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When I started this thread, I could not have anticipated its longevity.

The only other thread I've started that beats this is about Rostra cruise control.

This tells me that people like cruise control and debating alternatives to petrol.

I started a TED talk thread, but that's gone nowhere. Maybe someone will throw up a TED talk by Elon Musk.
 

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One more reply that I think I have posted before, but I don't see it on this thread. I think ione key element missing in this EV scenario is changeable batteries. If quick turn-around is what we want (and it IS) then a quick-change battery pack is the best answer. All of the vehicle manufacturers should get together (should already have gotten together) and agree on a standard battery platform. Put the battery pack on the bottom of the vehicle. You pull into a service station, the attendant comes out with a thing like a pallet jack, unclamps the battery, wheels it into the station, wheels out another one, jacks it up into place, takes your $75 or whatever (about the price of a tank of fuel for my truck) and you are on the road in 5 or 10 minutes. Yes, there would have to be some sort of system to allow for getting a defective battery pack, some kind of service truck to come out on the road and replace one if it died on you, etc. (Which is a good idea anyway.) The battery packs would then slow-charge overnight at the station.

I'm sure there are details I haven't thought of, but I know it's not going to happen anyway, so it's just a thought experiment.
 

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The problem with changeable packs is the volume needed, and the weight. Probably work fine for a semi, but for passenger cars the batteries are stashed in a number of places, usually low, to keep the CG manageable. Maybe some day, when the power density, related to volume, is much higher, and you could get by with a couple of cubic feet. Right now for a medium sized pack, the weight might be 800-1000 lbs. particularly fro replaceable packs, the 'boxes' would need to be fireproof as well, upping the weight.
 

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please trynto think of how many people go into a roadside gas station on a Thanksgiving long weekend. Many gas stations will see as many as 2,000 cars coming into fill up. Now imagine those cars are all coming in to get a 800 pound battery changed. 2,000 off them. where would they be stored? How would they be kept on charge while waiting for a home? And most of all, how would a service station manage all the different batteries that individual automakers will manufacture? The gas that goes in a Mercedes is the same that goes into a Kia, octane aside. I can assure that a Mercedes lithium ion battery looks nothing like a Kia one or Chevy version. This is the most unlikely solution of all.
 

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Another try at a hydrogen car:


13 pounds of hydrogen roughly two gallons of gas. Even at a 3 to 1 energy ratio in hydrogen's favor, 6 gallons. How far can you go on 6 gallons? Maybe better than I think, 'cause the drivetrain efficiency is higher than IC by maybe 2 to 1 or better. Probably fewer high-pressure hydrogen stations than electric charging stations. And I can see some drunk standing next to his Bimmer with a cigarette in his mouth, fumbling with the connector.
 

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For a while now I've thought that the best use of hydrogen would be as short term energy storage at a large wind turbine/solar array/gas turbine powerplant. During good sun and wind periods excess electricity would split water into hydrogen and oxygen, the hydrogen would be stored in a large underground high pressure tank. During bad sun/wind periods the hydrogen would power the gas turbine to meet demand.
If it's possible to design a gas turbine that can run on either natural gas or hydrogen then you could have the NG act as the last resort backup if you had an unusually long stretch of limited sun and wind and ran out of hydrogen.

Obviously not cost effective now (or else it would have been done) but down the road, who knows.
 

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For a while now I've thought that the best use of hydrogen would be as short term energy storage at a large wind turbine/solar array/gas turbine powerplant. During good sun and wind periods excess electricity would split water into hydrogen and oxygen, the hydrogen would be stored in a large underground high pressure tank. During bad sun/wind periods the hydrogen would power the gas turbine to meet demand.
If it's possible to design a gas turbine that can run on either natural gas or hydrogen then you could have the NG act as the last resort backup if you had an unusually long stretch of limited sun and wind and ran out of hydrogen.

Obviously not cost effective now (or else it would have been done) but down the road, who knows.
 

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I kind of wonder whether any of the storage schemes try to recover the huge amount of energy needed to compress hydrogen to the very high pressures needed to store a significant amount? Hopefully some of the new schemes will require far less energy to store and recover the hydrogen.
 

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More than you apparently :rolleyes:

Hydrogen can be stored in three different ways

Hydrogen can be stored in three ways: As a compressed gas in high-pressure tanks. As a liquid in dewars or tanks (stored at -253°C). As a solid by either absorbing or reacting with metals or chemical compounds or storing in an alternative chemical form.

You can run any ICE engine on hydrogen and as far as loss ...the energy is lost from renewables if it cannot be used. It can be used as a grid level battery

hydrogen can be used as a fuel for portable (vehicles) or stationary energy generation. Compared to pumped water storage and batteries, hydrogenhas the advantage that it is a high energy density fuel.
 

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My question related to the energy required to compress the hydrogen to the very high pressures needed to store a significant amount of hydrogen gas (integral PdV). Generally a large portion of that energy goes to heating the gas, which is then lost if there is any significant storage time. Cryogenic storage, in addition to being complex and difficult on a vehicle scale, also entails considerable energy expenditure to liquify the gas. And there are hazards to transferring liquid hydrogen due to extremely low temps. Adsorbing or absorbing the gas into hydrates, clathrates, or MOF's, seems the best real-world method, but storage capacity is not yet up to useful levels. And for vehicle operations, storage and transfer will likely involve either extremely-high-pressure gas or liquid hydrogen, troublesome at best.

