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Why did we abandon hydrogen cars so quickly?

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I have a friend who does Solar installs that did it for me. The largest cost was the wire. Roughly $4-5/ft. The breaker was around $30. Another $40 for wiring box and receptacle. The other big hit was the charger itself at $600.

It's why I held off for so long to install. I could have made 120v work for the second car (about 12-13 hours), but there's only one circuit available close enough, so I couldn't charge both cars at once.
 
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For the sake of clarity, this is called 230v split-phase electric service, which is two hots that are 180° out of phase where the difference between the two hots has a RMS voltage of ~230v which is very different than multi-phase service at 208v+ which is RMS voltage relative to neutral, not between the hots. This is more than 115v alone can provide, but it's not the same as having two phases with a common neutral at ~230v which has far more carrying capacity.

The main differences is that split-phase still only uses two conductors like regular 115v service and doesn't use a common neutral.
yeah it could make a difference for certain application when sinewave gets picky, but for charging a car, i didn't think it mattered. esp. in the manner it was addressed; service to residences.

but thanks for the clarification. :)
 
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I wonder if the option to use more than one 110V circuit in a house will one day be practical.
You get a solar / wind generator & power up your grid...but make those batteries hold 400V or 800V in series. & then all you need is DC-DC converter for direct filling up of an electric vehicle. :peace:

Unless you want to move to Europe, where we do have one phase ~230V or triple-phase ~380V. :cool:
 
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That is what they said 10 years ago, for Electric cars.

Look at the momentums going on today. :cool:


The transition to electric cars didn't happen overnight - the seeds were started around 2005 by early Lion hopefuls.

back in 2010 , the Nissan Leaf was the fist serious contender to ignite the market ...and it still took 5 yeas to top 50k cars /year.
The Bolt and Model 3 had a ready-made market for a third generation blitz

There have been Flying Wing Passenger Airplane pitches about every decade from one of the major aircraft makers (it never gathered steam).

The problem isn't the technology (already proven in the NASA Boeing tests) , but having to redesign the entire airport departure area (and the passenger's to accept the concept of windowless "cattle cars for humans" in the year 2021,) makes this an impossible sell anytime soon! There's also concernes with being able to effectively load the Cargo version (many runways need improvements to access the strange layout)


By the time all these other issues are sorted, the jet fuel will have already transitioned to carbon-neutral decades prior (so why do we need hydrogen on aircraft?)

Blended-wing aircraft will happen when they happen (eventually), but the transition to electric vehicles was foretold since the Prius.
Toyota developed nimh car battery market out of existingconsumer products , then enjoying that SMASHING SUCCESS left the market open for others to handle the lion transition.

You can use the consumer market as yoiur ideas for your next large-scale higher-density battery, There is no such "easy-mode" for commercial flying-wings
 
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Aquinus

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Blended-wing aircraft will happen when they happen (eventually), but the transition to electric vehicles was foretold since the Prius. Toyota developed nimh car battery market out of existingconsumer products , then enjoying that SMASHING SUCCESS left the market open for others to handle the lion transition.
The Prius is efficient because of the engine, not the hybrid system believe it or not. The hybrid system is to make up for the power loss from running a modified atkinson cycle because partial power of a small engine isn't enough. The gas mileage comes from how the engine has a higher effective expansion ratio versus compression because the intake valve is kept open through part of the compression stroke. This is why the Prius engines can get away with an effective expansion ratio of 14:1 which is higher than most gasoline vehicles which is where the higher thermal efficiency comes from. The prius is not the only vehicle that does this and not all of them have the hybrid system, such as the V6 variants which have enough power in their own right (most of the time,) even with the intake valve timing and duration altered.
 
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The Prius is efficient because of the engine, not the hybrid system believe it or not. The hybrid system is to make up for the power loss from running a modified atkinson cycle because partial power of a small engine isn't enough. The gas mileage comes from how the engine has a higher effective expansion ratio versus compression because the intake valve is kept open through part of the compression stroke. This is why the Prius engines can get away with an effective expansion ratio of 14:1 which is higher than most gasoline vehicles which is where the higher thermal efficiency comes from. The prius is not the only vehicle that does this and not all of them have the hybrid system, such as the V6 variants which have enough power in their own right (most of the time,) even with the intake valve timing and duration altered.

