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It looks like the engine is the same and it's getting all the extra hp from the MGs front and rear. So I really feel that it shouldn't lose more than 1-2 MPG at the most due to additional weight from the larger battery pack and larger MGs. I'm I missing anything?
 

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It looks like the engine is the same and it's getting all the extra hp from the MGs front and rear. So I really feel that it shouldn't lose more than 1-2 MPG at the most due to additional weight from the larger battery pack and larger MGs. I'm I missing anything?
One change Toyota made to the Prius Prime was to add a one-way clutch to the transaxle. This allows MG1 to act as a traction motor when in EV mode. I'd speculate that they did the same thing to the RAV4 Prime. This change alone (along with a larger battery) would have made it a fine PHEV, with about 200 hp in electric-only mode. Of course, Toyota did even more and added another 100 hp -- to speculate further, all the additional hp comes from a stronger rear motor.

Anyway, my point is that this one-way clutch could add some resistance when in gas mode, lowering efficiency slightly. Though even that's hard to say, since the Prius Prime (when in hybrid mode) actually gets slightly better fuel economy than the Prius. The comparison is difficult because the Prius Prime has many other differences that are probably at play, but it's clear that the clutch can't be adding all that much resistance.

There's some reports that the gas engine has been modified slightly to have more torque at lower RPM. We don't know if this has any impact on the fuel economy.

Another thing to consider: a larger battery can also improve fuel economy, even if you never plug it in. There are certain situations when the current hybrid's battery can fill completely (long descents in the mountains, or warming up the car in the winter). IIRC, a battery charges most efficiently when in the middle of its operating capacity and less when full, so additional regenerative braking isn't as efficient. And if it's completely full then you lose any ability to recover energy. Though this is something of a specialized situation.

On the whole, though, I agree that the impact to efficiency will be minimal. For all we know, Toyota found another MPG or two to add!
 

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One change Toyota made to the Prius Prime was to add a one-way clutch to the transaxle. This allows MG1 to act as a traction motor when in EV mode. I'd speculate that they did the same thing to the RAV4 Prime. This change alone (along with a larger battery) would have made it a fine PHEV, with about 200 hp in electric-only mode. Of course, Toyota did even more and added another 100 hp -- to speculate further, all the additional hp comes from a stronger rear motor.

Anyway, my point is that this one-way clutch could add some resistance when in gas mode, lowering efficiency slightly. Though even that's hard to say, since the Prius Prime (when in hybrid mode) actually gets slightly better fuel economy than the Prius. The comparison is difficult because the Prius Prime has many other differences that are probably at play, but it's clear that the clutch can't be adding all that much resistance.

There's some reports that the gas engine has been modified slightly to have more torque at lower RPM. We don't know if this has any impact on the fuel economy.

Another thing to consider: a larger battery can also improve fuel economy, even if you never plug it in. There are certain situations when the current hybrid's battery can fill completely (long descents in the mountains, or warming up the car in the winter). IIRC, a battery charges most efficiently when in the middle of its operating capacity and less when full, so additional regenerative braking isn't as efficient. And if it's completely full then you lose any ability to recover energy. Though this is something of a specialized situation.

On the whole, though, I agree that the impact to efficiency will be minimal. For all we know, Toyota found another MPG or two to add!
The Alex on Autos video says that at least the XSE has wider ties as well, so that could also affect MPG.
 

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The Alex on Autos video says that at least the XSE has wider ties as well, so that could also affect MPG.
He said the XSE has 235 width tires which is the same as the 4th gen Limited HV and gas(235-55-18) as well as the 5th gen XLE Premium and up gas models(235-55-19).
 

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That’s accurate - the regenerative braking is reduced if you’re state of charge is too high. This is why it is suggested that unless you know you need the range, just top off around 80% max. Batteries seem like they are the happiest as close to the 50th percent mark as you can get but it’s diminishing returns to a point.

