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The car sounds great. But, A quick question. I read 600 miles on a tank of gas. Believe it was 6-7 gallons. If it only goes forty miles on Batteries then it is going 500+ on gas. Why not leave the batteries out for now and just make the thing without them? I'd buy it and it would have to be a hell of a lot cheaper. I mean 30K with batteries or 20K without is a no brainer. I'm sure theirs a reason that GM doesn't do it. Money being the real reason.
 

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Optimization

Without the batteries, the ICE could not get max mpg. The batteries allow the ICE to run under optimum conditions. The ICE is inefficient when providing power at startup or high rpm. The ICE is sized (71 hp) such that it cannot supply peak power (209 hp) to the motor, only the average of extreme conditions and worst case power at the max cruise velocity, 110 mph.
 

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Discussion Starter #3
O.K. No batteries in the car means plenty of room for a larger motor. Up the motor size by 50% I'll take 80 miles a gallon. I still don't get it.
 

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Why do auto manufacturers make hybrids?

Car manufacturers add an electric motor and batteries to cars becaue ICEs are inefficient under certain conditions. Look at an ICEs torque curve. Low torque at low speeds. An electric motor provides max torque at low speed. The electric motor and batteries optimize operation providing the higher mpg.
 

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Micheal, think about it like this; Under normal cruising, driving any automobile does not require much power. IIRC, the typical car on the highway only requires ~40hp. So why do we not just put 50hp engines in every car? The answer is that to accelerate it requires much more energy than it does to cruise. A normal automobile must have an engine sized to meet every energy requirement, even though it rarely needs it. An ICE is, in a sense, a 'jack of all trades, master of none'. Using a small ICE to drive a generator, offers two benefits. First, it allows you to operate it at the level in which it produces its highest efficiency (BSFE?). Secondly it allows you to use a much smaller engine. The engine does not have to be sized to meet pathological conditions. It can be sized to a level that under normal circumstances it would produce a small surplus of energy that can be stored in batteries. Typically the small ICE would be able to offer just enough power to cruise while generating a small surplus that will be stored in the batteries. Under conditions in which you need more power than is currently generated, the propulsion system will be able to draw upon the energy stored in the batteries.
 

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The car sounds great. But, A quick question. I read 600 miles on a tank of gas. Believe it was 6-7 gallons. If it only goes forty miles on Batteries then it is going 500+ on gas. Why not leave the batteries out for now and just make the thing without them? I'd buy it and it would have to be a hell of a lot cheaper. I mean 30K with batteries or 20K without is a no brainer. I'm sure theirs a reason that GM doesn't do it. Money being the real reason.
I believe the 500 mile range was for a 12 or 13 gallon tank, which has apparently been reduced to 6 or 7 gallons. I also belive that the Volt is suppossed to get 50mpg when running on the ICE (with LI-ion batteries). So without batteries the car will get substatially less mileage (for the above reasons), similar to a typical gas powered car.
 

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Your misconception is that it doesn't technically run on gas. The gas engine only powers a generator which continually maintains the charge in the battery and gets 50 mpg for 400 or 600 miles depending on how large the fuel tank is. That is why the Volt is so different from the other hybrids on the market which use an ICE to power the car. So if you only used the car 40 miles a day you would use no gas at all. But if you run over 40 miles and run down the batteries you will not stop and need a tow. Pretty neat, if they can get it too work.
 
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