EREV - A Horsepower Math Problem?

[grottomatic]

Max tow isn't ever going to be a need for 320hp supplied forever though. You can also, in extreme edge cases (start at the bottom of a mountain with zero battery) pull over and generate, go slower than 80mph, or like... start it up and let it recharge itself.

I think that would be reasonable but YouTube testers will exactly seek out edge cases and make the truck look bad and will kill sales off the bat. Hoovies garage did a lot of damage making videos showing Lightning when it first came out towing in the cold. Imagine if TFL had to stop and sit and charge prior to doing the Ike gauntlet - not a good look.

I don’t agree with it but I don’t think ford is going to build another electric truck that isn’t everything to everyone this time around. They werent happy with having the number 1 electric truck with the lightning. If they can’t build something that has no compromise at edge cases they wont build it at all.

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[Lomilar]

I think that would be reasonable but YouTube testers will exactly seek out edge cases and make the truck look bad and will kill sales off the bat. Hoovies garage did a lot of damage making videos showing Lightning when it first came out towing in the cold. Imagine if TFL had to stop and sit and charge prior to doing the Ike gauntlet - not a good look.

I don’t agree with it but I don’t think ford is going to build another electric truck that isn’t everything to everyone this time around. They werent happy with having the number 1 electric truck with the lightning. If they can’t build something that has no compromise at edge cases they wont build it at all.

"Here we are doing the Pike's Peak run having just finished an absolutely stellar overnight bender, having fully depleted our 55kwh battery powering a 7000 watt DJ setup for 12 hours straight... Towing a trailer carrying a Polestar One and a Mazda MX-30, so a totally normal Thursday morning. Let's see if the new 2028 Ford Lightning EREV can dissapoint us again."

 

[Newton]

Aha, I think I see where the confusion (or at least my confusion) comes from. Automakers/journalists have invented a new way to rate generators.

Power flows from the specifically designed 3.6-liter V6 to the on-board generator that makes 174-hp (130-kW). The driver can use the energy to recharge the battery when it’s depleted or to preserve it. The vehicle can use both the generator and the battery simultaneously for maximum power output, while software and drive modes help regulate the charging parameters that includes one for towing.

That parenthesis is doing a lot of work here. You cannot rate a generator by taking two thirds of the horsepower of the source engine. Even in an ideal world with no losses it doesn't work that way. The kW that a generator produces is entirely limited by the rating of the alternator. If you put a 500hp engine on a 20kW alternator you will get exactly the same power characteristics as if you attached it to a 40hp engine. In fact, generator manufacturers may use the same engine produce different ratings of generators simply by putting in a larger alternator (and tuning the engine differently).

Horsepower and torque are not the same thing, a lightweight high-horsepower engine attached to a generator will not be able to produce the same power as a lower horsepower, higher torque engine. This is why diesels are kings for large generators.

I'm not saying that the Ram Rev doesn't work, obviously it does, but I really do not think that it is a 130kW generator.

EVs are so much simpler.

 

[proprepper]

I've put 130k miles on my 2017 volt. It's a weird arrangement erev kind of car. It's been a super car.

It does have a thing called mountain mode? that ensures you have enough high voltage battery to provide full power for going up extended grades. You engage it before you encounter a steep grade mountain pass.

Maybe the truck will be similar setup controls?

 

[chriserx]

Aha, I think I see where the confusion (or at least my confusion) comes from. Automakers/journalists have invented a new way to rate generators.



That parenthesis is doing a lot of work here. You cannot rate a generator by taking two thirds of the horsepower of the source engine. Even in an ideal world with no losses it doesn't work that way. The kW that a generator produces is entirely limited by the rating of the alternator. If you put a 500hp engine on a 20kW alternator you will get exactly the same power characteristics as if you attached it to a 40hp engine. In fact, generator manufacturers may use the same engine produce different ratings of generators simply by putting in a larger alternator (and tuning the engine differently).

Horsepower and torque are not the same thing, a lightweight high-horsepower engine attached to a generator will not be able to produce the same power as a lower horsepower, higher torque engine. This is why diesels are kings for large generators.

I'm not saying that the Ram Rev doesn't work, obviously it does, but I really do not think that it is a 130kW generator.

EVs are so much simpler.

