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Eight 2011 Chevy Volts took the 1200-mile roadtrip.  (Source: Jeffrey Sauger for General Motors)
The Volt is withstanding the rigors of road testing admirably

The first preproduction models of the 2011 Chevy Volt hybrid electric plug-in vehicle were built earlier this year.  Since then, the vehicle has been put through a number of rigorous tests.  Starting yesterday, a fleet of eight Volts launched on the most ambitious test of the vehicle to date: a 1,200 mile road trip.

Chevrolet Volt chief engineer Andrew Farah is among those making the round trip from the Milford Proving Ground through Ohio, Pennsylvania, Maryland, West Virginia, before returning home.  The drive will take a few days and will require approximately 4 tanks of gas.

The drive is dubbed the "65-Percent Drive" according to Autoblog, which in GM-speak means the test drive made when 65 percent of the vehicle's hardware and software is done.  Reportedly, GM is actually about 90 percent done, but is just sticking to its traditional naming.  GM will complete 70, 80, 90 and 100 percent drives in coming months.

One thing GM is still tweaking is how much power from the gas-engine generator to put directly to the electric drive motor, versus using the generator power to charge the batteries.  GM is finding that frequently putting the power directly to the motor improves performance.  However, the generator will still charge the batteries in some cases, as well.

The engine will be run between 1,200 and 4,000 rpm, using factors like speed and power load requirements to decide on the necessary speed.  GM wants to keep the engine between 30 to 100 percent load, as higher loads reduce pumping losses.  GM was tight lipped about fuel economy under the old method (sustained charge) or the new method (variable speed, some power going directly to the electric motor). 

The company did say that the prototypes are getting good mileage -- over 300 miles on a tank of gas -- when operating in generator mode.  This is in addition to the vehicle's 40 mile all-electric range.  Another interesting test will be when GM runs the car's gas engine on E85 ethanol fuel.  The vehicles are FlexFuel designs, so they can enjoy both gas and ethanol.

As to the battery mode, the batteries are performing well and aren't getting too cold or too hot, both conditions which can degrade performance.  The cars aren't yet reaching the 40 mile target on a charge, but GM expects to pass that milestone on the next test, with tweaking.  On the trip, GM is testing vehicles both running on a depleted battery charge, and a full charge.

GM is also looking to fine tune and minimize noise, vibration, and harshness (NVH).  Currently, the gas engine typically won't turn on until the car is moving, at which point the noise will be drowned out by the wind and road noises.  GM, nonetheless, is pleased with the performance, and plans to further reduce NVH by tweaking vehicle parameters that effect the road and wind noise.

Other GM engineers were off testing Volts at Pikes Peak in Colorado.  One key concern is whether the Volt will reach a "tipping point", where the gas engine can't sustain battery charging, and the battery becomes depleted below the typical minimum of 30 percent charge.  Even a strenuous 14-mile trip to the 14,000-foot summit was unable to overwhelm the 100 hp generator, though, so it appears that the "tipping point" will never be reached in real world situations  -- if GM's claims hold true.

A critical test to come will be how the vehicle performs in cold weather.  In cold weather, the Volt starts with the generator running, to help heat up vehicle and jump-start performance.  Battery performance typically suffers incrementally worse degradation, the colder it gets (this is a major argument for ultracapacitors which perform favorably, but are more expensive).



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RE: looks
By mcnabney on 10/17/2009 1:51:41 PM , Rating: 2
They are all managed by Federal bankruptcy courts, but financing is typically arranged from large banking/investment institutions. For example, Enron and MCI/Worldcom didn't cost the Feds anything. I even believe that the court costs were paid from the remaining assets. The Chrysler bankruptcy involved Fiat and some cash there, but for the most part the court just assisted in negotiating new terms for some debts and discharging others. Before that can be done the entire financial structure of the business has to be studied to make sure there aren't tangential assests that can be liquidated. For example, in the GM bankruptcy the Saab and Hummer brands were sold. Saturn would have been, but Penske flaked-out. In GM's case the Feds played the role of a large bank by buying a major percentage of the business ownership after the previous shares were cancelled. This actually worked out as it should. The equity investors were punished first by getting nothing. Second, the bond holders only received a fraction of their matured value (that is where a lot of US funds went to). Third, management was fired w/o parachutes. Fourth, employee stakes were converted to shares which made them dependant on future prospects to have any value. If the whole thing fails, the Feds won't be able to sell their equity stake in the future to get there money back. Long story short - if you want the US taxpayers to get their investment back, buy GM products.


RE: looks
By Reclaimer77 on 10/17/2009 2:42:55 PM , Rating: 2
Ok I see we have fundamental differences of opinion that aren't going to be resolved by picking at the edges of arguments.

I'm apposed to the concept that any business is "too large to fail" and that it's up to the taxpayers, in a big recession I might add, to pick up the tab and bail them out. Especially without even a vote ! Taxation without representation ring a bell to you ? We weren't even given a CHANCE to have an honest and democratic debate on this issue. This is NOT the way things should be done. I, and a great many other Americans, are honestly sick and tired of crap being rammed down our throats before anyone even knows what's going on or has a say in it. The TARP, the Auto Bailouts, the "Stimulus", Tax and Trade, and now Universal Healthcare.

Period. No iff's, and's or buts. And I find your assertion that it's our patriotic duty to buy into the farce that is Government Motors, frankly, offensive.


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