230 mpg in the Volt? Chevy fudging the numbers?

[chuckm]

They're planning to use a 1.4L (turbo?) gasoline inline-4 engine as the generator last I heard. That was the death of it for me. Even in a super-lean-green-atkinson-cycle burning machine fashion I can't imagine it getting much better than 100 mpg out of it on gasoline alone. If they'd used something like a 600cc turbo engine, then I may have been more receptive.

I think it makes a lot of sense. Again, as Christ and cfg83 mention, as a series hybrid, the engine can be tuned to be a very efficient generator, running in a narrow rpm range. Size the engine/generator system to produce a bit more than 100% of 75mph, five passenger, plus 200lbs cargo, electrical load and there you go. That's a high enough load as to not strand anyone. Cycle the engine on and off as needed to maintain charge.

Joey,
It isn't a 190mpg engine. It is the advantage of a series hybrid, which smooths out the peaks and valleys of engine load. The engine switches on, runs at a specifically engineered load and rpm, and turns off. Conventional engine vehicles, including the Prius, allow the engine to vary across a broad range of rpm and load. The trade off for lots of flexibility is inefficiency. The other upside of a series hybrid is that you can eliminate mechanical losses, like transmissions and such.

[tjts1]

230mpg? LOL
If you believe this BS, I have a bridge in Brooklyn to sell you.

[NiHaoMike]

Originally Posted by superchow

Ah - 230 mpg in city driving WITH charging at home every night. Yeah, that's kind of like saying, "I get 100 mpg in my Civic. On downhills..."

Get me an original Insight, a bicycle, a rope, and a fat chick and I'll make you a car that can get infinite MPG on level ground. Only catch is that you would have to go really, really slow to make that MPG... But at least you won't have to recharge or refuel it.

[chuckm]

All I know is that when I'm running my non-Atkinson cycle Corolla engine at a steady 40mph, I'm getting between 65 and 75mpgs. If you use the current EPA driving cycle to measure a car that uses batteries only for 40 miles of driving, improve the efficiency of the engine my using an Atkinson cycle engine designed for a narrow rpm band, then 230mpg, using the current EPA test cycle, looks quite achievable, assuming a charged battery.

The real question is: What is the MPGe? When you count the power from the outlet, how does the number look?

How much is your bridge?

[jamesqf]

Originally Posted by joey

Indeed. Maybe they can come out with a sub-$40,000 model that just uses that 190mpg engine. Well, I guess they'd have to make the engine, you know, exist first. But after that...

Shouldn't be impossible, if you're willing to accept 0-60 in 10 minutes, and slowing to a crawl on even a slight upgrade. As we all should know by now, it doesn't take all that much power to move a car at constant speed on level ground, so if you optimize your engine to put out exactly that much power at its most efficient operating point...

[Daox]

Originally Posted by chuckm

The real question is: What is the MPGe? When you count the power from the outlet, how does the number look.

Quite true chuck. They aren't including the electric power from the grid in their testing at all at this point.

[NeilBlanchard]

Hi,

Apparently the "real" numbers on the Volt are 40 miles on a full charge, and ~50mpg while in the charging.

ApteraForum.com - Aptera Car Forum - View Single Post - GM claims 230MPG for the Volt, is a 300MPG rating for the Aptera too conservative?

The 230mpg number comes from driving 51.1 miles and not counting the 40 miles of electricity that you used.

[Christ]

Originally Posted by Daox

Quite true chuck. They aren't including the electric power from the grid in their testing at all at this point.

That's because it comes from Zero Point space in their testing. They've figured out how to make electricity from the energy of the universe, so they don't have to count "grid miles" since there are none.

Greedy baztids aren't sharing the seekritz, though.

[chuckm]

Wow. If that 50mpg during charge is correct, I'll be truly disappointed in GM. It would mean that they haven't built a matched engine/genset, and instead grabbed an existing wide-rpm Atkinson cycle engine. If so, GM sucks. If I can get a steady 50mpg holding 55mph on my non-Atkinson, non-lean burn engine, GM has not done anything revolutionary.

[Christ]

Originally Posted by chuckm

Wow. If that 50mpg during charge is correct, I'll be truly disappointed in GM. It would mean that they haven't built a matched engine/genset, and instead grabbed an existing wide-rpm Atkinson cycle engine. If so, GM sucks. If I can get a steady 50mpg holding 55mph on my non-Atkinson, non-lean burn engine, GM has not done anything revolutionary.

Ok, you try getting 50+ with your engine while you're charging a *whatever* amp hour battery pack at full load...

Why not compare apples to apples?