It's very much a team effort, and I appreciate the enlightenment on the engine; hadn't known that. A Prius wouldn't manage its stellar city economy without the hybrid system and the associated regen braking.
 
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The Prius is efficient because of the engine, not the hybrid system believe it or not. The hybrid system is to make up for the power loss from running a modified atkinson cycle because partial power of a small engine isn't enough. The gas mileage comes from how the engine has a higher effective expansion ratio versus compression because the intake valve is kept open through part of the compression stroke. This is why the Prius engines can get away with an effective expansion ratio of 14:1 which is higher than most gasoline vehicles which is where the higher thermal efficiency comes from. The prius is not the only vehicle that does this and not all of them have the hybrid system, such as the V6 variants which have enough power in their own right (most of the time,) even with the intake valve timing and duration altered.
The engine is optimized to be generator, but that doesn't mean it has to be involved forever-more; the reason we started seeing plug-in hybrids ten years back is because the changing battery chemistry means we can fit enough range for something useful in-town!

Once the battery-only-range gets far enough (versus fuel + engine), then the engine in your plug-in-hybrid disappears completely; it was only a matter of a decade!
 
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The problem for me is still cost

My car cost $14,000 new (23 years back) and has since burned about the same in fuel (after 220,000 mi) so an electric car would not save me money;
also the fact that some of that fuel money stayed invested for some time.

But I still look forward to the day I run an electric vehicle, but that may take another decade.
 
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The problem for me is still cost

My car cost $14,000 new (23 years back) and has since burned about the same in fuel (after 220,000 mi) so an electric car would not save me money;
also the fact that some of that fuel money stayed invested for some time.

But I still look forward to the day I run an electric vehicle, but that may take another decade.

$7500 tax credit on some PHEVs makes a big difference. (Only those with 40+ miles of charge qualify, but the 20+ mile cars still have a partial tax credit)

The PHEV Honda Clarity would likely be cheaper than my current car for example. Alas, Sedans are dying in this country, and the Clarity has been discontinued. I guess the top PHEV will now be the Rav4 Prime (smaller SUV form factor)

EDIT: Honda Clarity 2021 are still on sale around me. They start at $33,000, so the $7500 tax credit effectively drops the price down to $25,500 base value. Not bad for a 5-door sedan, especially in this market where everything is overpriced. (Yes, this is _today's_ price, though all the inventory is sold out...)
 
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The engine is optimized to be generator, but that doesn't mean it has to be involved forever-more; the reason we started seeing plug-in hybrids ten years back is because the changing battery chemistry means we can fit enough range for something useful in-town!

Once the battery-only-range gets far enough (versus fuel + engine), then the engine in your plug-in-hybrid disappears completely; it was only a matter of a decade!
You're not wrong. Double the range of a typical EV and even here in NH, it could work. A full tank of gas can get my to my parent's house in Maine, 4 hours away. Tesla can do it under ideal circumstances with one of the long range variants without a charge in-between. With my Subaru I can make the entire trip on a single tank easy (at >34 MPG I might add,) and filling the tank takes a couple minutes once the pump is going. If I go to visit them in the winter (which can get very cold up here,) then my range is reduced and there are limited areas in Maine to charge, but it is doable. Once I get to my destination, I probably don't have 230v for charging either, so that's 120v at a snail's pace.

I guess my point is that gasoline is still far more convenient if you're not just focused on driving locally. If you're not going long distances, EVs make a lot of sense, but until the range can match or exceed ICE vehicles, like closer to 400 or 500 miles, the shortcomings of recharge locations and times will continue to be the bane of EVs, at least for the kinds of commutes I've had to deal with traditionally.

