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Hydrogen vs. Battery
- Thread starter siry
- Start date
Not participating in the discussion, just adding an observation: One of the few hydrogen stations in Norway just blew up.
Kraftig eksplosjon på hydrogenstasjon i Sandvika - fare for flere eksplosjoner
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Kraftig eksplosjon på hydrogenstasjon i Sandvika - fare for flere eksplosjoner
In English:
Google Translate
mspohr
Well-Known Member
The important thing is that a Tesla was involved! Apparently it was driving by at the time of the explosion and the airbags in the Tesla went off. I'm sure the media will blame Tesla.
Dr. J
Active Member
The myth of the HFC cars will be kept alive by the fossil fuel industry as an alternative to BEVs for as long as they can.
Apart for the mentioned deficiencies, such as low energy efficiency, very expensive re-fueling infrastructure, more complexity in the cars (implies higher maintenance cost), economic disadvantages, there is one more aspect to consider in light of this incident:
The fact, that the rear-seat passengers of HFC cars are literally sitting on powerful bombs!
It is not a matter of 'if' but 'when' an accident / car crash will occur that punctures one of those 10,000psi canisters, causing an explosion that will remind everyone of the Hindenburg. That will be the all too familiar end of this second chapter of hydrogen based transportation in human History.
Apart for the mentioned deficiencies, such as low energy efficiency, very expensive re-fueling infrastructure, more complexity in the cars (implies higher maintenance cost), economic disadvantages, there is one more aspect to consider in light of this incident:
The fact, that the rear-seat passengers of HFC cars are literally sitting on powerful bombs!
It is not a matter of 'if' but 'when' an accident / car crash will occur that punctures one of those 10,000psi canisters, causing an explosion that will remind everyone of the Hindenburg. That will be the all too familiar end of this second chapter of hydrogen based transportation in human History.
nwdiver
Well-Known Member
Well.... I don't know about that... without Oxygen Hydrogen is pretty harmless. The tank itself cannot explode but the hydrogen can leak out and accumulate in the trunk or something. Proper ventilation should prevent it from accumulating to dangerous levels.
Here's an interesting video showing the difference between a H2 fire (100% H2 balloons) and a H2 BOOM (66% H2, 33%O2)
Grid tied solar without storage means when grid goes down, so does solar, probably to isolate the grid while technicians work on it.
Solar + Powerwall(PW) means PW is off grid, i.e. PW2 cannot import from nor export to grid. As u said, this probably is enforced by power company to avoid PW imports at low rates, and exports back at high rates.
The solar in fact can be completely off grid, but most keep the solar grid-tied(e.g. solar capacity not that big, or no battery, or battery not that big, or take advantage of net energy metering NEM).
nwdiver
Well-Known Member
..... utilities would want that.... the reason rates are low is because there's a supply surplus... charging batteries would help. The reason rates are high is there's a deficit... discharging batteries would help.
There is a lot of hear-say about this;
PW is off grid and needs to be charged by solar to be eligible for 30% ITC.
Solar itself can be off or on grid to qualify for 30% ITC.
Powerwall3 should be available soon.
That is the idea of Honda/Toyota/Hyundai and several other countries, apparently they think it is a viable future for them.
Replying to a lot of posts over several days. Sorry for the long post.
If you aren't using solar panels, then you're comparing apples and oranges. The state of the art as far as solar power conversion efficiency goes, is from solar thermal generation stations, which have efficiency around 50%. So even 36% would still be a total joke — 19% approximately doubly so.
So what you have here is an industrial process that releases most of the hydrogen that it produces. Ask yourself this: Given how easy it is to burn hydrogen as fuel, if it were worth the effort, don't you'd think they would be capturing it and producing electricity already? From this, we can infer that the cost of collecting the hydrogen exceeds its value, and that equation will not change with hydrogen cars, because it will still be cheaper to produce new hydrogen with electricity than to capture those waste products. Were that not the case, it would also be worth capturing that hydrogen and turning it into electricity. (Okay, in theory, if it is currently only unprofitable by one or two percent, it might be barely financially viable, but that's noise.)