On the other hand, binding the hydrogen in a liquid synfuel can be done at the source and can utilize present infrastructure for transfer and storage. 'Designing' the fuel for easy 'cracking' to release the hydrogen for fuel-cell or other use should be relatively easy, I'd think. Very possibly the fuel cell itself would separate out the hydrogen from the 'carrier'. Seeing some big strides in semi-permeable and selective membranes. If necessary, the residual 'carrier' would be recycled back for re-use, rather than released to the environment. A task for chemical engineers. Conventional petrofuels contain around 14% hydrogen by weight. Presumably that can be improved.

Batteries will provide good near-term transition from fossil fuels. But will almost certainly be supplanted by liquid synfuel and fuel cells in a decade or two. Unlikely that weight and volume requirements will advance sufficiently to make them good long-term prospects. Even with the efficiecy of electric vehicles, tough to make a 4000 lb vehicle energy efficient.

Ore perhaps the autonomous vehicle revolution will render it moot. Go until the (public) vehicle runs out of charge, transfer yourself and your goods to another vehicle, continue on your way.

While hydrogen makes a good IC engine fuel, the inherent energy losses of an IC engine make that a less efficient and workable proposition.
 

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Pretty sure with this current focus on germs, autonomous cars you share with the "filthy" masses has been set back a huge notch in desirability.
 

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Pretty sure with this current focus on germs, autonomous cars you share with the "filthy" masses has been set back a huge notch in desirability.
Automatic Clorox spritzer as soon as the car detects people have left. Problem solved. :)
 

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Not to get too far afield, but one of the unanswered questions is whether the infection can actually be transmitted on a surface, rather than face-to-face. Yeah, the bugs can live there, but can they infect? And they are making strides on self-disinfecting surfaces. More likely the car will have a camera that scans you for fever or other sickness indications and refuses to unlock the doors. Be a bummer if it detects that you are inebriated to the point of refunding and refuses to give you a ride, just like your former best mates.
 

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I'm pretty sure that's an answered question ....can you become airborne infected from a surface no, can you touch something with the virus and then touch your face and get infected ...you betcha.

That's one reason the masks are now recognized ...not so much for airborne prevention tho they do that in the case of N95.
For the average joe with a surgical mask it keeps you from touching your face AND offers some protection for others around you from your sneezes, coughs and singing.
 

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...

On the other hand, binding the hydrogen in a liquid synfuel can be done at the source and can utilize present infrastructure for transfer and storage. 'Designing' the fuel for easy 'cracking' to release the hydrogen for fuel-cell or other use should be relatively easy, I'd think. Very possibly the fuel cell itself would separate out the hydrogen from the 'carrier'. Seeing some big strides in semi-permeable and selective membranes. If necessary, the residual 'carrier' would be recycled back for re-use, rather than released to the environment. A task for chemical engineers. Conventional petrofuels contain around 14% hydrogen by weight. Presumably that can be improved.
goods to another vehicle, continue on your way.
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While hydrogen makes a good IC engine fuel, the inherent energy losses of an IC engine make that a less efficient and workable proposition.
We have hydrogen based synfuels now. We call them petroleum :) and that's by far the best way to carry hydrogen. On it's own it's horrible to store i.e. it'll leak through steel and make it brittle. Yeah, you can absorb it into something but that just makes it heavier than it was and gives you once again far worse energy density than petroleum. Combining hydrogen with anything BUT carbon isn't a good option because the compounds are toxic and or the waste products are solids, toxic, corrosive or all three. CO2 is a gas, isn't intrinsically toxic and only slightly corrosive. The only near contender is ammonia and that's a horror to deal with compared to petroleum and has far worse energy density.

...
And agreed on the efficiency thing with an IC engine but mobile fuel cells have similar issues, by the time you've dealt with H2's little problems you probably aren't ahead of just combining it with carbon, turning it into a liquid and using a conventional engine. And IC engines CAN be more efficient than they are now but again people generally don't like the tradeoffs (cost, reduced peak power).
 

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Efficiency is relatively meanlingless as you are storing energy where from sources that would otherwise be wasted.

Gas storage method could help next-generation clean energy vehicles
Tremendous amounts of hydrogen and methane can be stored in nanoscopic pores
Date:April 16, 2020Source:Northwestern UniversitySummary:A Northwestern University research team has designed and synthesized new materials with ultrahigh porosity and surface area for the storage of hydrogen and methane for fuel cell-powered vehicles. The materials, a type of a metal-organic framework (MOF), can store significantly more hydrogen and methane than conventional adsorbent materials at much safer pressures and at much lower costs. A one-gram sample of the material (with a volume of six M&Ms) has a surface area that would cover 1.3 football fields.
more

Carbon based fuels have to go tho a closed cycle might work - there is some effort along those lines.
 

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Looks like the cheaper Taycan is becoming available:


Still out of my price range by a factor of 3, but somewhat more price-competitive. Kinda funny to see the kvetching about range, in a 500+Hp car that does sub-4 second 0-60, and 155 MPH top speed. I'm guessing, if you could control yourself and tiptoe around rather than planting your right foot, that it's go quite a ways farther than the rated distance. Porsche sells performance cars, not economy cars.
 

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I know it's not a true electric car, but I own a 2018 Volt. I would have bought a Bolt, but at the time there was an 8 month wait and I needed a car within 7 days to start a new job.

Now I've just crossed the 2year ownership mark of my 2018 Volt. Since I ride the bike from April to December each year, the 50,000km I've put on the Volt is during winters only. 40,000km have been electric. The Volt has been a great car and a pleasure to drive in the snow and ice. First car or GM vehicle I've owned brand new and I've been fortunate to have a great ownership experience.

When my wife's Civic is ready to go she will take the Volt since she likes it too. I guess that means a full electric for me and if I'm lucky that means something with a little more pep than Volt. For 99% of our driving we don't need a gas car and for the times we do, the Volt can do that for us.
 
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