With that said, I don't go far distances very often anymore. So it's the exception rather than the rule since I work remote now, but I always consider the furthest I'll need to drive.

All in all, I agree with your assessment, just maybe not the outlook. I don't see the ICE being dead in 10 years in the US, forget developing nations.

EDIT: Honda Clarity 2021 are still on sale around me. They start at $33,000, so the $7500 tax credit effectively drops the price down to $25,500 base value. Not bad for a 5-door sedan, especially in this market where everything is overpriced. (Yes, this is _today's_ price, though all the inventory is sold out...)
When I bought my 2015 Subaru Impreza brand new, the sticker price was 19.5k USD. Base model, sure, but new nonetheless. :laugh:
It has 138k miles on it now.

It's very much a team effort, and I appreciate the enlightenment on the engine; hadn't known that. A Prius wouldn't manage its stellar city economy without the hybrid system and the associated regen braking.
Toyota does crazy things with engines. The D4-S system is another good one (direct injection + port injection.)
 
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guys do you think that renewable fuels like ethanol are making great strides. a lot of countries are trying to go E85 very soon, and make flex fuel fuel capabilities mandatory in cars.
Is this going to impact hydrogen cars? Because the only adv they had was long range and storage was light. With ethanol becoming acceptable, that takes away its main advantage right?
 

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guys do you think that renewable fuels like ethanol are making great strides. a lot of countries are trying to go E85 very soon, and make flex fuel fuel capabilities mandatory in cars.
Is this going to impact hydrogen cars? Because the only adv they had was long range and storage was light. With ethanol becoming acceptable, that takes away its main advantage right?

I dunno how it is in the rest of the world, but despite E85 compatibility from the factory in a lot of American cars it never took off. Yes, it's great for power and track use, but it gets horrible mileage and generally isn't regarded as being any "greener" than gas, especially when you take into account its production.

Basically, if you don't live next to an E85 station that has it for cheap, you're not going to be filling E85. And whether you can find an E85 station is very dependent on where you live.

Not sure whether E85 can survive without government subsidies, let alone become popular enough to be a real alternative to gas.

e85.png


Toyota does crazy things with engines. The D4-S system is another good one (direct injection + port injection.)

Dual injection like Ford and Toyota is not so much a "feature" as it really is just a band-aid for direct injection, as the port injectors' presence calms most of the fear about buildup on the back of the valves. Or, what DI should have been in the first place, if you like. It doesn't do anything to improve fuel economy on its own (yes I'm aware of all the theoreticals that port injection makes up for the cold startup period of direct injection, etc.).

Atkinson cycle is equally situational (though yes, it works great for the 2ZR in the Prius). 2GR-FKS is a good example where all these bells and whistles have just resulted in an uncompetitive engine that has neither power nor efficiency.
 
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It doesn't do anything to improve fuel economy on its own (yes I'm aware of all the theoreticals that port injection makes up for the cold startup period of direct injection, etc.).
The biggest issue with DI is definitely the carbon buildup on the intake valves, but you can mitigate that with a good air-oil separator, however there are a couple other shortcomings of direct injection which does impact emissions and efficiency at the same compression ratio. The main bit in that respect has to do with the amount of time that the fuel has to mix with the air. An issue with DIs under heavy load or high RPM tends to be the production of particulate matter much like diesel engines because there are pockets of fuel that are more rich than the surrounding charge because there isn't enough time for the fuel to mix with the air to have a charge with a relatively consistent AFR. Stratified charge is a good way to run leaner than you would otherwise, but you still have the same emission issues.

Toyota's D4-S system doesn't just use the port injectors for occasionally cleaning the intake valves, they tend to almost always work together except under really high load at high RPMs.
 
