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Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

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Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#201
post #87
post #66

Earlier quoted context omitted.

All the crypto mining dying off should free up a lot of grid resources for EVs. I've heard the "grid can't handle all EVs" statement, but have not seen anything backing up the claim. I believe the grid can in fact handle EVs becoming prevalent. We might need more power generation , which could be new plants, and/or residential solar. Baring some kind of crazy legislation requiring ICE vehicles to be crushed or perman…

The global energy usage from crypto was in the ballpark of 120-240 TWh/year, but a couple figures repeated the specific 150 TWh/year figure, so I'll use that. The US's annual gasoline consumption is 135 bn gallons (2021 figure). At around 20 mpg (random estimate because I have to pick something), that works out to 2.7 trillion miles. At 30 kWh/100mi (figure from google), that works out 800 TWh if every gas vehicle in…

Crypto was 1/5th of the ENTIRE US CONSUMER TRANSPORTATION (BEV efficiency converted)????

That is an astonishing amount of electricity for something of so little value.

But anyway, to the larger point, I agree the grid impact is overblown, especially since we should be coupling consumer BEVs with home / business / warehouse / commercial solar.

Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#202
post #87

Earlier quoted context omitted.

The global energy usage from crypto was in the ballpark of 120-240 TWh/year, but a couple figures repeated the specific 150 TWh/year figure, so I'll use that. The US's annual gasoline consumption is 135 bn gallons (2021 figure). At around 20 mpg (random estimate because I have to pick something), that works out to 2.7 trillion miles. At 30 kWh/100mi (figure from google), that works out 800 TWh if every gas vehicle in…

Interesting to note that there is ~30kWh of energy in a gallon of gasoline, so the reason EV would only take 20% of US electricity consumption is that they are 5x more efficient (than the 20mpg gas figure used). Indeed seems manageable.

I did not verify his figures, but his methodology was BEV efficiency, not the amount of energy in a gallon of gasoline. Electric drivetrains and cars are designed ground-up for efficiency to a degree that ICE cars are not, as well as the fact that something like 80-90% of energy in a gallon of gasoline is wasted (60-70% due to Carnot efficiency alone).

Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#203
post #200

Earlier quoted context omitted.

I don't think long haul trucking is that hard to electrify. If we take the current (Pepsi) Tesla semi that can (allegedly) do 500 miles, and you also tow a trailer that is a "range extender" trailer (as in UPS already does multiple trailer towing), then you could recharge by just unhitching the depleted trailer and hitching up a precharged trailer. Lithium-Sulfer and/or solid state will also likely come into play. Av…

Not so fast here. From what I've been able to find out (telling that Tesla itself did not release any figures on weights for their semi) the Tesla Semi will weigh about 10 tons (without trailer), which is slightly more than even the most powerful, longest-range long-haul trucks that have ranges of 2000+ miles. So you have (conservatively) 5 tons less cargo which is a 25% reduction from the typical 20 tons. Then you h…

But the tesla truck is basically 1.0.

Lithium-sulfur, Sodium-sulfur, and solid state variants plus a host of other tricks are coming down the pipeline in the next 5-10 years. A conservative estimate is that batteries will be 2x better than the current (the papers indicate 4x but let's see what happens).

The other aspects here:

- BEV semis are cheaper to operate long-term since electricity is cheaper than diesel (even without the carbon tax diesel operation should be paying), most calculations 5 years ago before the current 5-6$/gallon diesel crisis showed that.

- electricity will continue to drop in price as Solar/Wind continue to drop in LCOE over then next ten years

- BEV batteries will continue to drop rapidly in price over the next decade until the initial cost of BEVs will be structurally less than any ICE drivetrain

- highway self-driving, or highway "pack" driving, is going to get a LOT more prevalent. Highway self driving for trucks will likely converge/evolve with infrastructure to enable long haul trucks to self-drive at slower rates (more efficient) overnight and then be operated at "normal" speeds during the day.

So the number of trucks will probably be irrelevant in the long run. The key metric is probably the one that always mattered: how much to move a ton of cargo per mile. BEVs are probably close or will pass in 5 years ICE transport on equipment / fuel / energy costs alone. In ten years batteries will be so cheap that ICE drivetrains will simply not be a sane option except in the most extreme cases (long haul ultra-rural routes, long haul in deep winter, etc).

