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Old 04-19-2016, 06:53 AM   #21
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Originally Posted by 14Corolla View Post
It must be very interesting to drive that Prius. I'm presuming it's automatic, how much the electric and gas are used? You don't have manual control over that?
If the hybrid doesn't have a plug, all its energy is coming from gas. The electric side of the system allows the reduction of the penalties from wasteful behavior in a standard ICE car; turning the engine completely off when not in use, giving a boost during acceleration, recapturing some of the energy lost from braking, etc. The input of the motor also allows the ICE the be downsized; using one with the right power output to be efficient while cruising, and not have a high hp overhead for the few times of heavy acceleration seen during a daily drive.

The Prius' great fuel economy starts with the efficient ICE. The Atkinson cycle it uses increases the fuel efficiency at the expanse of power compared to the same sized engine block used in the Corolla. Much of the efficiency improvements to the past couple of models was due to improvements to the ICE; the latest one has a 40% thermal efficiency. Approaching diesel territory, and it likely could go higher if Toyota didn't want the super ultra low emissions. Improvements to the electric side include some efficiency ones, but mostly been aimed at cost reduction.

tl;dr Hybrids get great fuel economy because they have a dog of an engine. The electric side just makes the car's performance something people are willing to drive.

Ben covered the EV button. With the battery charged only by the ICE, over use of it can actually reduce your overall fuel economy.

Toyota makes good, dependable cars. Most of their models tend to be on the appliance side of driving excitement though.


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Originally Posted by benlovesgoddess View Post
Keyless entry and start button a treat, heated seats and dual climate the wife loves (bizarrely, an animated Prius driving over a hill when you start pleases her a lot too).
Have you tried opening your house door and wondered why it didn't simply unlock on its own for you yet? Smart keys are a great convenience. Saved my but from locking myself out once. I just don't value it enough to be a must have.
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I am open for any better instructions from long term Prius owners, but the best way to maximise electric use seems to be accelerating hard to say 60-70 mph (gas), then foot off and rolling down to 45-50 (recharging battery), then catching the accelelor lightly and cruising along in electric for as long as it holds, then repeating (Road conditions/other users allowing).
Try skipping the rolling down part. A fixed portion, around 27%, of the ICE's torque is always going to M/G 1. That could provide enough juice for recharging the battery during your acceleration pulse. For efficiency, you want to avoid taking energy out of the battery and putting it back in. There are losses in taking the kinetic energy from the ICE and brakes and converting it to electrical, then chemical, and back again.

Up to about 45mph or so in the gen2 Prius, you could feather the accelerator to get into a true glide; this is when the ICE is off, and no energy is coming out of or into the battery. The speed at which this is possible has increased with the newer models.

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Oh yeah, it is CVT auto.
Toyota's, and Ford's hybrids are actually an eCVT, which is just the short way of saying they act like a CVT. Their hybrid transaxles are just a single planetary gear set. The ICE and M/G1(motor/generator) input to it. Along with acting as the starter and generator, the system controls M/G1's input with that of the ICE's to simulate the variable gears of a traditional CVT.

M/G2 is the larger traction motor. It inputs to the outside ring gear, or further along the drivetrain, depending on who's system you are looking at.

GM's Voltec system is also a planetary gear set eCVT, but I'm familiar enough with it to say how close it is to Toyota/Ford. Honda's two motor hybrid in the Accord is also an eCVT, but it is just a chain of fixed gears between the motor and drive axle, that the ICE can clutch into at highway speeds.

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Originally Posted by benlovesgoddess View Post
We got in, loved the interior (the white trim seems unpopular in forums, I think it's great!). Walked around it - loved the exterior. I think it looks nothing like a Prius! Test drive immediately - loved the comfort, handling, gadgetry. As the Hyundai was in the doghouse, I was ready to switch then and there - dependant on not having to wait till August! So I got the showroom car.
Never liked Lexus - just makes me think Alan Partridge! Do I wish I d looked at the Mitsubishi PHEV? Maybe, but I doubt it would have driven as nicely, doesn't look as nice, and probably 10,000 more expensive!
I had a gen2 Prius, which was about the only hybrid in town at the time. It was a Toyota driving appliance, and the hybrid system still had some quirks to be ironed out, but the only real complaint I had was that it had the same uncomfortable seats as our Matrix. Still a great, all around car.

Sounds like the gen4 really improves upon the fun to drive factor. I have yet to see one in person, but the styling is more striking. I was happy to see the flying bridge of the gen3 go. The worry with the white is how well will it hold up over time. It does not go with the beige interior, which isn't offered in Japan, though. I'm concerned the shifter might be too low, but I'm mostly disappointed in the loss of the upper glove box, and other storage nooks in the front. I would also prefer some space under the cargo floor for jumper cables and the like instead of having the voids filled in with foam.

The Outlander PHEV has been a big hit for Mitsu, but it's North American intro keeps getting pushed back.

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Originally Posted by benlovesgoddess View Post
That photo hadn't loaded before I replied - it is a pretty saloon! Does it have the exact same hybrid with EV as the Prius, or just IMA style hybrid - what does it get to the gallon?
We don't get the IS hybrid, but sounds like the same hybrid drivetrain as in the Camry, Avalon, and ES ones. I think it is also the one in the Rav4 and NX hybrids.

It is older than the new Prius, so it won't see those improvements until later, but the larger ICE is the main difference.
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Old 04-19-2016, 10:35 AM   #22
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Cheers trollbait, comprehensive reply! I will see if I can practice your tips tomorrow.
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Old 04-22-2016, 04:11 PM   #23
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Looked at my cars dash, my last fuel up registers as 63.2 MPG, but when I scroll down to the table where all fuel ups are listed, my last fuel up is showing up as 63.15 MPG. Not sure if that would mess things up, but worth noting as it's obviously a different calculation.
We use different rounding precision in different places. I can't tell you why as it has been that way since I took over but all of the data originates from the same source, it is rounded on display.
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Old 04-22-2016, 05:10 PM   #24
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Ok thanks for the reply. Just wanted to make sure you guys knew about it, and that it wasn't messing up any data further down the line for anyone
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Old 04-23-2016, 03:28 PM   #25
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After reading through this.
That Prius doesn't have that much of battery. Does it?
Must be less than a golf cart? Much less?

I can see the brilliance in this Prius.
Charges when going downhill. Helps uphill.
Charges when coasting to a stop. Helps when accelerating.
More like it's a kinetic energy storage device.
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Old 04-25-2016, 06:15 AM   #26
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Originally Posted by 14Corolla View Post
After reading through this.
That Prius doesn't have that much of battery. Does it?
Must be less than a golf cart? Much less?

I can see the brilliance in this Prius.
Charges when going downhill. Helps uphill.
Charges when coasting to a stop. Helps when accelerating.
More like it's a kinetic energy storage device.
Precisely.

Hybrids are, at their heart, still an ICE powered car. The non-ICE side doesn't even have to be electric. Plenty of work has been done with hydraulic hybrids.

Along with using recaptured energy to help later on, a hybrid can also run the ICE at a higher, efficient load at the times a straight ICE car would be only running at a low, inefficient load. The excess energy produced gets stored in the battery or accumulator for use later.

Along with allowing the use of engine off modes, the fuel economy of the hybrid can be further improved by engine downsizing. A straight ICE car needs an engine sized to provide heavy acceleration and the ability to climb steep grades. This means giving up efficiency at the engine loads where the car will spend most of its time; light acceleration and cruising.

The help the hybrid side can provide means that it can provide the power for climbing and acceleration during those shorter periods. Letting the car designers put in a lower powered engine that is most efficient for the majority of the drive.
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