In other words if you use 20% per day, charging to 60 and running to 40 would be “nearly ideal” but it’s not as big of a difference in terms of degradation compared to someone that constantly charges to 100% daily.

there are also typically hidden buffers to help protect the battery, meaning 100% might truly only be 90 or 95% to protect the top end and likewise 0% might really be 5% or 10%.
 

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Model Y is ahead of schedule for Q1 will probably steal a few sales from Rav4 Prime, which may also mean better pricing/deals/availability


 

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Doesn't matter even if it is 5-10 mpg worse then hybrid, you still have 39 miles of electric range which for daily commute is plenty for most
Well it MAY matter. If you do a lot of lengthy trips a 10mpg difference will add up. Unless you are able to and plan to charge the Prime regularly, the regular Hybrid may be a better buy. And we don't know yet how and under what conditions that 302hp in the Prime will be usable. If all that power is there on demand I would agree that the 5-10mpg hit matters less.
 

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Well it MAY matter. If you do a lot of lengthy trips a 10mpg difference will add up. Unless you are able to and plan to charge the Prime regularly, the regular Hybrid may be a better buy. And we don't know yet how and under what conditions that 302hp in the Prime will be usable. If all that power is there on demand I would agree that the 5-10mpg hit matters less.
Well and I said to "most"... but it's a safe bet it won't be 10 mpg difference maybe somewhere 2-4. Besides if you do care with a lot of lengthy trips then why not go with a Prius, it's already 10 mpg better then Rav4h so it should matter and even has AWD....
 

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Well and I said to "most"... but it's a safe bet it won't be 10 mpg difference maybe somewhere 2-4. Besides if you do care with a lot of lengthy trips then why not go with a Prius, it's already 10 mpg better then Rav4h so it should matter and even has AWD....
2-4mpg is nothing, I agree. As for switching to the Prius, Little Car World and Compact SUV Worlds don't collide...
 

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No, it's not a matter of what you happen to owe at the end of the year. It's your total federal income tax liability for the tax year, no matter when you paid it. For example, if based on your income you are liable for $8,000 in federal income tax for 2019, and you happened to pay all of it through withholding during the year, so that absent the EV credit your tax return balance would be zero, adding the credit will get you a check from the feds for the $7,500 credit. If you only paid $2,000 of the $8,000 in withholding, then instead of owing $6,000 on your return you will get a check for $1,500. HOWEVER, if your total federal tax liability for the year was $4,000, that will be maximum EV credit that you will get, but what you get when you file your return will depend on how much of that $4,000 you paid during the tax year.

Ah, well put! So, its as simple as looking at my last pay stub for this year and confirming the Federal Withholding that i had for the year. If it's at least 7,500, i can expect the full fed rebate? I typically don't owe at the end of the year. If anything, i owe a bit more. In fact, this year i have already paid over 10k so i should be good next year assuming this vehicle qualifies for the max rebate. I don't think I'm missing anything?
 

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And we don't know yet how and under what conditions that 302hp in the Prime will be usable. If all that power is there on demand I would agree that the 5-10mpg hit matters less.
I am also very curious under which circumstances maximum acceleration will be possible. Is anyone aware of performance degradation for the regular hybrid based on charge level? I did some quick searching and was unable to find any information.

Based on the info below from a discussion with Toyota reps at the Prime launch I suspect you will only get your 302 HP in HV mode. Altering the power band of the gas engine to allow for more power at lower RPMs seems like it was done in the name of "performance". So it looks like when you are using your 39 miles of EV range you probably won't have access to all 302 HP. But once in HV mode it would appear you can stoplight drag race until your heart's content, fuel economy be damned.