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The Prius is efficient because of the engine, not the hybrid system believe it or not. The hybrid system is to make up for the power loss from running a modified atkinson cycle because partial power of a small engine isn't enough. The gas mileage comes from how the engine has a higher effective expansion ratio versus compression because the intake valve is kept open through part of the compression stroke. This is why the Prius engines can get away with an effective expansion ratio of 14:1 which is higher than most gasoline vehicles which is where the higher thermal efficiency comes from. The prius is not the only vehicle that does this and not all of them have the hybrid system, such as the V6 variants which have enough power in their own right (most of the time,) even with the intake valve timing and duration altered.
Again, totally wrong in so many ways:
  1. It is not atkinson cycle, but Atkinson cycle. Somebody actually wrote many research papers, to have his name correct with big letter.
  2. It is not "effective expansion ratio" of 14:1, but "compression ratio" of 13:1. Engines achieve power of stroke by compressing of air, not by effective expansion.
  3. Point of Atkinson cycle in Toyota engine is that it has "changeable compression" inside that stroke, which give the engine lower air intake in that stroke. Lower air means lower fuel dispensing, which means lower consumption, but also less power on lower throttle setting.
  4. Engine thermal efficiency is up to 40%, which is quite higher then cars used to have in Otto engines which were 30~33% (without any special valve technics).
  5. What V6 engines does is not using thermal efficiency in their work, but getting some cylinder not working at all. So those cylinders can only consume more power by friction. But as it is not so much power & those strokes are not needed (with lower throttle positioning) - only thing being consumed is air without fuel. & that is the purpose of that system, not consuming FUEL. But those system do power down on the unit by not using cylinders, keep one part of the engine colder then the other (which makes other problems after 300k km or miles), they DO NOT alter valve train at all (so compression stroke is slowing engine down) & the engine is not very efficient at all in that more - other then not using fuel.
Many things are simply not true. & you need to be a mechanical engineer to understand those things.
 
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Here is what I understand

The original Atkinson proposal had an exhaust stroke longer than the intake

(1) Atkinson Cycle Engine - Bing video

but the modern variations achieve this through a blow-back trick; namely to keep the inlet valve open during the early part of the compression stroke, so reducing its effective 'length'; this avoids the need for a fancy crank (see the above animation).

The whole idea is to take advantage of the larger volume of exhaust gas (it being hotter) and so not waste the final expansion.
 
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Engines achieve power of stroke by compressing of air, not by effective expansion.
You better stick with complaining about me not using a capital letter because your understanding of the thermodynamic cycle in an ICE is fundamentally flawed.
Screen Shot 2021-12-03 at 6.14.18 AM.png

http://web.mit.edu/2.61/www/Lecture notes/Lec. 03 Engine cycle analysis.pdf
Many things are simply not true. & you need to be a mechanical engineer to understand those things.
There is a lot of irony with you saying this when your own facts are wrong. Toyota's engines let less air into the engine by manipulating the intake valve timing, that effectively reduces the compression ratio but keeps the expansion ratio the same. The reason they need to do this is because you'd have knock or non-ideal ignition timing to compensate for it (if possible given the max temp of the charge in the cylinder.) Toyota is trading max power for efficiency by doing this and the end result is an expansion ratio that's larger than the effective compression ratio. This lets the engine extract more work from combustion for the amount of fuel burnt. Take your own advice, bub.
 
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Actually I like Toyota's variation better than Atkinson's original since one could adjust the compression ratio (with variable valve timing) and so the engine could optimize itself for the grade of fuel being used, altitude, etc. Of course one would depend on the knock sensor and if this broke that would be a problem.

We are way off topic, but I actually feel that is appropriate.

Right, but you should also check out how VVT & i-VVT engine works in Toyota. Except them, Mazda has developed a Atkinson engine also, which works differently than Toyotas.

How Atkinson engine works (by mechanical engineer).

Toyota's Dynamic Force Engine.

Mazda's SPCCI engine (Skyactiv-X).

How is Mazda's an Atkinson engine?
 
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... so the engine could optimize itself for the grade of fuel being used, altitude, etc. Of course one would depend on the knock sensor and if this broke that would be a problem.

All* modern engines already do this for ignition timing. If the ECU gets bad or no signal from the O2s, it'll fall back on a failsafe mapping. Presumably the same strategy would be used for variable compression.

