a new type of battery, no?
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[ 7.1 ms ] story [ 164 ms ] threadThe fact is, you don't need to have a high energy density with hydrogen, as existing gas stations can be used to quick refuel a hydrogen car (with robotic assist, perhaps), without the logistical mess that comes from swapping an extremely heavy, very expensive, potentially user-abused battery with another one. You can even burn hydrogen in an ICE engine, as BMW has demonstrated.
The Honda Clarity FCX, a hydrogen powered car, is the only other car to achieve Type V California ZEV credits besides the Model S. Perhaps that's too much competition for Musk. The range of that car is 240 miles.
He is one person, and he is not all knowing. He has limited time and potential. He also has a significant ego and financial interest in their current course.
He's a smart guy, but I'm not going to write something off because he isn't into it.
All his other arguments about infrastructure and safety apply equally well to petrol cars, and yet here we somehow managed to implement that efficiently. I don't see any inherent reason why we can't do the same for Hydrogen.
[1] http://www.teslamotors.com/supercharger
Its more efficient to simply use batteries.
EDIT: I'd like to point out, generating hydrogen does make sense if you're using an energy source that is essentially free. Too much hydro and you have to dump the water anyway? Make hydrogen. Too much wind and the transmission operator is shutting down your production? Make hydrogen. Otherwise, it doesn't make sense to use it as an energy transfer medium.
http://en.wikipedia.org/wiki/Hydrogen_economy#Current_produc...
The Wikipedia article on water splitting notes that "production of hydrogen from water requires large amounts of energy and is uncompetitive with production from coal or natural gas." If you're capturing it as a byproduct of an existing process, then it probably makes sense, but just applying electricity to water to generate hydrogen to burn isn't very economical right now.
I suppose if we had the tech to do that, we might be able to find off-planet oxygen as well...? Except wasn't most of ours produced by plants splitting carbon-dioxide?
What losses to we have on the battery end? Transmission line losses (6%), li-ion charge/discharge losses (80-90%), losses due to the fact that the car needs to keep the battery warm/cool depending on outside temperature (pretty high in the winter, regular 120V outlet is not enough to keep the capacity up).
Personally I dismiss hydrogen mostly because I'm frightened by the thought of a bunch of high pressure fire bombs being driven around by drunk people.
All current renewable energy sources have one big flaw. They produce energy when the circumstances are right, not when required. Beacause of this they cause issues in the energy grid.
If we could build water cracking facilities at the right scale with the right characteristics, that could help offset the efficiency/cost issues.
And on the issue of high pressure fire bombs, gas powered cars are pretty common here in Europe and those things are pretty safe. There are numerous safety features, not to mention that gas tanks are pretty tough vessels.
Edit: On the topic of fire bombs. I have today learned that one would not want Hydrogen tank in his vehicle.
Everyone comes to this conclusion when you realize how deadly compressed hydrogen is compared to liquid petroleum. Nothing like being burned by fire you can't see.
It's more efficient to simply use hydrogen.
I don't understand why anyone would be convinced by arguments like this that don't include numbers, when you can make the argument sound equally valid on either side of the debate.
The overall losses in Germany are 7%. [1]
> It's more efficient to simply use hydrogen.
Only if you fake your numbers by an order of magnitude, see above.
> I don't understand why anyone would be convinced by arguments like this that don't include numbers.
Still better than your astroturf numbers. If hydrogen is better, so be it. However, the Tesla S can go 450km with one charge today and it can be charged everywhere.
An electric car is the nightmare of traditional car manufacturers: an electric motor costs nothing and lasts unlimited kilometers. You need no engine oil change, the brakes last a lot longer and cars will easily last 1.000.000 miles / kilometers and a lot more with little maintenance. You do need to change the battery but this is not money for the car manufacturer.
So there are two huge industries for which e-cars are a nightmare: petrol and classic car manufacturers.
Disclosure: I drive an MiEV an it works amazingly well.
[1] http://de.wikipedia.org/wiki/%C3%9Cbertragungsverlust (german)
The ability to use effectively the same engines and plant is a big plus for hydrogen.
http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
As for transport, that's what a power grid is for. Transporting hydrogen loses more efficiency than transmission losses.
Batteries are way ahead on every objective measure, and getting better every year.
You could probably add a small hydrogen storage facility to every wind farm in the UK for less than the cost of the public inquiry into a new pumped storage scheme.