"The RAV4 Prime shares the same 2.5-liter Atkinson-cycle four-cylinder as the regular RAV4 Hybrid, but it's tuned differently. Its 176 horsepower is the same, but it produces 168 pound-feet of torque at 2,800 rpm versus 163 lb-ft at 3,600-5,200 rpm. Toyota says that greater grunt in addition to more powerful electric motors means you'll be able to notice a definite difference in low-speed driving. The fact that the Prime is a full two seconds quicker from 0-60 would certainly back that up"

reference: https://www.autoblog.com/2019/11/20/2021-toyota-rav4-prime-revealed/
 

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If they manage to cripple performance when battery depleted (when every other phev does not have that limitation) then I think my choice would fall onto Model Y.
Citation needed on "every other phev" not having this limitation.

Here's examples of three popular plug-in hybrids, each using different hybrid systems (series, parallel, and series-parallel).

The Volt is a series hybrid. It has a 149 hp electric motor, but the gas engine used for range extension only produces 84 hp 101 hp. Thus, when the battery is completely depleted the maximum power you can get is only 84 hp (44% reduction) 101 hp (32% reduction).

The Iconiq is a parallel hybrid. Its gas engine produces 104 hp, and the electric motor produces 60 hp. Combined, the two produce 139 hp. When the battery is completely depleted, the maximum power you can get is only 104 hp (25% reduction).

The Prius Prime is a series-parallel hybrid. Its gas engine is 95 hp and the electric motor is 70. When combined, the peak power is 121 hp. When the battery is completely depleted, the maximum power you can get is only 95 hp (21% reduction).

The RAV4 Hybrid should also be mentioned, and works like the Prius but with a second electric motor. The gas engine is 176 hp, the front electric motor provides 118 hp, and the rear is 54 hp. Combined, they produce 219 hp. When the battery is completely depleted, the maximum power you can get is only 176 hp (20% reduction).

No matter what the hybrid, you'll see a reduction in power once the battery gets low enough. This is a physical necessity of a hybrid: the whole point is to combine the best features of two different power trains. Each has its advantages under certain situations -- and there's a certain amount of overlap between the two. This overlap means you can combine them to get even more power than either alone. But take away the battery, and now you're limited to only what one can provide. Performance is limited.

But here's the thing: the battery has to be completely discharged, or at least below a certain level. As long as the gas engine and regenerative braking can keep up, you won't deplete the battery to the point that performance will suffer. For this to be a problem, you have to be exceeding the ability of the gas engine to recharge the battery. That means constantly exceeding the power output of the gas engine alone (otherwise the excess could be used to charge, buffering for the next burst of power).

When would this theoretically happen? Climbing a mountain pass might do it, especially if you're towing or with lots of cargo. Or maybe constantly ping-ponging between 0 and 80 mph. So, it should be possible if someone wanted to do it. The Volt actually has a special driving mode just to account for this: in "Mountain Mode" it will be more aggressive about charging the battery so that you still have power when climbing. I don't think other hybrids do this: maybe it's because the Volt sees such a significant drop in power compared to the others.

The RAV4 Prime will certainly see this problem a bit more distinctly than the RAV4 Hybrid, though, I'll give you that. The gas engine is still only 176 hp, which means a 42% reduction in peak power if the battery gets low enough (note: still less than the first-generation Volt). And being a car with significantly more cargo capacity, one you might actually try to tow with, maybe it's more likely people will drain the battery to this point? Maybe they'll also add a mountain mode?

And lest we forget, EVs have this same problem. You know how much power they're able to produce when the battery is drained? 0 hp.

(Edited to correct Volt horsepower.)
 

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Citation needed on "every other phev" not having this limitation.

Here's examples of three popular plug-in hybrids, each using different hybrid systems (series, parallel, and series-parallel).

The Volt is a series hybrid. It has a 149 hp electric motor, but the gas engine used for range extension only produces 84 hp. Thus, when the battery is completely depleted the maximum power you can get is only 84 hp (44% reduction).
The G2 Volt actually has a 101hp range extender. The 84hp is the old G1 model.
 

