Prius Plug-in and Volt Pros and Cons

PiP was supposed to launch with Gen3. They ran into battery production cost issue and delayed it 2 years.

Gen3 was designed with plugin in mind. Toyota started testing PHV in 2008 using Gen2.

The thresholds set were designed/balanced the efficiency of both fuels to achieve synergy. It is not "limited" because it is per design to achieve greater goal.

 

That information has been provided a number of times now. It hasn't done any good. The history just keeps getting spun and the belittlingly continues. Like I said, at least that serves as a gauge.

Away from that nonsense, I'm enjoying my PiP. Today, it was a round-trip through the heart of rush-hour congestion territory. It was 19.5 miles each way. We escaped the meeting just prior to afternoon rush kicking it. Since I wasn't alone, I took advantage of the carpool lane. Rarely ever having reason to be in that area of the cities during that day of the time, why not try it? Long story short, there was a little bit of stop & slow followed by a nice highway cruise. Having started the trip with only 1.3 miles of EV available, it was almost entirely hybrid operation. I was delighted with the results... 60 MPG on the way there and 61 MPG on the way back.

So for those who sincerely aren't aware of the potential the system offers, that's a nice real-world sample of what's possible even with very little plug-supplied electricity available. For those who continue to spin, mislead, and downplay, they can kiss my gas.

As for the delay of PiP rollout, it should be clear why. The battery-cost & greenwashing should make that quite obvious. There are other barriers too. People simply have no background or basis of comparison available for making the purchase decision. That education takes time. Just look at how many assumptions continue to come out of the initial rollout states. To make matters more difficult, we even have some EV supporters working against acceptance, despite the fact that Prius can have a major influence on the advancement of plug-in batteries.

Toyota really did their homework to deliver a system able to reach the masses. So what if we have to deal with a few sour grapes. Owners are pleased with their choice. They didn't have to sacrifice seating or room for large cargo. They still get fantastic efficiency even when the battery is depleted. They purchased reliable hybrid with a plug. It's a winning formula for high-volume profitable sales. That upsets a few individuals, which is why we have to deal with their on-going banter.

 

My head spins from reading this thread, no one wants to believe what the PIP can do but the owners. As an owner of a new 2014 PIP, I'll chime in. I went to the local dealership to get advice on what to look for in a used early regular Gen 3. The salesman was great, then he said 'Hey, what about a new PIP?' I said I have no where to charge most of the week (I live on my boat), so what's the point?' He said, "A lot of my customers just charge once a week and don't drive in Ev Only mode and routinely get about 65mpg.' I said "STFU' I didn't believe him but bought the car anyway because I got it for $1200 under invoice, the lease interest was $18.56 for 3 years (that's right, under 20 bucks), I got 4k in rebates plus Toyota threw in another 1500. I drove the car and lo and behold the salesman wasn't jerking my chain. I live near Los Angeles. Climate is warm. I charge about once a week, drive carefully, a semi-hypermiler and routinely get 62-65mpg. I know no one that can do that in a regular Prius. In a Volt, faggetaboutit. Could care less if anyone believes me. Like John170a says, 'Kiss my Gas!'. I love this car! I make a lot of 100 mile+ trips and find that if I leave with a full battery I do better staying in HV mode the whole time rather than using up the EV in the city and then switching to EV.

 

Yep, anecdotal verification of just how efficient the PiPs really are could be a powerful determinant in helping convince a prospective buyer. My wife and I recently drove to a restaurant on Bailey Island here in Maine, a 60 mile round trip. The trip there used 8 EV miles of the starting 16 mile full charge before I switched to HV mode. Country roads allowed me to keep speeds under 50 so I was able to remain on the EV side of the EV/HV display much of the time for the full round trip. MPG indicated upon arrival at the restaurant was 108. Pretty much the same returning home but I mis-judged just when to return to pure EV to try to use the remaining 8 plug-in miles. Still had 2 remaining at the driveway for an indicated MPG of 88, which included clawing up an incredibly steep hill in Freeport - no problem for the car but I knew I was sucking way more gas than I usually allow. The PiP, as I've said before, is a lovely little car. And the headlights that evening were more than adequate!

 

Probably not. Acceleration and speed are mostly limited by the power output capability of a 4.4 kWh Lithium Ion battery pack that can fit under the hatchback floor.

They have a 60 kW motor but cannot drive all of its capability from the battery which is only good for a peak output of around 37 kW. That's just a function of battery size. If they had a 7.6 kWh pack like the Ford Energi then they could output the full 60 kW (I recall that Ford will use up to around 67 kw).

The Volt, with 16.5 kWh, can output around 111 kW and the same pack puts out a little extra in the ELR. The Tesla with 85 kWh can put out 310 kW.

 

I had a PIP for 18 months, IMO it had plenty of get-up-and-go. There is a certain uphill while accelerating section of my daily commute that would sometimes cause the ICE to kick in if I didn't keep a close eye on the power meter- but if traffic flow required- I could just step on the gas and get additional power from the ICE. Again, no shortage of power- just not that much in EV only mode.

The simple/accurate work around in the PIP is to reset trip odo B at the beginning of each month, by the end of the month it shows you exactly how many miles were ICE and how many were EV- just keep a running total from month to month and you'll have accurate oil use info.

