It’s also more efficient to just put that power straight to the road. Charging the batteries only makes sense if you’re plugging it in and getting your electricity from the grid, where it’s cheaper than burning gasoline to make it.
I suppose it also makes sense if you’re at the last gas station for hundreds of miles and want to extend your range by charging the battery then tanking up, but I don’t think they really planned for that. (And you’d still be no worse off than with a regular non-hybrid car in that situation).
" SonofSpermcube" makes a good point…
For those of you who have tractors and the like with hydrostatic and have driven gear as well in these tractors, it’s easier to understand why the series Volt with a constant running diesel is NOT as efficient as a gas in parallel hybrid. The diesel does produce maximum power but it’s fuel efficiency starts to drop dramatically as the RPM increases over idle to that power band; great for construction work with hydraulic motors that absorb the load shock of direction change and implement work, but still no where near as efficient as a direct drive gear that can vary rpm with load. That’s why gear drive in tractors is preferred for large scale farm work in the fields, and construction uses hydro.
Over the road travel is much more efficient with a diesel/conventional transmission than running at higher RPM to charge a battery. It’s the nature of the beast.
What will make the Volt practical is a strong enough electric motor/battery and a minimum use of around 40 miles per day to plug in at night—not running off a charging diesel. Locomotives use the hybrid to eliminate the transmission which would weigh more than any motor to take the stresses, and becomes efficient for massive loads with the torque requirements of the electric motor.
That’s why the diesel may be great at home power generation but not for over the road, varying power demand from electric generation use. A hydro/diesel uses 50% more fuel per hour running at peak power efficiency than the gear driven at varying speeds; but while it’s running at peak efficiency shuttling for construction for example is safer, easier on the engine and more work per hour, but not greater distance traveled per gallon. Again, if you operate diesel equipment in it’s various forms you’d understand better than I can explain…sorry. Better computer control over this disadvantage will make the diesel a bigger player, but why bother if all electrics may be closer at hand.
The interview I read with the GM contact indicated the Volt does not recharge the batteries, except to keep them from falling below acceptable minimum levels, and that once the 40 miles are up the engine only powers the electric motors. It would seem that recharging by the motor when max power not needed would improve performance, like when current hybrids have both battery and engine power available. For the Volt it’s either/or.
I think we agree on the way their power system works. There is regenerative braking, but it does not seem to provide a lot of charging, either. As SoSC said just above, it is more efficient to dirrectly power the generator with the gas engine. If the IC motor were larger, it could provide enough power to regenerate the batteries and power the car, but then it would not be as fuel efficient. I’m sure they thought long and hard about how to impliment the Volt. Their future depends on it, and I can’t imagne that GM would take it lightly. We can disagree about their design, but they have to live with it.
In my very humble opinion, GM “has” thought long and hard about how to delay a worthwhile EV, make it as expensive as possible and keep a balancing act between promoting it’s gasoline powered vehicles and the bogus expectations of the Volt (200+mpg) in concert with the fluctuating oil prices and public demand. Look at their ads and how they follow the oil prices, fluctuating between the Volt and their SUVs.
ICE makes money EVs do not and the Volt has been used as an advertising ploy for several years now. The same time the Volt comes out, Toyota will magically start importing it’s plug in hybrid Prius with always slightly more miles between charge. It’s a song and dance between auto companies to maximize profits from both sales and govt. bailouts and the ICE is still the best vehicle to accomplish it.
GM will commit themselves to EVs only when they start selling washing machines and electronics and compete with Sears at the malls and get totally into banking as they have been trying to do with GMAC loans for home mortgages. They will slowly loose their image as a car company.