How will the Chevrolet Volt be better than a Toyota Prius plug-in hybrid?

Well that's why i say Volt has to avoid running it's ICE at all costs. The prius when cold emits less than the Volt when warm. GM decided to fit a crap ICE in the Volt, and the cost is that you can't use it even when it would be more efficient given the current user power/heat demands.

 

Volt still has worse evaporative emission when the ICE is not running. Volt also has to empty the tank once a year, if not used. It is called fuel maintenance. Engine maintenance will also run the ICE once every 6 weeks. So don't downplay Volt's cold start emission and evaporative emission.

Prius' cold start differs from a non-hybrid due to 1) clean Atkinson cycle and 2) unique -10 deg IGN combustion timing. Prius also has the exhaust heat recovery system that recover excessive heat to speed up the warm up process, reduce emission and keep the gas engine warm longer.

Volt has none of those to my knowledge. It has the same substandard Otto cycle without any heat recovery system. Tests have even shown that it has an anemic heater / preconditioning feature that resulted in gas engine running below 25 deg F.

 

That isn't entirely accurate. The fuel system is pressurized and it can sense both fuel quality and quantity. It does have a maintenance mode as you point out -- if the fuel is stale-- to draw down some of the older gas in the tank but it lasts for minutes. In the event the fuel is extremely stale, it may require more maintenance but again, the software handles this and guides the driver through the best approach to resolve the issue.

One long trip over range and the maintenance is a non-issue. Interestingly, the car is designed to function with no gas in the tank (they point this out!) So perhaps they assume people will do a few run dry trips to keep things fresh.

That being said, to your point, something for them to work on (the ICE emissions aren't great but adequate) and I suspect they will resolve with the emissions spec they are trying to hit in the next rev for California.

 

I don't know what CARB emission spec GM "wants" for the Volt, but PZEV requires a 10 year, 150k mile warranty on the traction battery. I will be VERY surprised if GM agrees to that requirement.

 

They've already stated the work is underway. (Granted, that doesn't means it's a reality.) I think competitively they don't have a choice.

 

Short trips is blended mode is definitely a bad thing when it comes to efficiency and pollution. I don't get nearly the mileage promised by the prius because of short trips. I'm fine on long trips, but I take many 2-5 mile trips. On these electricity is much better. My point on blended mode was for the very cold and you want a warm cabin. Here electric heat is very inefficient and the volt forces a blended mode, which is a better choice most of the time. It would be nice if they put a button in the car to lock it into ev. The upcoming volvo phev v60 gives the driver all the choices.

crap ice versus crap battery or after market kit. The volt does put it in this mode when its very cold out. No driver choice though, other than mountain mode to force it to save battery.

AFAIK the epa and carb do not have any evaporation tests that don't run the ice. There is a pressure test to see if there is leakage and all cars must pass this. The old tests need to be changed and hot soak time and temperature is being increased, I'm not sure if these figures are reported yet, but cars are run then soaked to see the emissions out of the canisters. Both EPA and CARB need to rewrite test procedures for hybrid and phev emissions testing, these don't take into account how these cars really are run. Its not as if these cars really sit and idle for long periods of time, why is this a major part of the emissions test.

+1

pzev is planned for 2012, flex fuel is planned by 2013. When they are doing the pzev modifications maybe they will do other enhancements such as bettery battery packs. We will see if the volt meets these goals next year.

 

A quirk in the CARB regs lets an EV have ZEV status while only warranting the traction battery for 80k miles, while a hybrid must warranty the pack to 150k miles for PZEV cert. This is a real blow to the Volt because it is kept out of HOV lanes throughout most of the US, and it loses out on some state subsidies too.

 

My comment was directed toward those individuals pushing the notion of Volt not having to start the gas engine.

If Volt can run with the gas tank empty, why even have it? I bet most of the owners will have only half the tank full.

As far as Evap emission goes, this is CARB data:

 

Yes, I agree. They claim via remote control that the vehicle can pre-heat/pre-cool when it is plugged in without running the engine. (I reviewed the online manual and it parallels this thought.) That being said, the nightmare scenario, as far as I can tell, for the current Volt is being garaged with no electricity in an extremely cold climate or being stuck outside in the same scenario. In that mode, ICE must run due to current draw.