See the Hydro section of Sustainable Energy - without the hot air by David JC MacKay:
http://www.withouthotair.com/c8/page_55.shtml
Even though the land mass of the US is larger than the UK, it's hard to see hydro being more than MacKay's 2kW per day per person...
That's two 40W light bulbs left on all day.
The goal of pumped storage isn't to create new electricity, but to store large amounts of unused baseload power. This can be done with a standard hydroelectric dam by pumping the water back up into the lake behind the dam, but it can also be an entirely artificial reservoir.
And farmers might object to you taking the water they use for irrigation
Second, platinum. Traditional hydrogen cells require some platinum in the catalyst, which is fine at lab scales, but unviable at industrial scale. There have been advances in alternative catalysts recently, but until fuel cells can be built without rare and exotic raw materials, they're just a toy.
Third, power source. Hydrogen comes from cracking water, which requires energy. It's just a storage medium for energy provided during the cracking process. What's the end-to-end thermal efficiency of that process? And where does the power come from? Of course, this problem applies 100% to battery-powered cars as well.
Unless we start stealing it from an extra-planetary source, it is best to think of hydrogen as a battery, not a fuel.
As near as I can tell, that is a corruption of the claim "you can drive an electric car further on the electricity which goes into refining a gallon of gas than you can a car on the same gallon of gas".
Specifically, the numbers I saw people quoting were that it took between 3 and 7.5 kWh of electricity to refine a gallon of gas, and that an electric vehicle could drive 30-50 miles on that amount of electricity.
However, a gallon of gasoline contains far more than 7.5 kWh: approximately 37.8 kWh. So gasoline is still a net positive on energy, even after refining.
The claim was inartfully stated at best. However, it all ends up going back to your definition of "net positive". I read "net positive" as getting more out than you put in during the refining process. Neither gasoline nor hydrogen from water is a net positive by this basis.
If you extend the "net positive" test to the extraction and refining process, then you have to include the process to make the electricity for hydrogen-from-water or it's not a fair comparison. I can't dig up electricity. In this case both processes are net positives if the comparison is even.
First, to be honest, I don't trust the initial claim. I couldn't find a source for the 3.5 to 7 kWh figure, and their are a lot of ways it could be wrong or misleading. Firstly, you don't refine gasoline in a vacuum; when you refine a barrel of oil, you get roughly 45 gallons of refined petroleum products, including about 19 gallons of gasoline. Are they assigning the full cost to the gasoline, dividing it by volume, or by energy cost? And 3.5 vs 7.5 is a full factor of two. What is the average cost?
Even taking the energy cost as gospel, it still tells you a heckuva lot more about the vehicles than the fuel. ICEs peak at about 30% efficiency, so you ought to be able to apply a solid 12 kWh from a gallon of gas to making cars go. If the fifty miles you can push a particular electric car on 7.5 kWh is more than your typical car, that's hardly the fuel's fault. And indeed: the current record for fuel efficiency is 209 mpg.
So it's duplicitous to say that electricity is more efficient for running cars than gasoline, or claim gasoline is somehow energy negative. We get so much energy from gasoline we can be extraordinarily wasteful in how we use it.
Even liquid hydrogen doesn't come close to the volumetric energy density that seems like it'd be a solution for transportation. And the more compressed or cold you get it has a lot of attendant problems in terms of expansion effects of the gas, or the energy required to compress it.
The permeability of hydrogen in containers, especially at high pressure, is also a real concern. Hydrogen escapes through container walls, and has bad (embrittling, usually) effects on them. A brittle 10,000psi H2 tank on board a car is something you really do not want.
It seems to me the most feasible path to fuel cell power is to use non-pure-hydrogen fuels.
- 57% nuclear
- 25% hydro
- 14% gas
- 3% wind
- 1% coal
- <1% other (mostly natural gas, apparently)
If you consider nuclear, hydroelectric and wind to be 'green' (in the sense that they don't produce CO2), then we're running on 85% green power in Ontario right now.
Source: http://media.cns-snc.ca/ontarioelectricity/ontarioelectricit...
Regardless, people claiming that electric cars aren't green because the electrical power is often produced from fossil sources, conveniently forget that a lot of fossil fuels are spent producing petroleum fuels. You don't just stick a straw into the ground and have gasoline pour automatically into every gas station in the world.
