Volt Birth Watch 174: Enough With The Prius Comparisons!
As we saw in the last VBW, the Volt’s range-extender still needs some software work. But efforts to to keep the gas engine from acting like a thrashing, disembodied dervish will have to balance the desire for smooth operation and maximum efficiency. And it’s looking like efficiency in charge sustaining (CS) mode won’t match the hybrid standard-setters. Volt chief powertrain engineer Alex Cattelan breaks the news gently to the true believers at GM-volt.com
You’ve got to understand that all of the decisions that we’ve made around this product are made because its an EV. That is the first and foremost thing that it needs to be. So because it is an EV some of the decisions that we’ve made around engine operation will be different than what Toyota makes in its parallel hybrid. For them they are always operating in hybrid mode so they need to optimize everything for engine operation.
In our case we’re optimizing everything for EV operation and the secondary is certainly going to be better than conventional vehicles, but were not necessarily totally optimizing the system for charge sustaining mode because we don’t want to compromise electric vehicle mode.
Cattelan goes on to describe the sophistication of the Volt’s constantly-updating efficiency software, sourced from the abortive Two-Mode hybrid system. And as the chart above shows, the plan for charge-sustaining mode is an interesting one. Essentially, it involves keeping the battery state of charge between 30 and 35 percent, once the 40 miles of (estimated) EV range is tapped. Which is a fine idea as long as the engine on-off improves. Otherwise, drivers might just find themselves nervously counting down the five percent charge range before the 1.4 liter range extender thrashes to life again. Hoping for an answer to that question, Gm-volt notes “I’ve driven the 2-mode and notice you can see the switched in mode of operation without feeling it in the car.” Cattelan’s response reveals the trade-off that’s in play:
Which is the goal, you don’t want you to feel it in the car, we don’t want the customer to know these transitions are taking place, but we need to be able to enable them for efficiency.
Later, when Cattelan has explained the efficiency benefits of having a range-extending engine that’s independent of the drive axle, Gm-volt pushes again on the charge sustaining-mode efficiency question, saying “It seems to me then you should make CS mode even more efficient then in a car where the engine always has to turn the axle?” Cattelan’s answer once again downplays the notion, saying
Right and it is more efficient than a conventional vehicle because they do have to have that engine coupled. Again were optimizing some of those efficiency point puts we are really doing is focusing on the optimization of the EV. There are trade offs because we absolutely consider this product an EV by nature.
It’s not a hybrid! We’re focusing on EV mode! More efficient than a “conventional vehicle” in CS mode! Which means, what, 35 MPG? As Paul Niedermeyer explained some 18 months ago, the Volt is going to have a hell of a time beating the Prius on a mass-market basis. Which is what happens when you come up with the marketing line (“40 miles without burning a drop of gasoline”) before you develop the car.
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- Tassos A terrible bargain, as are all of Tim's finds, unless they can be had at 1/2 or 1/5th the asking price.For this fugly pig, I would not buy it at any price. My time is too valuable to flip ugly Mitsus.FOr those who know these models, is that silly spoiler in the trunk really functional? And is its size the best for optimizing performance? Really? Why do we never see a GTI or other "hot hatches' and poor man's M3s similarly fitted? Is the EVO trying to pose as a short and fat 70s ROadrunner?Beep beep!
- Carson D Even Tesla can't make money on EVs anymore. There are far too many being produced, and nowhere near enough people who will settle for one voluntarily. Command economies produce these results. Anyone who thinks that they're smarter than a free market at allocating resources has already revealed that they are not.
- MaintenanceCosts I wish more vehicles in our market would be at or under 70" wide. Narrowness makes everything easier in the city.
- El scotto They should be supping with a very, very long spoon.
- El scotto [list=1][*]Please make an EV that's not butt-ugly. Not Jaguar gorgeous but Buick handsome will do.[/*][*] For all the golf cart dudes: A Tesla S in Plaid mode will be the fastest ride you'll ever take.[/*][*]We have actual EV owners posting on here. Just calmly stated facts and real world experience. This always seems to bring out those who would argue math.[/*][/list=1]For some people an EV will never do, too far out in the country, taking trips where an EV will need recharged, etc. If you own a home and can charge overnight an EV makes perfect sense. You're refueling while you're sleeping.My condo association is allowing owners to install chargers. You have to pay all of the owners of the parking spaces the new electric service will cross. Suggested fee is 100$ and the one getting a charger pays all the legal and filing fees. I held out for a bottle of 30 year old single malt.Perhaps high end apartments will feature reserved parking spaces with chargers in the future. Until then non home owners are relying on public charge and one of my neighbors is in IT and he charges at work. It's call a perk.I don't see company owned delivery vehicles that are EV's. The USPS and the smiley boxes should be the 1st to do this. Nor are any of our mega car dealerships doing this and but of course advertising this fact.I think a great many of the EV haters haven't came to the self-actualization that no one really cares what you drive. I can respect and appreciate what you drive but if I was pushed to answer, no I really don't care what you drive. Before everyone goes into umbrage over my last sentence, I still like cars. Especially yours.I have heated tiles in my bathroom and my kitchen. The two places you're most likely to be barefoot. An EV may fall into to the one less thing to mess with for many people.Macallan for those who were wondering.
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I think Pfizer is working on a pill for Range Anxiety.