With the warmer weather I'm up to 45-48 miles estimated EV range now. If I drive the slower scenic route home from work- I'm actually getting a tad over 50 real miles (not estimated) in EV mode.

 

That's a very good point. In a regular vehicle, the energy that goes into acceleration and braking is lost, so it stands to reason that a heavier vehicle is wasting more energy, and is less efficient. But in a hybrid, at least a portion of that energy is recovered through regenerative braking.

It still doesn't compute that a heavier hybrid car has any advantage over a lighter one however; even if regeneration could recover 100% of the energy lost, it would still be a wash. As it stands, the process is only about 31-33% efficient, therefore the lighter hybrid should still get the better mileage.

 

The hell you don't, what about the Bill Norton brand ?

 

Ever notice that electricity is generated while you drive, not just when touching the brake pedal?

Ever consider that the software in the plug-in model is different from that in the regular?

Ever get tired of having to prove something with an on-paper absolute rather than just accepting real-world results... even if they are counter-intuitive?

It's just nice knowing the system is somehow achieving gain... even if we can't pinpoint why.

 

The lowest regen braking efficiency number I've seen for a modern plugin car was 39%, supposedly in a LEAF manual, but this may have included braking averages that included harder stops that included friction braking. I've seen some estimates that the conventional Prius averages in the low 30%'s but this may be due to limitations on how much power it's smaller non-plug hybrid battery can absorb (20-30 kW). A car with a larger battery like the Volt or Model S can regen at 60 kW at highway speeds.

More typically, I see estimates ranging from 50-80%. For example, this article includes a deceleration (speed limited) vs. regen efficiency chart (shown below the link) for the Chevy Volt showing efficiencies around 50-75% during regen deceleration that would be seen at highway and faster city street speeds. The regen deceleration and kW power regenerated is higher at faster speeds.

Braking deceleration of about 0.2-0.3g is the maximum regen braking for the Volt and is also around the point at which government regulations begin to require the brake lights to be illuminated.

Design News - News - Chevy Volt Tech Watch: Regenerative Braking

 

Well, I can't say I've noticed that, and I've been studying things pretty closely. The only time I see the battery being charged is when I am coasting or braking.

If you think about it, the least efficient way to use the fuel would be for the gas engine to charge the battery, and then use the battery to drive the electric motor to drive the car. The Prius seems to have been designed to avoid charging the battery with the engine in any way.

Of course the gas engine and generator should kick-in to rescue the battery from going into too deep a discharge state, but I've never seen it happen. In a different thread, someone described how they connected a large inverter to the hybrid traction battery, and the engine/generator kicked-in and kept it charged. I have no reason to doubt it's true.

 

Good job, Bill. Never be loyal to something that doesn't love you back, I say.

 

Not sure how you picked up on those misconceptions, but they are quite common.

Prius generates electricity 100% of the time the engine is providing propulsion. The "magic" comes from directing that electricity to be used most effectively. Sometimes it's for propulsion. Sometimes it's for recharging. Sometimes it's for both propulsion & recharging.

Watch the Energy display. You'll see that electricity being routed in a variety of different ways and changing quite frequently. That is the PSD in action. It splits power to squeeze out the most of the multiple fuels available.

 

I wouldn't put much stock in the animated display. If you research the Prius hybrid system, it's definitely not burning much fuel charging the battery. The battery is there to capture lost energy from coasting and braking.

 

I think that there is a terminology issue here. What IS true is that the ICE in the PiP is not used for the purpose of charging the battery outside a narrow HV range. This range may not be the depleted SOC (state of charge); you can go into HV mode with battery remaining, and the current SOC will become the new HV target. But the ICE is not going to run just to recharge the battery so you can resume EV mode. Of course, one can play games with this. One can use HV to climb a long hill, switch to EV mode going down the hill, and then at the bottom of the hill, toggle EV/HV to establish a new HV set point. So, the ICE (which powered the car up the hill) provides the energy (via regeneration down the hill) to recharge the battery.

 

What may have been forgotten is that the ICE is coupled directly to the drive-train through a clutch for most of the time while driving. The only time the vehicle is being powered electric-only, is at slower speeds, and in EV mode.

When more power is needed during acceleration, the electric motor helps out (as in Hybrid Synergy Drive) so it stands to reason that as the hybrid battery is being drained, that power would come from the ICE to charge the battery.

 

The system does not have a clutch for the engine. All propulsion power is directed through the RING carrier, which is what MG2 (the 60 kW electric motor) powers. The PLANETS are what connects the gas engine. Balancing that out is the SUN, which is MG1 (the other electric motor). It spins and holds when power is directly in different paths, known as power-splitting.

I strongly recommend getting an aftermarket gauge to allow you to see this taking place firsthand. A good start to better understanding would be to watch this video. It shows the engine and 2 motors interacting...

 

I stand corrected. The two electric motors counteract with each other to achieve zero RPM for the ICE.

 

The system uses a Power-Split-Device, which is quite different from any type of transmission for cars anyone used to call. There isn't nothing that disconnects. There are only power carriers, that are always in contact with each other.