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The G2 Volt actually has a 101hp range extender. The 84hp is the old G1 model.
Thanks for the correction. For completeness, that's a 32% drop in performance when the battery is too low.

I do wonder if the RAV4 Prime will get a mountain mode. It would certainly see a significant drop in power in that condition. On the other hand, it'll perform similar to the RAV4 Hybrid, which seems to do fine -- you might not get full performance, but it still has enough oomph anyway.
 

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Citation needed on "every other phev" not having this limitation.

Here's examples of three popular plug-in hybrids, each using different hybrid systems (series, parallel, and series-parallel).

The Volt is a series hybrid. It has a 149 hp electric motor, but the gas engine used for range extension only produces 84 hp. Thus, when the battery is completely depleted the maximum power you can get is only 84 hp (44% reduction).

The Iconiq is a parallel hybrid. Its gas engine produces 104 hp, and the electric motor produces 60 hp. Combined, the two produce 139 hp. When the battery is completely depleted, the maximum power you can get is only 104 hp (25% reduction).

The Prius Prime is a series-parallel hybrid. Its gas engine is 95 hp and the electric motor is 70. When combined, the peak power is 121 hp. When the battery is completely depleted, the maximum power you can get is only 95 hp (21% reduction).

The RAV4 Hybrid should also be mentioned, and works like the Prius but with a second electric motor. The gas engine is 176 hp, the front electric motor provides 118 hp, and the rear is 54 hp. Combined, they produce 219 hp. When the battery is completely depleted, the maximum power you can get is only 176 hp (20% reduction).

No matter what the hybrid, you'll see a reduction in power once the battery gets low enough. This is a physical necessity of a hybrid: the whole point is to combine the best features of two different power trains. Each has its advantages under certain situations -- and there's a certain amount of overlap between the two. This overlap means you can combine them to get even more power than either alone. But take away the battery, and now you're limited to only what one can provide. Performance is limited.

But here's the thing: the battery has to be completely discharged, or at least below a certain level. As long as the gas engine and regenerative braking can keep up, you won't deplete the battery to the point that performance will suffer. For this to be a problem, you have to be exceeding the ability of the gas engine to recharge the battery. That means constantly exceeding the power output of the gas engine alone (otherwise the excess could be used to charge, buffering for the next burst of power).

When would this theoretically happen? Climbing a mountain pass might do it, especially if you're towing or with lots of cargo. Or maybe constantly ping-ponging between 0 and 80 mph. So, it should be possible if someone wanted to do it. The Volt actually has a special driving mode just to account for this: in "Mountain Mode" it will be more aggressive about charging the battery so that you still have power when climbing. I don't think other hybrids do this: maybe it's because the Volt sees such a significant drop in power compared to the others.

The RAV4 Prime will certainly see this problem a bit more distinctly than the RAV4 Hybrid, though, I'll give you that. The gas engine is still only 176 hp, which means a 42% reduction in peak power if the battery gets low enough (note: still less than the Volt). And being a car with significantly more cargo capacity, one you might actually try to tow with, maybe it's more likely people will drain the battery to this point? Maybe they'll also add a mountain mode?

And lest we forget, EVs have this same problem. You know how much power they're able to produce when the battery is drained? 0 hp.
44% reduction on Volt? Where are you getting these numbers and what do they really mean for 0-60?

 

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Thanks for the correction. For completeness, that's a 32% drop in performance when the battery is too low.

I do wonder if the RAV4 Prime will get a mountain mode. It would certainly see a significant drop in power in that condition. On the other hand, it'll perform similar to the RAV4 Hybrid, which seems to do fine -- you might not get full performance, but it still has enough oomph anyway.
I can't speak for the Prius Prime or Ioniq PHEV, but our G2 Volt, even with battery fully depleted. It drives nearly identical aside for the slight ICE hum. It'll still merge safely onto any busy highway and happily maintain 80mph on the freeway with a fairly loaded car.
 
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