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

So you want to invent yet another metric? I think this one is silly. And there is no measure that would be true "regardless of how you drive". I've seen PHV milage from < 40MPG to > 200MPG. How you drive will always matter.


In my volt the range to 100MPG would be about 100miles for me, on a good day, and 90 on most fair weather days and 75 in the winter. So its also not just driving, but all three T, temperature technique and terrain.



One could ask about your range to 100MPG metric doing standard driving, e.g. MPG composite

Using EPA estimates for a PHV it would be just under 22miles. 11 on Ev+a little gas, and 11 miles @50MPG.

Using EPA estimates for a Volt it would be 55miles, 35 on EV and 20.5@37mpg and


But still don't see the point of yet another metric.

And for the Leaf/Tesla's out there.. range to 100MPG.. is infinite unless you count their other car as well.

 

Simply not true. If all other elements are equal it would be true, but weight is only one dimension in a system and if one were to say reduce weight by reducing the engine size it could reduce overall efficiency. If one reduce weight but increased aero-drag, it could reduce efficiency, etc.. Unnecessary weight, i.e. weight that serves no purpose, should always be removed.

In the case of the Volt, the extra weight is a battery system that allows it to, overall, achieve better, way better, real-world MPG.

We don't have sufficient data to draw a conclusion on a comparison of MPGe, but I'll put mine up there as an example, I'm over 105MPGe since end of October. The best PiP's MPGe on the spread sheet is iRun26.2 at about 90MPGe... so it does not seem the weight of my Volt is hurting it much.


P.s. if you reply with quote it will automatically indent stuff to make it easier to distinguish your content from that you are quoting.

 

IMO, the Volt is only good for short runs. take in on the highway for 500+ mile trip, getting stuck in stop and go construction traffic and the Volt is nothing compared to a Prius, plug-in or otherwise. the Prius is MUCH better overall car in the real world.

on a recent trip to the Northeast, during one part of the trip.....100+ miles, we averaged 74.9 mpgs. and that was without really trying......

 

Did you read the material you quoted in the reply? Its not JUST licensing, its not clear that an HSD+atkinson would make a big difference.


Consider that the Lexus HS250h uses HSD and the HS 250h engine runs on the Atkinson cycle. It also includes an exhaust-heat recovery system to reduce engine warm-up periods (optimizing engine start-stop times).
The HS 250h can be operated in either driver-selectable EV, Eco, or Power modes. The EV mode is suited for short-distance pure electric driving at speeds of up to 20 miles per hour (32 km/h), the Eco mode can be selected for the greatest fuel efficiency in mixed gas-electric driving, and the Power mode offers more performance in contrast to the Eco mode. The 0-60 time is listed at 8.4 seconds, just a bit faster than the volt's 8.5 seconds.

So by your logic of using toyota technology with Atkinson and HSD, one might expect the HS250 to get much better gas milage than a volt.



The HS 250h's EPA fuel economy is estimated at 35 MPG city and 34 MPG on the highway, 34 Combined. The Volt is 35 City, 40 Highway, 37 combined.

Thus, as I said, it is unreasonable to just presume that just using Atkinson and HSD would help the Volt.

 

If you are doing more miles per year in 500+ mile trips, I would agree a Prius or PiP would be better. if you take 5000 miles of long trips a year, out of a total of say 15000 miles a year, the Volt will likely use much less gas with overall fuel cost much less per mile.

If you get 74.9MPG out of prius in 100+ mile trip, you'll likely get 45-50MPG out of volt in gas mode and in a 100+mile trip get 80MPG or better out of a volt, see http://priuschat.com/forums/chevrolet-volt/108629-volt-mileage-data-130-mile-trip.html.


Real world MPG average for Volt, from 7.5Million miles is 123.9 MPG.

Real world MPG average for Prius over 72,000 miles is PHV 70.5 MPG

Real world MPG average for 2010 Prius, over 5.3Million miles, is 47.4 MPG

And while the Volt and PiP use some electricity, you can buy green electricity and miles per dollar, electricity is generally way cheaper.

