How the iForce MAX system works (Toyota video)

You're confusing this style of hybrid system with Toyota's other hybrid system. The iForce Max looks to just use a motor generator unit. This means the motor is the generator and vice versa. It's either in one mode or the other: deploying electrical energy to mechanically supplement engine power or regenerating and charging the hybrid system battery. It's not constantly charging, it's charging during coasting or decel by harvesting vehicle kinetic energy and probably sometimes by siphoning off engine output if battery charge is too low. Toyota calls this a parallel hybrid system.

Other Toyota hybrid systems use a seperate motor and generator and the generator is just used to charge a battery using only engine output as needed via a power split device. The mechanical regen in these systems comes back through that separate motor (acting as another generator). In these cases you can think of the standalone generator as a kind of alternator-on-demand. These systems are used where vehicle drive is meant to be more heavily electric and electric only at times. Toyota calls this a full hybrid system.

 

This hybrid system increases max power output (engine and motor combined is more than engine alone) and increases fuel efficiency (waste energy can be harvested and used again and where the engine is inefficient the motor can help).

It's really that simple. The implementation is the complex and expensive part.

 

People on here for year wanted these trucks with more power output and Toyota delivered and now they're complaining on the method of how it's done. Weirdos.

 

It doesn't take 48 HP from the engine to create the electricity needed to drive the 48 HP motor. That's why cars have electric fans and power steering. It's more efficient to create the electricity from the alternator/generator and power the electric motors than it is to pull the power directly from the engine (mechanical fan and hydraulic steering). And the battery can also be recharged with otherwise wasted energy in regenerative braking.

 

If you’re doing the hypothetical full throttle pull at max rpm for extended periods, it absolutely will require the same amount of power. we get away with it in normal driving by extending the time frame in which the battery charges, but if you run out of reserve, you don’t get free kW, and a 48hp (~36kW) electric motor will still take 48hp to drive in “real time.

now, it gets fun because in normal driving you add a time element, batteries are rated in kWh (kilowatt-hours), and so you’d need to figure out the horsepower-hours it takes from the ICE side to charge it. So 5hp taken during a 30 minute drive might give you 2.5hp-h, or
1.86kWh (the capacity of this hybrid battery) that can all be used as 48hp (36kW) over just a few minutes. That works great in all but the most insane circumstances (which were posited by others when we started this chain).


electric power steering and fans save energy by being right sized for demand and not needing to be oversized for low RPM use.

 

Bingo....they are actually less efficient in a like for like situation (which you'll never have) but on average they prove to be more efficient because they are variable speed and can ramp up to meet demand when needed or be used pretty much not at all when cruising.

The reality is energy can't be created or destroyed. Which means if the energy came from the engine while maintaining speed or accelerating, it ain't free. You burned fuel to get it. The only free energy (that would otherwise be wasted) is under braking or coasting down hill. And any time you transform kinetic energy to electrical potential energy (or the reverse) you waste some of it.

Ultimately, I think a lot of people are pumped up about the addition of more power. And they should be. We've been dealing with fairly anemic V6s for quite a while in these trucks. But I think the disappointment for some buyers is seeing the implementation of a "hybrid" system and realizing it really won't get any better mileage than the NA V6....which is indeed disappointing because the Achilles heel of the 2nd and 3rd gens is the fuel economy. My range, with 34" tires and a 3" lift, is about 250 miles per tank. It's a real pain in the ass on long trips. So while this new truck has a "hybrid" option it's really just a power boost. But I guess Ford already trademarked that name.

 

I think we will still see pretty significant real world improvements in MPG for those of us who swing big tires and/or carry gear a lot, just due to the fact that the torque will be there at lower RPM so there will be less winging the motor out in city driving.

 

In city driving where stop and go is a lot...yes. But on the highway it's not going to change much. The turbo 4 alone will be the biggest factor there.

Call me crazy, but I feel like active aero or air bag suspension (with variable ride height) would have been less tedious from an engineering perspective and yielded more highway fuel economy. If you could drop the truck 2-3" on the highway you'll see a bigger improvement from that than pretty much anything else.

 

Oh there are lots of ways to improve MPG on the Tacoma sized trucks.
But watch this forum explode with rage if you implement any of them. See the chin spoiler, for instance

 

"iF u WaNtEd MpGs U sHuDDa bOuGht a cAmRY"

My own personal opinion....for what it's worth. I'm just happy to see them finally innovating again. The 3rd gen was a HUGE disappointment because it was just a more expensive 2nd gen in different clothes.

 

The on demand part for an electric fan/power steering is absolutely another way to save power. However, even both at full load, it's more efficient to run an efan than a mechanical. The process of creating the electricity (alternator) need will draw more power. An alternator takes about 7-8 HP at full load with a solid portion of that going to drive the efan at full power. So that efan is drawing most of that 7-8 HP.

A mechanical fan at full load will require nearly 4 times as much hp to drive it. This is a snapshot from the Engine Masters episode where they tested mechanical fans. It's a great show if you've never watched it. They also test a mechanical vs electric water pump. And again the electric is more efficient even accounting for the extra load on the alternator. Not nearly as big as the fan though.

 

Yes, because the mechanical fan needs to be oversized for low RPM use. So it’s not efficient at high RPM. flex fans and clutches help but aren’t as good generally (though they can fail to work as well as mechanicals at high loads and low speeds). It’s all a balancing act of efficiency. In that engine master’s episode, the mechanical fan takes more power because it’s doing more work at top RPM than the electric fan is. It’s moving dramatically more air.

But the power draw to drive an electric motor is kw-h no matter how you slice it. If you want 36kW constantly, your engine is going to supply 36kW to the electric motor. That would require 48hp into a generator to run constantly.

luckily in all but the most insane circumstances, it doesn’t need to produce 48hp constantly.

 

Fair points. The more I think about this you have to be right. Just doesn't seem to compute in my simple brain.