The parentheses is specifically converting horsepower to its metric equivalent.
I really think the main problem comes down to details, engine output are typically rated in both horsepower and kilowatts as well as thermal input. When talking about electricity, we typically only use kilowatts. When others write about engines and specifically engines used as a generator, they typically don't specify which metric they are referring to. Sure we could contextually infer which, but specifics would be nice.
Diesel's are also king due to a much greater thermal efficiency, naturally heavier duty components, etc. Other than cost and emissions, for a generator at least, they are superior to gas in every way I can think of.

 

[Wendy]

We should have a recall drinking game when/if this all comes to fruition. Not sure i can afford or even handle that much alcohol.

I think it’s hilarious you mention a drinking game and then immediately there is a White Claw Ad

maybe Brian AI is listening

 

[ZeusDriver]

That parenthesis is doing a lot of work here.

No. It is simply showing the kW equivalent to the HP (1HP = 746 Watts , the world over, for the last 200 years)

>>You cannot rate a generator by taking two thirds of the horsepower of the source engine. <<
That is not what they are doing. The 130 kW is actually a continuous rating, and the peak rating is considerably higher, up to about 90%- 95% of the engine's peak HP rating, which is over 200 HP. You can rate a generator by taking the sustainable engine output times the efficiency of the generator (which in this case will be circa 95%. ) So getting a 130kW output requires a (130 /.95) input : 137 kW. That is 184 HP, well within the continuous output capability of a normally aspirated 3.6 liter V6.

>>Even in an ideal world with no losses it doesn't work that way. The kW that a generator produces is entirely limited by the rating of the alternator.<<
Or by the HP rating of the engine. In the case above, if the engine can produce 300 HP briefly, the generator will produce (300*.746*.95) 213 kW. With water cooling, the generator could be expected do this for quite a while without overheating.

Take a look under your truck. Those motor boxes contain stuff other than the motor itself.
The motor's rotor is only 8-9 inches diameter, and produces 250 HP. In full regen, it can work as a 250 hp (187 kW) generator.

>>Horsepower and torque are not the same thing, a lightweight high-horsepower engine attached to a generator will not be able to produce the same power as a lower horsepower, higher torque engine. This is why diesels are kings for large generators.<<

This makes no sense at all. A lightweight 50 HP engine will produce exactly twice the KW electric output of a heavy, slow turning 25 hp engine, given equivalent alternators wound appropriately for the RPM. Diesels are great for stationary generators because they are long lasting, due to their heavy construction, because the fuel is less likely to cause explosive fires, and because the fuel has a higher heat content than gasoline.

Are you aware that the motors in your truck can run up to 15000 rpm? But they seem "torquey" don't they?

>>I'm not saying that the Ram Rev doesn't work, obviously it does, but I really do not think that it is a 130kW generator.<<
And why do you think they are lying about that so publicly? It would be impossible to obtain their desired performance with a smaller generator. The famous towing test only requires a 40 mph sustained speed, but few perspective buyers will consider that "locomotive like." After you've spent $100,000 on a truck, you may not want to be passed up by a 50 year old air-cooled VW .

>>EVs are so much simpler.<<
Agreed.

 

[ZeusDriver]

Maybe the truck will be similar setup controls?

Yes, both Ford and Ram would be foolish not to provide this. By integrating the feature with GPS, then the pre-charging could be fully automatic, if the driver desires that.

 

[Heliian]

Generator that puts out that much kW likely won't fit in the truck. I have a 1.0L v twin 18kW Generac in my back yard to power the home when the grid drops, it's fairly large, it would take up at least half the bed space.

I have a 12kw honda 3 cyl. diesel that would easily fit under the hood of any truck. The generator is "big" because it's in a sound reducing box with a built in fuel tank, battery, radiator, intake, exhaust, control panel and inverter. Obviously, it isn't going to have a frunk.

 

[chriserx]

I am going to find it hilarious when an EREV towing a camper exits the interstate, gets to the stoplight and the engine runs full throttle to try and catch up. I figure it's unlikely, but still.