If you are the exception 1% that drive mostly in trips > 200 miles in length and get 72MPG from your 2010 prius, then yeah go prius. But for the rest of the more average people, real world data is very telling. Just not telling the same story you are.

 

I was simply using the same term you used in your own post which I quoted. If you find 100 mpg on a 26 mile commute compelling, surely the same commute with 1000mpg is even more compelling??

 

Consider this anecdote from a new Prius C driver, and kudos to him because he had been driving a Tundra crew cab at 15mpg:

 

The fact that people continue to ask for more information should make that obvious.

And since when is providing data to allow people to draw conclusions on their own not a good thing?

 

John,

I totally agree, let the data be presented to anybody who wants to look at it.

By all means, people should always be allowed to draw their own conclusion.

Yes, people are asking more questions and yes it is quite obvious, it is very, very clear.

DBCassidy

 

Did you read the material you quoted in the reply? Its not JUST licensing, its not clear that an HSD+atkinson would make a big difference.

Maybe GM didn't want to? F**D has licensed earlier versions of Toyotas' HSD to use in their vehicles.

DBCassidy

 

GM had numerous opportunities to get their hybrid design out in the market. GM said numerous times there is no market for this type of car. Toyota forged ahead, refining, perfecting the Prius HSD over numerous years.

DBCassidy

 

And yet, the Volt is a pretty decent car. If you have a problem in general with GM, that's fine, and skepticism about Volt reliability is fine too. It looked really grim when the fires were reported. But for the Volt, it is at this point a case of so far, so good.

Prius HSD is clearly the most efficient gas-electric powertrain in the world. However, Toyota are clearly at a pivot point. As you say, HSD has been perfected. So what will Toyota do next? And is it better to wait for Toyota to get it right, or buy a Volt or a PiP?

 

I've never heard anyone ask for that type of information.

Providing data that was not requested in a format that is misleading is not a good thing.

I dislike it because as measure it downplays how far one can go with NO gas, which the real goal. It suggests that 100MPG is good, which I now consider a bad day, so its misleading people into thinking they are going good when, in reality, they can do much better.

What do you what does it explain that people need to know?

 

Noone here can answer why GM did not. But I provided technical arguments why HSD and atkinson alone do not make a car more efficient than the Volt or the Lexus HS would be like the Prius, but its worse than the Volt. If one designs for higher performance, as both the Lexus and Volt did, one often gives up a bit on fuel efficiency. But with the Volt's EREV design that loss does not mater very much.

F**D needed to when it became clear they technology they independently developed in parallel (temporally) was so similar to Toytota's patents that it could have been a bloody battle so it was determined to be cheaper to cross-license stuff than fight, see this article



GM did not need to as they have their own really good tech. The Volt leap-frogged the basic HSD design. The two-mode hybrid that GM developed earlier allows vehichles that can tow and work as a work truck. Yeah two-mode is not as efficient as HSD, then again it does things simple HSD cannot. And a someone buying a Silverado Hybrid rather than a standard Silverado will save more gas than someone that trades a Prius for a PiP or even 35mpg Civic for a 50mpg Prius. So what GM did matters, even if its not prius eco-chic.

No doubt, GM missed the early boat.

But since they were working While toyota said for years that Plug-in would not work.. GM proved them wrong and now its Toyota's turn to have to catch up.

 

For an entire decade, we were told price was a major purchase priority for any new fuel-efficiency technology to be accepted by the masses. That's how the $3,000 to $5,000 plug-in premium come about for Toyota and the $30,000 target for GM with Volt.

Then came the fallout, when Lutz started campaigning for heavy government subsidies and the $40,000 base price was finally revealed... which is how I became so outspoken, asking "Who is the market for Volt?" Then came the range (40 mile, all conditions) and engine (50 MPG, combined rating) expectations not being met. So, physically checking out the car itself became pointless. After all, those endorsing the "early adopter" perspective said to just wait anyway.