Besides, 3 million tons of hydrogen isn't much. That's only about 2.7 billion kg. One kg of gas is, I believe, roughly equivalent to a gallon of gas in terms of its ability to move cars, and the U.S. alone used 142.86 billion gallons of gasoline in 2018. Therefore, all the wasted hydrogen in the world would still replace less than 1.9% of U.S. gasoline consumption. Compared with the double-digit efficiency loss resulting from using hydrogen instead of a battery, that bonus 1.9% is lost in the noise. And even if it weren't, you'd still be much better off burning the hydrogen on-site and turning it into electricity.
I assume you mean on top of the one space per vehicle, because otherwise, I'm seriously impressed at your car-stacking charging station.
The fossil fuel industry has a vested interest in keeping everyone hooked. Wherever there is money, there are people excited to take the money and do research with it.
All of this is entirely moot. The limiting factor is the fact that A. the cost of producing the hydrogen cannot realistically ever be less than the cost of producing an equivalent amount of electricity, and B. it would have to be around a third the cost of producing the equivalent amount of electricity to cancel out all the other efficiency losses that occur at every stage along the way when using hydrogen as a fuel source.
There's no way that power grid distribution results in 10% loss, realistically. The average, at least in the U.S., is only 5%. Besides, why would you include that on the EV side and not on the FCV side? Either the AC goes over the grid or it doesn't, and that's independent of whether you're using it to charge a car or produce hydrogen. So I would argue that the efficiency of the FCVs ought to be 5% lower, and the EVs ~5.55% higher (95/90).
Absolutely. Hydrogen might eventually make sense as bulk storage for the grid. It won't be done with fuel cells, though. They're far too expensive to use at scale. Rather, they'll produce hydrogen in bulk — probably thermally with steam reforming, but possibly by electrolysis — and store it at low density (no compression penalty), then burn it to spin turbines.
That said, the reason it probably won't ever make sense even for grid storage is that pumped water energy storage is 70–87% efficient today, and flywheels can achieve up to 85% efficiency today, whereas steam reforming of hydrogen (currently the most efficient approach) is only 70–85% efficient before you factor in the additional losses from converting it back into electricity, which yields only about 45–51% total efficiency today. So it would need to get half again more efficient to compete in today's economy. That is within the realm of possibility, but pretty unlikely (particularly because any efficiency improvements on the turbine side would also likely improve the efficiency of pumped water energy storage).
You mean like the Post-It® notes in the supply closet at work?
No, including hydrogen fuel cells. All fuel-cell-based cars require a battery, because fuel cells can't ramp up quickly enough, and even if we ignore vampire drain, even if we assume that the battery is a Lithium ion pack, it will still be approximately flat from self-discharge in ten years, by which time the fuel cell will have long since kicked in to bring it back up out of the danger zone to avoid hardware damage. But if you consider a NiMH battery like they use in some FCVs, it will be completely dead within two years from self-discharge, so the fuel cell will have charged the pack at least five times, which is an 8 kWh loss, or ~9% total discharge.
And that's only half the story, if the vehicle happens to have the same level of vampire drain that Tesla cars have, it won't even last as long as the battery in a Tesla, thanks to the higher self-discharge of the NiMH batteries.
If you aren't using solar panels, then you're comparing apples and oranges. The state of the art as far as solar power conversion efficiency goes, is from solar thermal generation stations, which have efficiency around 50%. So even 36% would still be a total joke — 19% approximately doubly so.
So what you have here is an industrial process that releases most of the hydrogen that it produces. Ask yourself this: Given how easy it is to burn hydrogen as fuel, if it were worth the effort, don't you'd think they would be capturing it and producing electricity already? From this, we can infer that the cost of collecting the hydrogen exceeds its value, and that equation will not change with hydrogen cars, because it will still be cheaper to produce new hydrogen with electricity than to capture those waste products. Were that not the case, it would also be worth capturing that hydrogen and turning it into electricity. (Okay, in theory, if it is currently only unprofitable by one or two percent, it might be barely financially viable, but that's noise.)
Besides, 3 million tons of hydrogen isn't much. That's only about 2.7 billion kg. One kg of gas is, I believe, roughly equivalent to a gallon of gas in terms of its ability to move cars, and the U.S. alone used 142.86 billion gallons of gasoline in 2018. Therefore, all the wasted hydrogen in the world would still replace less than 1.9% of U.S. gasoline consumption. Compared with the double-digit efficiency loss resulting from using hydrogen instead of a battery, that bonus 1.9% is lost in the noise. And even if it weren't, you'd still be much better off burning the hydrogen on-site and turning it into electricity.
