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Hydrogen vs. Battery
- Thread starter siry
- Start date
Not sure which one you are referencing here. Possibly this Crescent Dunes Solar Energy Project - Wikipedia
Solar panels that heat water are in the 90%+ range.
Photovoltaics are at 20%.
mspohr
Well-Known Member
When your fuel (sun) is free of cost and has no toxic byproducts, efficiency in operation is irrelevant.
But again, if you're using steam reforming to produce the Hydrogen, you may as well store the Methane instead and avoid the conversion step entirely.
JRP3
Hyperactive Member
At 10,000 PSI nothing is harmless.
mspohr
Well-Known Member
Energy for electrolysis isn't free.That is what HFC fans say about electrolysis!
Wow I never thought there would be so much discussion about Hindenburg Fuel Cells in 2019.
The 1900's called, and they want their century back.
The 1900's called, and they want their century back.
So if I use solar energy for EV charging, it is free of cost. But when I use it for running the electrolyzer, it isn't free.
mspohr
Well-Known Member
I don't know if you're being deliberately obtuse or just plain clueless.
I'll try to explain it one last time for those slow on the uptake.
Electricity has a cost to produce whether it's from the sun, NG, wind, etc. This cost depends on the cost of the equipment (amortized) and the fuel. In the case of sun and wind, the fuel is free so you only have the amortized cost of the equipment. Whether you use the electricity for EV charging directly or to create Hindenberg gas, it still has a cost. The price you pay for the electricity depends on a lot of factors (time of day, transmission cost, etc) and can be positive or negative but the electricity still has a cost. (For the exceptionally slow, please note the difference between cost and price.)
Yes. Hydrogen cars use 3-5 times more energy than BEVs when running on hydrogen produced by electrolysis. So, if the cost of solar is say 10 cents/kWh, and a car does 4 miles per kWh, that's 2.5 cents/mile for BEV and 7.5-12.5 cents/mile for FCV. And then you can add the capital costs for hydrogen electrolysis equipment.
Actually, I was way off on that one. I skimmed an article to try to find that number, and missed some critical details. That was the conversion efficiency to heat, not to power. From there, you take additional hits, so the best current designs are only about 30% efficient end-to-end.
That's still almost twice the best current direct hydrogen splitting efficiency, though. And if I read that link about the direct splitting, they think that 23% is the best theoretically possible conversion percentage achievable by refining their current approach, so if they're right, then that's just not going to fly, barring some revolutionary new approach.
It's also worth noting, any direct hydrogen splitting would have to start with collecting the solar energy, with the losses involved there, and any improvements to that aspect of hydrogen splitting purposes would also improve power generation.
nwdiver
Well-Known Member
Solar panel efficiency is ~worthless for anything other than understanding roughly how much they can improve within the bounds of physics. Or maybe comparing one PV solar panel to another. Or spreading FUD... people like to use it to spread FUD.
Here's an example; You can have 10% of what's in Box A or 20% of what's in Box B.... choose your box. See how XX% doesn't really tell you anything?
Funny... you never hear about the efficiency of wind turbines... because it's an equally nonsensical number. Who cares how much wind energy escapes from a 2MW turbine if it's producing 2MW for $0.02/kWh? They're ~13% efficient but unlike with FCs... with wind and solar the lost energy costs ~nothing. You didn't pay for any of the wind or photons.
It's $/kWh that matters. Turns out that using PV to make electricity is very cheap and using heat from solar to make electricity is very expensive. To the point that it's usually cheaper to install PV on your roof and use a heat pump to heat your water instead of just heating your water directly from solar.
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Johan
Ex got M3 in the divorce, waiting for EU Model Y!
And the cost to clean up the mess that occurs when the stations blow up!
True, I would guess the insurance cost for a hydrogen filling station is significant. Not only is the station itself quite expensive and not entirely unlikely to get destroyed in an explosion over it's lifetime, but you have to factor in the potential costs of blowing out windows in a radius of a mile or so. Plus all the civil suits and what not.
I know the station in Sandvika cost something like $3 million. Gone in an instant.
Watts_Up
Well-Known Member
I remember reading about an hydrogen ban for vehicles in New York from using
the Lincoln Tunnel and the lower level of the George Washington bridge.
But at least, Hydrogen is lighter than air, so there is less limitations than CNG-powered vehicles for using underground parkings.
the Lincoln Tunnel and the lower level of the George Washington bridge.
But at least, Hydrogen is lighter than air, so there is less limitations than CNG-powered vehicles for using underground parkings.
mspohr
Well-Known Member
Fire sale on Toyota Mirai
Toyota Mirai gets deepest discount yet—amid hydrogen shortage
The two modest fuel-cell models you can currently purchase (versus lease) both carry luxury-vehicle prices: a base $59,430 for the 2019 Toyota Mirai and a base $59,345 for the eco-focused Hyundai Nexo Blue. Trade-in or resale value remains an unknown. And at the last time we filled with hydrogen, last October, it cost $17.49 per kilogram—potentially up to a $75 fill for the 312-mile Mirai or a $110 fill for the 380-mile Nexo B
CarsDirect crunched the numbers and found that for the savings (for a narrow subset of shoppers, admittedly) could add up to more than $42,000.
Toyota Mirai gets deepest discount yet—amid hydrogen shortage
The two modest fuel-cell models you can currently purchase (versus lease) both carry luxury-vehicle prices: a base $59,430 for the 2019 Toyota Mirai and a base $59,345 for the eco-focused Hyundai Nexo Blue. Trade-in or resale value remains an unknown. And at the last time we filled with hydrogen, last October, it cost $17.49 per kilogram—potentially up to a $75 fill for the 312-mile Mirai or a $110 fill for the 380-mile Nexo B
CarsDirect crunched the numbers and found that for the savings (for a narrow subset of shoppers, admittedly) could add up to more than $42,000.
The article said the sales price is less than $40k after incentives, that's still not as generous as $10k all-in for those 3-year leases with 20k miles/year, free fuel, free 21-day rentals, free tolling to closest refilling station while inside CA, and free loaners when the refilling stations blow up/out of fuel!
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