But today with another long-time Prius owning friend, we stopped at the local Chevy dealer. A salesperson escorted us over to an open Volt to check it out, though somewhat irked knowing I had absolutely no intention of buying one... since I had come there in my PHV and openly said I was there just to measure the interior.

Wow! I had no idea Volt was that much smaller inside. I'm average height for a man (5'8"). So when my head touched the ceiling in back, it only took a moment to realize it would be difficult to remain objective. In the driver's seat, it was clearly shorter there too. I measured, though it was obvious just by sight. There is 2.25" less headroom. The cargo area is smaller too. The sunken floor would make loading large cargo a pain, not flush as with Prius. My 3-wheel recumbent bike simply wouldn't fit either. When I asked about carrying bikes on back, wanting to know if anyone had figured out how to use a strap-on rack even though Volt doesn't have a back bumper for it to rest on, I only got a hitch suggestion... which made me wonder how often that would scrape considering the lower ground clearance.

That salesperson and the other who came to answer questions when we stepped inside were polite & helpful, but clearly didn't like Prius at all.

We already knew legroom in back was less and there wasn't seating for a fifth person. But now finding out about headroom and confirmation about the cargo area, more than ever I have to wonder who the vehicle was intended for.

With PHV having a base price of $32,000 and offering a larger interior, I see it appealing to a much wider base of consumers.

 

I am not so sure. Volt requires more electricity per mile (360 Wh/mi) vs. Prius PHV (190 Wh/mi) because it is heavier (3,780 vs 3,150 lbs) and the gas engine does not blend and sit as a dead weight. Those are EPA numbers.

If you are talking about 10 miles at 30mph constant speed, that may be true. However, that's not realistic in the real-world traffic so we should use the EPA numbers derived from EPA test cycles.

Blending in the gas engine saves recharging time and increases efficiency by reducing dead weight in the plugin hybrid. Clearly, Volt was not designed for maximum efficiency or lowest emission. It was designed to maximize electricity usage, regardless of other factors/trade offs.

EPA uses 33.7 kWh per gallon of gas. That's how Volt's EV is rated at 94 MPGe. The "wasted" 8.8 kWh in every gallon at 37 MPG (vs. 50 MPG) is what dragged the Volt's overall composite (electric+gas) to 60 MPGe.

An oversized 35 EV miles battery pack comes with a set of compromises. Volt uses 4x more electricity than Prius PHV, per charge. And so does the recharge time, roughly. The impact of that depends on the individual driving pattern. It could be

I was not fixated on the recharge time. I only bring it up whenever a Volt owner mention gasoline consumption with the electric miles included. My response always have been how many kWh did you use and how long did it take for you to charge it?

 

Multiple recharges would just boost the MPG and the base is the class leading 50 MPG on regular gas. That pretty much eliminates separation anxiety from the plug.

If one's driving pattern can do multiple recharges per day, the plugin with an oversized battery is at disadvantage from the weight, cost and efficiency point of view.

Volt may recharge at slightly faster rate but it consumes a lot faster than Prius PHV. A full recharge is 10 hours vs. 3 hours.

 

42% statistic is from the utility factor of SAE J2841 standard, revised in 9/2011. It predicts that 35 miles EV range would cover 58%. The data is from 2001 U.S. DOT National Household Travel Survey.

 

It doesn't matter. It runs on electricity for the first 35 miles (!) without the gas engine starting (bad, bad).

The amount of electricity consumed, emission created by generating it, or the time it takes to recharge doesn't matter because that happens while I sleep. What counts is the amount (or the lack) of gasoline I consume.

/sarcasm

 

If you want to talk EPA wh/mile for the PHV, please provide a citation. As far as I know there is no EPA estimate of PHV Wh/mile because it cannot complete EPA tests with just electricity. The sticker was 29kw/100miles + .2 gallons.
And you cannot compare a kw+gas to tests with the Volt on a full EPA cycle. Its probably a bit more efficient, but not a lot. My Volt wh/mile is about 260, PC spreadsheet is at 225.