I believe this is one of the reasons they're pushing them out West so much. If you remain in a fairly temperate range most of the year, this is less of an issue. Like I said, interesting design trade-offs for 1.0.

For me, I need a PHEV or an EV that has 120 mile range electric only. That's my magic number.

 

If you don't floor the pedal, Prius PHV's gas engine won't start. Is it bad to show when the gas engine would blend in (EV bar in real-time)?

 

It does need to start the ICE engine, only in:
- Extreme temperature conditions
- No charge on battery
- Pre-heat or pre-cool requiring excessive current draw when not plugged-in
- Old fuel

The reference to running empty is from the Owner's Manual. (You can download this online.) I'm using the manual and my test drives as the majority of my reference points.

I think this is a good idea -- it feeds back into one of my recommendations around instrumentation. The Volt's LCD screens provide a wealth of data to the driver. The HSD has similar information but it's buried. This is one area Toyota could clearly improve.

 

Owners found out that the gas engine also started even when it was plugged in! There were concern about carbon monoxide poisoning because they charge the Volt in the garage.

 

That's interesting as it defies the normal operating parameters they list in the manual.

 

Prius PHV shows exactly when the gas engine will run in real-time. I don't understand why people wants an EV button so the gas engine doesn't turn on when you floor it.

 

Yes, that is true. I just don't find the display particularly intuitive. My comment here was more focused on the design and UX of the software. There's some good learnings to glean from both Ford and Chevy's new panels.

 

cmon, you still shopping this crap about co poisoning. Open the garage door if you hit remote start. Its not that hard.

I was talking about the volt being able to lock it in ev in the cold, but why do you persist in this idiocy.

It has been reported that people can't just stop it from turning on, including by prius chat test drivers, motor trend, and car and driver. I know that I can not make it up the hill in the standard prius ev at any speed warmed up. Do you think I should be staring at the hsi and feathering the accelerator in normal city traffic? Look at the surveys and reviews if you think no one thinks they need an ev button. I think you were the only one in the survey that thought that the car should not give the driver control, and toyota knows best ;-)

 

That would be counter-productive, since the amount of cold air allowed in is quite significant... especially if it's windy.

And even if there were no poisonous fumes, you'd still have to deal with the lingering smell.
.

 

You are assuming the sensitivity of the gas engine blending with the Prius PHV is the same as the cordless Prius. Not even close! There is no HSI bar in PHV mode. It is replaced with the EV bar.

Opening the garage door would just make preconditioning less effective (cold air coming in). See MT's account below with the garage door closed. Lyle (ex owner of gm-volt) probably chose not to use this feature because it is useless, wastes electricity and add additional risk.

So far I’ve been underwhelmed by the preheat feature. Given 15 minutes in the garage while plugged in and set to 75 degrees the digital thermometer readings weren’t far above ambient.​

Read more: Long Term Chevrolet Volt: Fuel Economy Heats Up Quicker Than the Cabin – Motor Trend Blog

 

Have you smelled the volt after a remote start? I noticed no problem in remote starting my lex. The lex released much higher levels than my prius or the volt. Have you ever owned a car with a remote starter?

Why I assumed that it hard to modulate from the reviews and first hand reports. How fast can you accelerate from 20-50 in 30 degree weather? can you manage an on ramp or merge without staring? can you show the video? What about 100 degree weather with the airconditioner. Can you get to 60mph in 15 seconds? 20 seconds? Can you easily look at it in city traffic while driving? I have looked at a couple of videos and it does not look easy and acceleration is not fast so you need to watch for a long time.

Let me get this straight, you are saying that the volt will kill you, but now its just not as effective. Which is it. CO poisoning, or it takes a little more energy? These are quite different. The CO poisoning is just plain false.

 

I thought I posted before. Here we go again. You tell me if a cordless Prius can do that.

Maybe you misunderstood? Preconditioning feature takes about 12 minutes to increase 10 degrees cabin temp. If you let the cold air into the garage, it will take even longer to heat up the cabin.