Tesla semi

[vvanders]

<insert joke about throwing gasoline on the fire>

Anyway, getting back on topic.

From my understanding(which I'm sure is not complete), power to three phase motor is a function of how much current the wires can sustain(aka heat dissipated from resistance) and physical strength.

Tesla moved to a single-gear transmission from the Roadster because it turns out electric motors are really good at shredding transmissions.

 

[California]

Tesla moved to a single-gear transmission from the Roadster because it turns out electric motors are really good at shredding transmissions.

But - wouldn't a heavy truck need compound gearing at least to get started out of someplace that is such a difficult start that it is at the limit of (good) traction? Huge torque is great but multiplying it with gearing seems like it would still be needed in some cases, similar to present two-speed axles that are used to get started moving. Anybody know?

 

[TemporaryKubotaOwnerMark]

just think of all that methane, pretty explosive I hear...
I think Bessie gets a pass here.

Hmmm. Bessie gets a... pass?

That might be an unfortunate choice of words....

 

[cqaigy2]

But - wouldn't a heavy truck need compound gearing at least to get started out of someplace that is such a difficult start that it is at the limit of (good) traction? Huge torque is great but multiplying it with gearing seems like it would still be needed in some cases, similar to present two-speed axles that are used to get started moving. Anybody know?

I don't think locomotives have gear boxes, so probably not?

 

[vvanders]

But - wouldn't a heavy truck need compound gearing at least to get started out of someplace that is such a difficult start that it is at the limit of (good) traction? Huge torque is great but multiplying it with gearing seems like it would still be needed in some cases, similar to present two-speed axles that are used to get started moving. Anybody know?

I'd be pretty surprised if that was the case.

I know on our Tesla I can go from about couple hundred watts, which is about as much as you'd get from hopping out and pushing up to ~450hp(~325kW) seamlessly.

The P90DL I had as a loaner(~700hp) was exactly the same. I think as long as they have enough resolution in the PWM portion of the power circuit it shouldn't be an issue.

 

[toppop52]

I am guessing the dealership burned down because of all the gasoline in cars. It might started as battery short but without gasoline it would be no event.

You壇 lose, the battery fire spread to the workbench, where it got into the parts washer then the bulk oil tank for the furnace. And is didn稚 burn down, it was extensively damaged though, due as much to smoke and water as fire.

 

[toppop52]

Just observations made from the passing summer groups of riders.

Cool; you're right, I don't know what it is. Comfort & enjoyment does come into my realm of feeling good though.

Got some sixty year old scars that may mean I went through a cool stage though.

You and I both my friend! :drink:

 

[toppop52]

I think electric road tractors are an excellent choice, the rate we are advancing, they will soon be cost effective.
Don’t misunderstand my questions and devil’s advocate tone, I think the future holds many forms of power. I just want them to stand on their own without artificial price fixing at taxpayer expense, and I want people to admit their many shortcomings, internal combustion, fusion, fusion, wind, all have their problems and safety concerns, so to do EV’s. Once we admit and recognize that, the sooner we advance.

 

[3 Horse Ranch]

It takes a lot of power to keep 40 tons moving at 60 mph up and down hills bucking all that wind resistance for 500 miles a day. Not to mention trucks that are sleeper teamed that basically never stop moving except for fuel, meals and showers. The truck I last drove had a display that showed percentage of power used, it rarely dropped below 50%. Granted it was pulling 105,500# and was not designed to be aerodynamic. Still, it was constantly using 300+ hp just to move up and down the freeway. Average fuel milage was 4.1 mpg. Eighteen tires on the highway is a lot of friction to overcome, mine had 28, hence the milage. Battery technology hasn't progressed far enough yet, give it another decade or so.

 

[California]

Tesla I can go from about couple hundred watts, which is about as much as you'd get from hopping out and pushing up to ~450hp(~325kW) seamlessly.

Ok, full torque from zero rpm doesn't need to be multiplied to get a lot of weight started moving.

Thanks! I just learned something new.

 

[Egon]

Hydrogen cells may have some merit. Refuelling would be in the same time frame as hydrocarbon.

 

[toppop52]

The old stories on hydrogen were, “Just fill the tank with sea water and drive for a month.” I don’t see that one, but the hydrogen cells are interesting.

 

[PILOON]

I'll add another factor to consider.
TAXATION
Roads are generally paid for and maintained via taxation income and that is generally levied at the gas pump.
Will all road maintenance taxation be applied at large? at the charging stations? and then if plugged in at home you then avoid road taxes.

Now then diesel fuel is used for trucking because there is more BTU's of energy than gasoline per gallon (thing weight and volume)
Batteries are HEAVY (and bulky) so more HP is needed to haul the same loads.

A comparison is aircraft. They never simply fill up but carefully calculate how much fuel needed to go from A to B.
So much true that the FAA had to regulate to assure there was a suitable reserve to get to the next closest airport.
It cost fuel to haul fuel! and that's money. (profit)

Maybe the answer will become, one battery to go from A-B and 2 batteries to go from A-C. etc.

