The number of energy conversions in EREVs is significant once the generator kicks in and each energy conversion step results in an efficiency loss. Here is what I see happening once that generator starts running:
Gasoline (chemical) energy converted to mechanical energy.
The gasoline is burned in the EREV's ICE to create mechanical (rotational) energy. Probably the biggest energy loss occurs here. Note that all ICE vehicles encounter this loss.
Mechanical energy converted to DC electrical energy
The crankshaft of the ICE is driving a generator to produce DC electrical energy.
DC electrical energy converted to chemical energy
The DC output of the generator is sent to the EREV's battery and converted to chemical energy.
Chemical energy converted to DC electrical energy
The EREV's battery converts the stored chemical energy back to DC electrical energy.
DC electrical energy converted to mechanical energy
The DC electrical energy released by the battery is converted to mechanical (rotational) energy via one or more electrical motors.
Note: The EREV may be designed to skip steps 3 and 4 if the generator's DC output bypasses the battery and is directed straight to the electric motors. I assume this is how a Diesel/Electric locomotive works. But, some portion of the output probably still must go to the Li-ION battery and a 12-volt battery.
Exactly the kind of modular I was thinking as example. I had a car once with half a V8, and some manufacturers have essentially taken two inline-six designs to make a V-12. Anyway, my Ford V-10 was rated up to 22,000 pounds GCWR in E-450 applications. My thought was that a 5-cylinder truck gas engine around 3.4 to 3.7 Liters would have been more economical all around; and still have plenty of power for the job.
Agree. When manufacturers were recently moving towards EVs as fast as possible, I can see how new engine development would have been halted. Maybe they will reconsider somewhat, particularly with hybrid-optimized engines. I read both GM and Ford were working on new inline-6 turbo engines that were canceled. Not implying these were necessarily for hybrids.
As far as Stellantis goes, I can’t relate at all wanting to buy any large vehicle with a 3L twin-turbo six making 500 HP. You’d have to almost give it to me. I know and accept that auto enthusiasts want or feel they need 500 HP, but I wonder how many actual buyers in the general public view vehicles that way. I’m more of the very opposite mindset wanting my cars follow the KISS principle. I prefer (liked) inline engines, naturally aspirated, and installed longitudinally. I say “liked” because I’m not sure that combination even exists today. I can’t recall any off the top of my head, at least no vehicle I’d be interested in buying.
Only thing I would add is that if Stellantis continues to have problems replacing Hemi V8 with Hurricane, it’s not because it’s a straight six. Hurricane happens to be a straight six, but that’s not the primary cause of their problems AFAIK.
Came here to say this as well, I see it's been discussed and I'm not really convinced, but I never did finish my engineering degree so...
Seems to me adding the cost and complexity and relatively low tq numbers of a DOHC v8 doesn't really make sense in a generator application. Smaller displacement godzilla or even one of the smaller ecoboost v6s with big tq numbers make more sense in my head, though that would add even more complexity and fuel consumption under heavy load with a turbo is tricky.
Honestly don't like these EREV things, seems like a lot of different crap to go wrong. It's a good stop gap measure, but I personally think they'll end up obsolete sooner than later as battery tech evolves. A superduty one does fit my personal use case right now though. 99% <100 miles a day towing ~10k with a couple big road trips towing several hundred miles per year.
At the time, the brief was to develop a new cyclone V6 engine that could be used in RWD and FWD applications.
The Cyclone V6 was justified because it allowed Mulally to kill off loads of other V6 designs from previous decades.
As we’ve discussed before, the cost of replacing the existing V6 with an I-5/I-6 design is either not justified or not
a priority for Ford otherwise it would be copying Stellantis right? So maybe it’s better to watch them brag about
their I-6 engine while they slowly go bankrupt.
I think what we are reading is mostly rumors and hearsay, so I wouldn’t get bogged down in details we don’t know at this point, or accuracy of their speculation. I was simply trying to show that concept could be made to work for many buyers.
We know that pickup trucks can easily triple energy consumption per mile when towing heavy and large trailers close to their max tow rating, whether gas, hybrid, or electric. IMO the speculated 120 miles of range when empty could turn to 40~50 miles when towing heavy. My guess is that many buyers who tow most of the time will stick with conventional powertrains for now. On the other hand, buyers who only occasionally tow and drive empty much of the time may love an EREV. It’s hard to say since we don’t even know the price premium.
When I was in school back in the dark ages of electrification, the mechanical engineering department built two hybrids with same EREV powertrain concept, and they both had similar issues. One was a city bus with a diesel generator, and it performed well given available technology of the time. What helped a lot was that average power consumption was very low due to low city speeds and time the bus was stopped. The other vehicle, a small passenger car, was not as competitive because of low powertrain efficiency compared to conventional cars.
I have mentioned this before, and this thread may be good place to repeat. Perhaps Ford can engineer a truck-specific transmission using the same concept as Honda’s two-motor design. It’s essentially the same concept we have been discussing for EREV, except the generator and drive motor can be connected directly by a clutch. As I understand it, the latest Honda system operates just like an EV at low speeds and once up to cruising speed, the clutch connects engine to wheels (through gear reduction of course).
Let's see what Stellantis does. The Ram EREV will beat the F-series EREV to market, so Stellantis engineers are struggling with the same problem, and have probably already come up with a solution.
I don't want to disparage the source of this comment, but I feel he may not be impartial.
I do not see other automakers following Ford's quest for Smaller EVs.
I think focusing on one aspect of the EV tech, is dangerous. The success of the Tesla and the Chinese is based on a holistic approach to EV development, there is a a lot of innovation happening with EV motors, inverters, Aerodynamics, packaging, and supply chains, to reduce costs and improve performance.
This is a neat snapshot of how Hyundai is approaching improved efficiency on large EVs