Comments on: Under What Conditions is the Chevy Volt’s Quoted 40 Mile Electric Range Modelled?

By: БAKИHEЦ

БAKИHEЦ — Thu, 20 Aug 2009 08:08:51 +0000

Я бы кое-что добавил, но по сути сказано все.

By: ricardoRI

ricardoRI — Mon, 27 Apr 2009 16:50:25 +0000

My 1970s diesel VW Rabbit often got 50+ mpg, and always over 40 mpg even with the air conditioning on. Why all the fuss about Volt and 40mpg?

By: stas peterson

stas peterson — Mon, 23 Mar 2009 18:23:37 +0000

There are significant difference from a Prius and its highway mileages. The engine is a 1.4 liter versus a 1.8 liter, 22% smaller. It is at a relatively constant rpm. I expect that the engine is tuned tuned for maximum efficiency at that rpm. That alone could be responsible for a 20% further improvement in mileage.

Y’all don’t have a clue as to what the fuel economy of an optimized 1.4 constant rpm engine is at that rpm. Buit I remember all those Mobil economy runs where all the tricks to increase mileage were employed by the drivers to produce impossible mileage figures.

NONE of them could duplicate the efficiency provided autiomatically ,by a constant RPM operation at an optimized point in the operating band. HCCI will show up there too first I would wager in Gen II or III. Add another 20-30% efficiency too.

By: Ed M

Ed M — Wed, 31 Dec 2008 01:11:43 +0000

GM: The 40 mile range is modeled on the EPA city cycle (federal test procedure) – and the 40 miles is GMs target for battery END OF LIFE. The EPA city cycle includes a range of starts, stops and accelerations but with no A/C.
Since 40 miles is end of battery life, we could assume that when the battery is new it will be greater than 40 miles. In future there should be upgrades to the battery that will deliver 40 miles with the A/C on. The first generation batteries are likely to be primitive compared to future generations.

By: wow

wow — Thu, 25 Oct 2007 03:57:20 +0000

Rashiid,
Don’t be surprised if the cheapest high gas mileage car is more economical than the newest high-tech hybrid at first. The cost of electric drive will come down as mass-production ramps up and competition sets in from multiple suppliers. Don’t forget that you spend $k’s on gas per year if you’re driving 15,000miles/year. And gas prices are just going to go up.

By: Van

Van — Wed, 24 Oct 2007 12:21:21 +0000

Hi Steven B, yes, my expection of actual Volt performance is based on numbers from GM. Recall the article where the power necessary to sustain freeway speed was given? I used that to calculate a 24 MPK freeway performance.

By: Mike756

Mike756 — Tue, 23 Oct 2007 12:50:33 +0000

Steven B #40

What are we supposed to do, just say ooh and aah? You don’t think it is a fair question to ask what the highway mileage will be? I think everyone knows that we don’t have the actual specs, but they have released some numbers, i.e. the 40 mile range. However, it makes no sense to say “40 mile range” without qualifiying how that range was determined. They are going to have to release the highway mileage at some point anyway, and as a fair percentage of commutes will be at highway speeds, I think this is a fair question to ask.

By: Rashiid Amul

Rashiid Amul — Tue, 23 Oct 2007 12:19:32 +0000

Mike756, I won’t give up yet. I am waiting for the real numbers and realize that some of this is speculative.

Lyle, have you heard anything about the Volt tour schedule? I haven’t had much luck on the Net. Connecticut is having an International Auto Show next month and was hoping the Volt would be there. Any ideas? Thanks.

By: Steven B

Steven B — Tue, 23 Oct 2007 10:57:31 +0000

Sorry to point this out, but do any of you have the actual specs for the Volt?!? I don’t think you do. You seem to be playing with calculators here and all without the appropriate variables for your calculations. GM said the Volt will be designed for 40 miles. Then you end up saying that it will be for 30 to 24. They are the ones developing the car and they have not released all the specs. I suggest that you wait until whoever there reads our posts gets us an actual answer and stop with conjecture. It’s interesting to find out that range is based on city cycle. It’s also important to realize that highway driving will have a significantly different number. But in the end, all driving is mixed city and highway. And if you’re driving at 70 miles per hour, you had to accelerate to get there, and when you get to your destination, you will use your regen braking when coming to a stop. Let’s just wait for GM to find out and let us know what highway AER will be and stop guessing.

By: Van

Van — Tue, 23 Oct 2007 04:49:42 +0000

First, any mileage figure MPK, must be replenishment KWH, the number of KWHs you are charged for. To discuss internal numbers is misleading. So the RAV4 got about 2.5 MPK. The Volt should do better, perhaps 3 or 3.5 miles per KWH.

Also the end of life comment is vaporware, the car uses 8KWH of power at end of life, the reduction in overall capacity comes out of the unused 100-80 and 30-0 range.

So to back up, the 40 mile range is like the Prius getting 60 MPG city. It actually got about 45. So if we ratio it, the actual city mileage achieved may be as high as 30 miles per 8 KWH and the highway about 24 miles per KWH. That is absolutely outstanding.

As far as 1/2 the people driving over 40 miles in their daily commutes, you need to keep in mind that as the population ages and retires, many of us simply run to the store, the park, and the coffee shops. This is the dawning of the age of freeway golf carts!