I always think of fork lift trucks and the massive batteries just to maintain a shift.\
In some cases users have up to 3 batteries per forklift just to cover shifts.

 

[houstonscott]

I'll add another factor to consider. TAXATION Roads are generally paid for and maintained via taxation income and that is generally levied at the gas pump. Will all road maintenance taxation be applied at large? at the charging stations? and then if plugged in at home you then avoid road taxes. Now then diesel fuel is used for trucking because there is more BTU's of energy than gasoline per gallon (thing weight and volume) Batteries are HEAVY (and bulky) so more HP is needed to haul the same loads. A comparison is aircraft. They never simply fill up but carefully calculate how much fuel needed to go from A to B. So much true that the FAA had to regulate to assure there was a suitable reserve to get to the next closest airport. It cost fuel to haul fuel! and that's money. (profit) Maybe the answer will become, one battery to go from A-B and 2 batteries to go from A-C. etc. I always think of fork lift trucks and the massive batteries just to maintain a shift.\ In some cases users have up to 3 batteries per forklift just to cover shifts.

Good thought, how should EV pay to use roads they don't pay for... 32 cents a kilowatt added to recharges?

 

[toppop52]

I'll add another factor to consider.
TAXATION
Roads are generally paid for and maintained via taxation income and that is generally levied at the gas pump.
Will all road maintenance taxation be applied at large? at the charging stations? and then if plugged in at home you then avoid road taxes.

Now then diesel fuel is used for trucking because there is more BTU's of energy than gasoline per gallon (thing weight and volume)
Batteries are HEAVY (and bulky) so more HP is needed to haul the same loads.

A comparison is aircraft. They never simply fill up but carefully calculate how much fuel needed to go from A to B.
So much true that the FAA had to regulate to assure there was a suitable reserve to get to the next closest airport.
It cost fuel to haul fuel! and that's money. (profit)

Maybe the answer will become, one battery to go from A-B and 2 batteries to go from A-C. etc.

I always think of fork lift trucks and the massive batteries just to maintain a shift.\
In some cases users have up to 3 batteries per forklift just to cover shifts.

Taxes are also the reason there is dye in diesel, do you can’t cheat and run #2 heating oil.

 

[Redneck in training]

You can tax polution aka carbon tax. ICE polutes about 5 times more than electric if charged from coal or NG. Electric polutes near zero if chharged from wind, water or solar.

 

[houstonscott]

You can tax polution aka carbon tax. ICE polutes about 5 times more than electric if charged from coal or NG. Electric polutes near zero if chharged from wind, water or solar.

government can tax nearly anything. Your road gas taxes aren't about pollution, they are about paying for the road you are using. I haven't seen any evidence ICE pollutes more then electric, only evidential studies I can find show electric is far more inefficient and maybe the worst thing you could do with electric power would be to charge batteries for automobile transportation. Your wind solar hydro statement is so far fetched in realizing it's not even worth discussing.

 

[California]

re taxation: That's a problem to be worked out. Maybe higher annual vehicle registration fees is the place to collect highway operation cost from all users, if electric energy replaces carbon measured by the gallon. Fees might be based on weight. What are some other alternatives?


Some highway design factoids:

Thickness of freeway pavement is proportional to truck traffic load. Trucks break down highways, cars don't. (as a general design principle).

And width of a freeway - number of lanes - is designed for traffic volume anticipated.

Mass transit - this one is a surprise - is often cheaper, even if heavily subsidized - compared to widening a freeway in an area that is already developed. Widening freeway right of way via eminent domain is controversial, extremely costly, and extremely disruptive to the economy of demolished urban corridors. Rail may seem absurdly expensive but it is still cheaper than adding capacity to an urban freeway. And - taxing the general public to pay for rail is an indirect subsidy to motorists who don't see so many competing cars on the road. (because so many people are on the train instead).

A clear example of rail preferable to widening is BART - the subway that crosses under San Francisco Bay. It's heavily subsidized, fares don't recover operating cost, but it is still a cheaper alternative than building another Bay Bridge to get over to San Francisco.

One more piece of trivia: I don't know if this is true nationwide but it's highly relevant to California where the population grows substantially every year: There are always developers proposing new development beyond the perimeter of urban areas and they all want a freeway to make the land that they bought cheap, out in the boondocks, suddenly accessible to downtown where the jobs are. As you might guess, these guys lobbying for where the highway improvement dollars will be spent next is a major force determining route planning.

And an underlying design principle: it seems to be human nature to want a commute of about 20 minutes. New freeways promote new subdivisions at the new 20 minute perimeter around urban areas. Then 20 years later the freeway is clogged with traffic and there is pressure from the public to widen the freeway .....

 

[4570Man]

You can tax polution aka carbon tax. ICE polutes about 5 times more than electric if charged from coal or NG. Electric polutes near zero if chharged from wind, water or solar.

You're missing the point. Red diesel supposedly isn't taxed and is for off road use. There's a stiff fine if you get caught running it on the road.

 

[Egon]

Each vehicle may end up having a transceiver or some such which records the roads travelled, miles travelled etc. And you get the bill by mail.