GM-VOLT : Chevy Volt Electric Car Site

An unknown area about the Chevy Volt is how much gas the tank will hold and how the possibility for stale gas will be dealt with. It is known the first 40 miles of driving will be from the electricity of a fully charged battery. After that the car will get 50 MPG.

I was recently told by Volt vehicle line executive Frank Weber that “the gas tank will be between 6 and 10 gallons.”

Below is some further detail I was given by Volt lead engineer, Andrew Farah:

A long standing secret seems to be how large the Volt’s gas tank will be, can you clarify?
Its not a secret. I’m still balancing (the decision). I can trade off fuel tank size for other things. As we’re taking the vehicle through this critical phase of development this calendar year, there’s a strong likelihood I’ll still be making changes to that variable. And rather than throw a number out, we have said the car is going to go several hundred miles. Exactly how much is something we’re going to be tuning and trading off for other things.

So the size of the gas tank affects the mass and thus may be varied according to your needs?
Certainly. Fuel is very heavy and it also takes up space so maybe we’re going to use some of that space for something else too.

Have you solved the stale gas problem?
I’m not so worried about that. Most people are going to use up some fuel at some rate, probably faster than six months. Fuel is certainly going to be good for six months without concern. Most people are going to take one or two long trips in six months. We’re not designing this vehicle as a pure EV for a reason. Most people realistically while they’re going to get their 40 miles and there’s going to be five days a week when they may never use any gas at all, there’s a strong likelihood that they are going to use enough gas that this isn’t going to be a significant problem for most people.

So you feel you don’t need to build in a system to deal with it?
I don’t think we need to build in a special system.

If somebody never uses their gas in a year and a half will the car remind them about it?
That’s one solution, but if you go read the regulations about fuel management and evaporative emissions, (you will see) we have to limit our evaporative emissions to almost nothing. If you limit your evaporative emissions to almost nothing, things don’t get stale very much.

Take any volatile fluid, in the sense that it has a low vapor pressure and keep a lid on it and what happens? Almost nothing. Its not the same as in a lawn mower where you don’t have a sealed system. We have a sealed system. So there is something we are doing, it is not particularly special, but thats what we’re going to do.

Obviously the Volt can be driven without gas, in fact that the whole purpose. The range extender exists only for if you have to go further than 40 miles between charges.

One thing to consider is what would happen if the car ran out of gas after the battery has reached its depletion point, or was in charge-sustaining mode. Since there would still be charge in the battery, it is conceivable that the car could be engineered to dip into that a little and give the driver a “limp-home mode” that might allow 1 to 2 miles of slow driving to get you to the gas station.

The New York Times has just reported that Volt executive Frank Weber mentioned such a limp home mode might be available on the Volt.

Or will it?

I just recently had asked this same question to Mr. Weber’s colleague, Bob Kruse, who is GMs director of Hybrids and EVs.  My questions and his comments follow:

Will there be a limp home mode, if you run out of gas at the same time you’re at battery depletion, allowing the driver a couple of miles of low speed driving?
If it’s your Volt, are you willing to wound your battery for that convenience?

If it happens very rarely it may not impact the cells longevity.
Well I’m the expert on that and is that something that you’re willing to sacrifice, the longevity of your battery in order to overcharge it?

Ideally no, but I think if it were a dire situation the car could give you a big red button on the screen…
I could let you do it but you can’t expect me to give you a life of the car battery of you want to operate outside the norms. But we do have Onstar so if you use it they’ll bring you a gallon of gas.  I don’t know whether were going to do it (have this feature) or not.

So it looks like this idea is probably still up in the air.

Would you want this feature?

Natural gas has rising potential for use as an alternative fuel for vehicles. Indeed natural gas vehicles already exist using compressed gas (CNG) as a fuel.

Reserves of natural gas are considerable, cost is low, and domestic supplies are twice as large as that of petroleum. This had led many here to speculate that natural gas would make a great range extender option for the Volt, or as a primary fuel source for other vehicles. As well, oil tycoon T Boone Pickens has been promoting a plan to move the US to CNG vehicles.

GM Europe President Carl-Peter Forster said that he wanted European governments to encourage the use of CNG, stating “we need a policy that creates concrete action now to make…CNG widely available.”

GM already has the capability of making natural gas vehicles, but unlike Honda, has no models available in the US. I asked GM spokesperson Dee Aleen about GM’s US CNG car production plans. Dee stated, “In Europe we have the CNG Opel Zafira and Astra, and Chevrolet LPG, and I believe some models in Asia — but nothing in the U.S. ”

I also asked whether CNG would make for a good range extender in the Volt. He replied, “Let us get the original version out before we start having variants. As we’ve said from the beginning, even when no one believed we were even serious, the range extender can be gasoline, E85, diesel, hydrogen, cooking oil, solar, whatever . . . as long as it can efficiently regenerate the electricity in the battery.”

Investment firm Lehman brothers has indicated that they believe oil prices have peaked for the next few years, citing signs that tight supply and demand conditions are loosening.

Oil peaked at over $147 barrel on July 11, and now has retreated back to $115.  Hopefully to continue to drop.

High prices have led to reduced global and US demand, and the end of China’s hoarding in preparation for the Olympics has occurred.

Further, speculative forces also appear to be declining.

Source (Reuters )

Larry Burns is GM’s VP of Research & Development.  He has just written a post on GM’s corporate blog entitled Natural Gas: An Enticing Alternative .

He reiterated GMs position that there is no single solution to achieve petroleum displacement, and that a multifaceted approach is needed.

Natural gas is described as a good transportation fuel alternative because it is "abundant, affordable, and relatively clean."

He states that GM can in the mid-term "leverage natural gas to create electricity for the Volt and future variants".

For the near term he indicates natural gas could be used in combustion engines and hints at what may be imminent production plans; "we are exploring a dual-fuel approach with natural gas and gasoline for U.S. customers."

As well Burns states that GM believes the government will have to play a role to encourage adoption of and infrastructure development for natural gas through incentives.

Source (FastLane Blog )

GM has a marketing motto, "gas friendly to gas free", and although we here clearly are focused on the Volt, GM has been moving towards energy diversification, including promoting the use of E85.

On Sunday, Minnesota governor Tim Pawlenty announced that the National Governors Association and GM will work together to expand the nationwide ethanol (E85) infrastructure and distribution network.

GM has been steadily expanding the percent of their new vehicles that are flex-fuel capable, and for 2009 will have 18 flex-fuel models. Indeed the Volt’s generator, when it arrives, will also be E85 capable.

GM has recently formed strategic partnerships with the companies Coskata and Mascoma both of which aim to efficiently mass-produce ethanol from non-grain sources.

As per GM VP of Energy Beth Lowery, “GM continues to believe ethanol is the most significant near-term energy alternative to offset the increasing demand for oil. To make ethanol a viable alternative to gasoline requires sustainable production methods, a variety of vehicle offerings and a robust infrastructure to make the fuel available to consumers.”

It is noted that at present there are less than 1700 E85 pumps at the nation’s 170,000 gas stations.

Source (GM )