 

[ZeusDriver]

Maybe. I think the hybrid Atkinson cycle engines are going to have a tough time supplying the truck in edge case conditions which is kind of why ford is in the situation it is in- the Lightning “failed” in fords eyes due to range collapse towing and in the cold.

if the go with a smallish hybrid engine then you will have a situation where you will be in a derated condition when towing grades. Edge case but important to theoretical buyers. I think if ford wants this to be a true towing machine then they have to have an engine able to supply the vast majority of power at peak demand.

if they actually build it- the genset will have to be substantial and will likely have multiple modes - standard output and a max output. To supply max output it may be better for a tuned turbo generator where it can produce massive power for heavy loads for short periods and standard output, likely somewhere out of boost, to just recharge the battery- out of boost. 2.7 would be perfect for this but packaging and price would be a nightmare. And at that point why not just build a traditional hybrid or small battery PHEV 2.7 that could have 40 miles or all electric range?

I don’t know if the economics work out but would be happily surprised to find out otherwise

On the back of an envelope, I looked at 14,000lb, 12% grade, 100 FPS = 305 hp for just the grade. So given aero, something around 500 hp should do the trick. A diligent driver (or an automated GPS- based system) would allow one to arrive at the base of the Rockies with a full charge (given a 130kW generator) . Hmmm: 100kWh pack, 400,000 Watts: 15 minutes range. Might want all the HV wiring to be water cooled, and you'd want to keep the generator running.

On the way back down wouldn't it be great if there were a way of using the drive motors to generate electricity!!?? Of course there is that darn aero drag -- works against you going uphill, and then works against you going downhill, putting energy into stirring air, that might be better put into your batteries... using my system, which I might call AgainGeneration, or BackAtYaGeneration... or how about RecuperationGeneration?

These edge cases certainly drive up costs. And in the current practical sense, the vehicles that will "solve" these cases (the RAM and Ford) are going to be incredibly expensive. A decade ago, I drove across the country in a minivan, towing a boat. I went quite slowly up long hills, with my eye on the temp gauge. Worked fine at 30 mph. The van, (which was solar-powered for its house batteries) was fun and reliable, and the slow speed towing was .0001 percent of its time on the road.

I think I will be looking at the RAM and new Ford from afar. My Volt was cheap to buy (slightly used) , cheap to drive, and very reliable. I even used it to tow part of my boat (about 800 lb trailering weight), and it did well, in spite of the fact that its tow rating was 0 lbs. If I find the need to tow my boat (the heavier part) for long distances, or if fast chargers become less reliable and harder to find (both minor annoyances now) the Silverado's range would work very well for me. Until then, even my SR lightning works really well. Could have been such an easy path into another Ford, if the range were like the Silverado.

 

[ZeusDriver]

I am going to find it hilarious when an EREV towing a camper exits the interstate, gets to the stoplight and the engine runs full throttle to try and catch up. I figure it's unlikely, but still.

My old Volt would occasionally do that. When commuting, the engine never started. If it did under normal circumstances passengers would not even notice -- it ran very quietly at low load. But for a long uphill pull, the engine was audible, and would continue to run fast for a while after.

 

[chriserx]

My old Volt would occasionally do that. When commuting, the engine never started. If it did under normal circumstances passengers would not even notice -- it ran very quietly at low load. But for a long uphill pull, the engine was audible, and would continue to run fast for a while after.

I figure exactly 2 people are going to be putting a loud aftermarket exhaust on a volt, one to see what's possible, and one for the lulz. The truck market though???

 

[ZeusDriver]

I figure exactly 2 people are going to be putting a loud aftermarket exhaust on a volt, one to see what's possible, and one for the lulz. The truck market though???

I'm thinking straight through (we don't need no stinkin mufflers) and two 4" chromed vertical slash cut stacks at the front of the bed. 6' from bed to tip seems right.

EDIT:

I'm tooling up to make the kit now! I'll send you half the profits.

 

[Mal106]

My PHEV Niros were '19 and are '23 obnoxiously loud when cold but when warmed or at speed, I have to look at the tach to know the engine is running. Transitions are seamless. My '23 Powerboost was not nearly as smooth or quiet.

Software can overcome a lot but if you HAVE TO have ICE power up a hill, your regen will be limited coming down. Even now with my truck, I wonder if it disables trailer brakes downhill so that regen is maximized. The YouTube towing videos don't seem to address that.

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