*Probably not literally "All", but close enough to.
 
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What I am worried about is the sensor says (falsely) no knock and so the engine just keeps upping the compression ratio.

The trick of course is for the engine to periodically go to max compression, and if no knock is detected assume a faulty sensor.
 
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When I bought my 2015 Subaru Impreza brand new, the sticker price was 19.5k USD. Base model, sure, but new nonetheless. :laugh:
It has 138k miles on it now.

Impreza is a compact Sedan though. It seats 5 but your rear passengers will feel bunched up.

Honda Clarity is +4 inches wider and +20 inches longer. Cars of this size normally cost in the $22,000ish range. So $25,000ish for PHEV (After the $7500 credit is factored in) is a bit of a premium, but the gasoline savings will almost certainly win over in the long run.

That's why I liked Honda Clarity PHEV and GM Volt PHEVs. They actually were cost-effective at their jobs.

guys do you think that renewable fuels like ethanol are making great strides. a lot of countries are trying to go E85 very soon, and make flex fuel fuel capabilities mandatory in cars.
Is this going to impact hydrogen cars? Because the only adv they had was long range and storage was light. With ethanol becoming acceptable, that takes away its main advantage right?

E85 is too expensive in the USA. I have a flex-fuel vehicle, so I can use both E85 and E15 gasoline. E85 gives me ~220 miles of range, while E15 gives me 330 miles of range.

So I lose well over 30% of my range, meaning E85 needs to be 30% cheaper before I seriously consider it as a daily fuel source. Unfortunately, E85 is maybe 10% cheaper at best than regular gasoline.
 
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Actually the big problem is E85 has high octane, but one is not taking advantage of that; so a variable compression Atkinson cycle would be very useful.
 
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Actually the big problem is E85 has high octane, but one is not taking advantage of that; so a variable compression Atkinson cycle would be very useful.


1.5 US gallons (5.7 litres) of ethanol has the same energy content as 1.0 US gal (3.8 l) of gasoline.

The energy content ethanol is 76,100 BTU/US gal (5.89 kilowatt-hours per litre), compared to 114,100 BTU/US gal (8.83 kWh/l) for gasoline. (see chart above)

This is determined by just burning 1-gallon of gasoline, and comparing the amount of heat-generated compared to 1.5-gallons of Ethanol. It seems like Ethanol simply has less energy density. No engine design can fundamentally alter a fuel's potential energy.
 
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It's not just energy content, it's also efficiency; and high compression means higher efficiency.

So I disagree, an efficient engine can use more of the fuels chemical energy; that's how diesels work.
 
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It's not just energy content, it's also efficiency; and high compression means higher efficiency.

So I disagree, an efficient engine can use more of the fuels chemical energy; that's how diesels work.

If you have a 40% efficient miniature E15 / gasoline engine (small enough to fit in a car), and you build a 40% efficient Ethanol / E85 engine (also small enough to fit in a car), then you're basically done.

That's basically my car. I lose damn near 30% of fuel economy on E85 compared to E15. This suggests to me that my engine burns Ethanol about as "efficiently" as it burns gasoline (especially when you consider that E85 is only 85% ethanol, and that E15 fuel is 15% ethanol).

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Sure, there are more efficient engine designs. But those are called PHEV engines or Electric cars. It turns out that burning gasoline at a steady RPM at a steady and predictable torque leads to better efficiency. The issue with typical ICE cars is that the engine-designer needs to have a large RPM / torque curve for decent performance. Hybrid engines or PHEVs on the other hand, can turn a generator, and closely tune their engines to be efficient in a narrow and predictable RPM / Torque band.

The thing about the pro-electric guys is that electric engines are far more efficient. So electrifying the engine makes sense from an efficiency perspective (not only for the gasoline efficiency, but also for regenerative braking and other such tricks). But I'm still bearish on Li-ion as a storage mechanism. We definitely want electric engines, but using H2 fuel-cells, or even gasoline generators, to run those electric engines is a surprisingly good strategy.
 
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