Maintenance wise, BEVs are simpler, less fluids, etc. They also might be more resilient to breakdowns. If you have a HUGE battery pack and three axles of power delivery (the Tesla design apparently uses the three axels for acceleration and then only one at cruise), then if one of the drive motors fails, you can fallback to another drive motor usually used only for acceleration. You can subdivide the huge battery pack and if part of it goes out, you have enough juice and drive motors to limp to someplace.

And again, long range can probably be boosted with swappable extra power trailers. Recharge rates will be moot because the power trailers are precharged. The power trailer can probably be shaped to increase the semi's rear aerodynamics better, and increase the overall efficiency of the semi as well.

Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#204

Earlier quoted context omitted.

My chainsaw runs on Aspen, which is a synthetic replacement for gasoline. It doesn't cause a headache when I'm exposed to the exhaust fumes for long times. It's quite expensive though, about 4€/l (15€/gallon).

Aspen2 is not green. its Aspen 4, which is part of the gasoline distilation process, but the oil they mix in for the 2 stroke engines is a syntetic bio oil. https://www.aspenfuels.us/knowledge/what-is-alkylate-fuel/wh...

Good to know, thanks!

Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#205
post #200

Earlier quoted context omitted.

Not so fast here. From what I've been able to find out (telling that Tesla itself did not release any figures on weights for their semi) the Tesla Semi will weigh about 10 tons (without trailer), which is slightly more than even the most powerful, longest-range long-haul trucks that have ranges of 2000+ miles. So you have (conservatively) 5 tons less cargo which is a 25% reduction from the typical 20 tons. Then you h…

But the tesla truck is basically 1.0. Lithium-sulfur, Sodium-sulfur, and solid state variants plus a host of other tricks are coming down the pipeline in the next 5-10 years. A conservative estimate is that batteries will be 2x better than the current (the papers indicate 4x but let's see what happens). The other aspects here: - BEV semis are cheaper to operate long-term since electricity is cheaper than diesel (even…

> [improving battery tech]

This would be nice if it actually happens, but so far the new chemistries still have many unsolved fundamental issues, not to mention safety issues when increasing energy density further.

> [cost per mile / energy costs]

No arguments here, eventually EV running costs per vehicle will be cheaper. But there will probably be surge pricing for charging when renewable output is low. It won't be easy to manage that risk from a business perspective.

> [self-driving]

Sorry to be snarky, but weren't there supposed to be thousands of people's Teslas operating as robo taxis for 5 years now? I'll believe self-driving truck convoys when I see one operating without journalists or politicians watching.

Also, outside of your "power trailers" (see below) running the truck continuously like that would require battery swapping, which is a promising idea but also has a long list of unsolved problems (wear&tear, additional frames and braces required with swapable battery, cost of labour for swapping a truck's battery 4x per day).

> So the number of trucks will probably be irrelevant in the long run.

This left me dumbfounded. Double the traffic, double the CapEx, double the inspections/maintenance doesn't matter at all?

> [range extending trailers]

So your EV truck already lost 5+ tons of cargo space to a battery, now you wanna hitch an extra trailer (another 5~ tons for the frame and 5 tons for another battery. Since the max legal weight is 40 tons your range-extended Semi can now only transport around 10 tons of cargo compared to 25 tons for the most capable diesel trucks.

Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#206
post #198

Earlier quoted context omitted.

Good for them. An electric Miata would require a battery with an unheard-of energy density.

Explain Aptera.

“Someone has more venture funding than taste”

Re: Mazda has tested a synthetic fuel in an unmodified MX5 on a 1000-mile road trip

#207
post #15

> it’s safe to assume that it’ll likely charge a hefty premium over traditional gasoline. > Also worth noting is that while, yes, this synthetic fuel appears to make vehicles slightly more efficient, it still greatly trails the efficiency of EVs. Consequently, vehicles using this fuel will likely always be more expensive to drive per mile than their electric equivalents. So why are we doing this again?

Because we could move the entire current stock of cars over to less carbon intensive fuel without having to build an entirely new fleet. Keeping in mind that manufacturing new cars (and the associated resource extraction) is extremely carbon intensive, then a carbon neutral-ish fuel might actually be the best option overall on a meaningful timescale.

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