First, you have to have survey teams (often offshore) find oil. Then you have to build the production infrastructure to get it out of the ground. Then you have to add water injection and other tricks to get it out of the ground. Then you have to transport it to a refinery. Then you have to refine it. Then you have to transport it to gas stations. So it's not as easy as some of the naysayers claim.
Not that this is likely to work, anyway. There's many reasons to believe that hydrogen isn't going to catch up to batteries for this purpose. It's thermodynamically impossible for it to function as a primary energy source unless we can find an easy source of elemental hydrogen. Musk is biased, but he probably had good reasons for taking Tesla in the direction he did.
That and once you have hydrogen it's not that hard to go from there to CH4-- methane. Once you're there, natural gas fuel cells and vehicles make more sense as methane is infinitely easier to handle and already has a ton of deployed infrastructure.
They're already doing this in Germany-- making CH4 from H2O and CO2 with surplus renewable energy and then feeding it into the natural gas grid.
And as far as I know charging li-ion batteries is still very slow, they will go flat at some point, faster you are charging them faster they become flat and they are very heavy.
You're not going to be refueling a hydrogen fueled car that quick - it's a volatile, extremely high pressure, extremely cold gas. The safety considerations are substantial.
DOE targets 5k hrs of operation for fuel cells used in transportation. I haven't been able to find an hours of operation for batteries. Wikipedia gins up some numbers to claim 10 to 20 years life expectancy. On the whole it seems batteries are in the lead at this point, but both are near the expected baseline for automobiles.
http://en.wikipedia.org/wiki/Electric_vehicle_battery
And how do you cool the battery during such a fast charge? what % of the energy is lost in heat from the chemical reaction - even Tesla has to obey the laws of thermo dynamics.
Thinking about it from a thermofluids angle You could I suppose have a complex system of heat exchangers built in to the the battery pack and hook the car up to a water connection and flush chilled water (or better some non conductive fluid) through whilst charging but water and high voltage and amps are not the best of friends.
Now where did i put my steam tables :-)
This is largely a solved problem, both from the sides of technology and deployment. It's just that public perception hasn't caught up yet. Give it 5 years and just about everyone will want one of these cars. For everyday use you won't even need the quick-charge capability.
They sold a batch of MiEV / IOn for $15.000 here and so far everybody is very enthusiastic about them. I think 5 years is a tad optimistic but I give it less then 10 years.
In my opinion, any alternative-fuel technology that doesn't involve swappable power modules -- whether they're batteries, fuel cells, fusion reactors, or whatever -- is bullshit. Tesla has at least taken some steps in the right direction.
It's also true that more electricity is consumed refining gasoline (without even figuring the oil itself's energy) than in producing hydrogen (per gge). The important distinction is that gasoline is an outstanding motor fuel, able to deliver 3000x the volumetric energy density of hydrogen gas, 6x the volumetric energy density of compressed hydrogen and 3x the volumetric energy density of liquefied hydrogen.
Those numbers get even more stark when you add in tank weights.
Musk's Youtube video demonstrates a battery changeout faster than a gasoline fillup (BTW, ever filled up a tank with H2? It's not as fast as gasoline per gge; not even close).
I share the BS opinion on hydrogen fuel cells. Hydrogen tanks cost too much, weigh too much and better alternatives exist.
The "issue" with fuel cells is that you cannot easily make fuel at home. I get that, if we're one end use energy form (electricity) then we can optimize the infrastructure to carry and deliver that efficiently. But arguments about energy density are silly. There is way more energy in a gallon of gas than you can put into an equal volume or weight of battery. That is why you can use it as a fuel at 20% efficiency and still have a viable business model.
So what is 'bullshit' here? Is it that people won't create the infrastructure to make fuel cell friendly fuels? Is it that a parallel fuel structure can't compete with the existing gas distribution infrastructure? So I don't buy the idea that fuel cells as a power mechanism are non-viable but could see and argument that a car eco system based on them is unlikely.
There are other interesting fuel cell technologies that use liquids, like methanol, instead of Hydrogen as a fuel source, but even Methanol requires energy to be produced.
https://www.google.ca/finance?chdnp=1&chdd=1&chds=1&chdv=1&c...
Obama cut funding for fuel cell research a few years ago:
http://www.treehugger.com/corporate-responsibility/obama-to-...
If that's feasible it could simply be a new type of battery, no?