I assume you mean on top of the one space per vehicle, because otherwise, I'm seriously impressed at your car-stacking charging station.
The fossil fuel industry has a vested interest in keeping everyone hooked. Wherever there is money, there are people excited to take the money and do research with it.
All of this is entirely moot. The limiting factor is the fact that A. the cost of producing the hydrogen cannot realistically ever be less than the cost of producing an equivalent amount of electricity, and B. it would have to be around a third the cost of producing the equivalent amount of electricity to cancel out all the other efficiency losses that occur at every stage along the way when using hydrogen as a fuel source.
Probably good to go back to this diagram:
Compression only loses 10% so even if you have a great improvement in compression for storage, it doesn't make much difference in the pathetic overall efficiency of the fuel cell system.
There's no way that power grid distribution results in 10% loss, realistically. The average, at least in the U.S., is only 5%. Besides, why would you include that on the EV side and not on the FCV side? Either the AC goes over the grid or it doesn't, and that's independent of whether you're using it to charge a car or produce hydrogen. So I would argue that the efficiency of the FCVs ought to be 5% lower, and the EVs ~5.55% higher (95/90).
Absolutely. Hydrogen might eventually make sense as bulk storage for the grid. It won't be done with fuel cells, though. They're far too expensive to use at scale. Rather, they'll produce hydrogen in bulk — probably thermally with steam reforming, but possibly by electrolysis — and store it at low density (no compression penalty), then burn it to spin turbines.
That said, the reason it probably won't ever make sense even for grid storage is that pumped water energy storage is 70–87% efficient today, and flywheels can achieve up to 85% efficiency today, whereas steam reforming of hydrogen (currently the most efficient approach) is only 70–85% efficient before you factor in the additional losses from converting it back into electricity, which yields only about 45–51% total efficiency today. So it would need to get half again more efficient to compete in today's economy. That is within the realm of possibility, but pretty unlikely (particularly because any efficiency improvements on the turbine side would also likely improve the efficiency of pumped water energy storage).
You mean like the Post-It® notes in the supply closet at work?
No, including hydrogen fuel cells. All fuel-cell-based cars require a battery, because fuel cells can't ramp up quickly enough, and even if we ignore vampire drain, even if we assume that the battery is a Lithium ion pack, it will still be approximately flat from self-discharge in ten years, by which time the fuel cell will have long since kicked in to bring it back up out of the danger zone to avoid hardware damage. But if you consider a NiMH battery like they use in some FCVs, it will be completely dead within two years from self-discharge, so the fuel cell will have charged the pack at least five times, which is an 8 kWh loss, or ~9% total discharge.
And that's only half the story, if the vehicle happens to have the same level of vampire drain that Tesla cars have, it won't even last as long as the battery in a Tesla, thanks to the higher self-discharge of the NiMH batteries.
In peak rate hours(e.g. today was 100F+ sunny clear afternoon around here) with high demand (e.g. AC), and high supply(e.g. solar at full tilt). The grid is under the most stress at this time. Off grid storage can absorb excess PV outputs and smooth out the load on the grid.
nwdiver
Well-Known Member
.... read that back to yourself slowly.
That means your solar roof does not pump all the excess(e.g, a chunk of 13.5kWh per PW2) back on the grid, instead store it off grid. This reduces the load on the grid in peak hours.
NEL (the supplier of the hydrogen filling station that blew up) has closed down the other two stations in Norway and another 8 across Denmark and other countries. (Not sure if US is affected, though it might be.)
There's currently no place in Norway to fill hydrogen on a private vehicle. Though luckily few are affected, as there are only 160 hydrogen cars total in Norway.
There's currently no place in Norway to fill hydrogen on a private vehicle. Though luckily few are affected, as there are only 160 hydrogen cars total in Norway.
nwdiver
Well-Known Member
During peak hours export is a good thing. Load is demand. Exporting surplus effectively decreases demand. Storage is grid-tied not 'off-grid'.
Oh the Humanity!!
.... too soon?
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