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News Flash! Gm Breaks Laws of Thermodynamics

For every auto manufacture there exists a direct correlation between engine size and vehicle weight. A hybrid can bend these rules slightly because the electric motor is more efficient to supply power at low speeds, stopping and starting without wasteful idling, regenerative breaking advantage etc. The standard Civic at 2633 lbs is powered by a 1.7 liter engine. The Civic hybrid at 2877 lbs is powered by a 1.3liter engine.

The Chevy volt is claimed by GM to be a fresh new technology to put GM ahead of all competitors. Unlike a hybrid which is driven directly by both a gas engine and an electric motor, the Volt is only directly powered by its electric motor.

The Volt is comparatively an extremely heavy all electric car of 3520 lbs with the addition of a 1.4 liter engine used only to charge the batteries. It makes sense that fully charged batteries alone would take the car 40 miles. What happens after 40 miles is magic…

Indeed! No one else would think they can sufficiently propel a 3520 lb car with a 1.4 liter engine for as long as gasoline is supplied. By GM’s own standards the 1.4 liter engine would not provide adequate power for a vehicle of this weight-the GM Malibu at 3415 lbs uses a 2.4 liter engine at minimum.

However, through the miracle of energy conversion, circumventing all the laws of thermodynamics, the little 1.4 liter engine will charge the batteries endlessly and the batteries will power the electric motor and thus provide energy for mechanical power that was beyond the capacity of this same 1.4 liter engine prior to this magical conversion.

The new GM is amazing! Where can I buy some stock?

A mechanical engineer might conclude that the only time the Volt would be adequately powered on an extended trip is when it is driven downhill.

Many economists have already concluded that the extended trip for GM is all downhill.

The reality is somewhere in between.

The GM design has some advantages over the current hybrids. It appears to be a electric car with a gasoline re charger built in.

Let’s say that steady state driving requires 200 units of electricity per unit of time average. Some times like accelerating uphill it may require 600 units. If the generator supplies can supply 250 units It may well work just fine.

Is it any good, I have no idea. Time will tell, assuming GM does not go under next week.

Thanks for the laugh. Or should I be thanking GM?

I’m assuming that the goal is a car that’ll be plugged in for charging and the gas engine will only there to extend the range. But with GM I could be wrong.

We’ll never see the Volt. We may never even see the Camaro.
GM takes years and years and years and years and years to get an idea to market. It was that long after the PT Cruiser hit the market that GM came out with its retro HHR.

Seeing how the modern train locomotives uses such technology, and this technology is really nothing new. Just not cost effective for a car.

my guess is it will work fine in over 90% of the U.S…

In mountainous areas however with miles of hills it could be a problem.

You are correct. The Volt can be plugged in to recharge the battery, or the battery can be recharged by the 1.6-L gasoline engine. GM claims that it can fully recharge in 3 hours on a 240-V line, or 8 hours on a 120-V line.

Kudos! This post just made my day :wink:

Now can somebody explain to me how long those supposed “laptop batteries” that everybody is using are going to last?

My laptop is 17 months old and had a 12 month warranty. After 14 months the batteries started to die.

Is GM also breaking the law of battery life?

I am also wondeirngh what happens to a hybrid if the battery goes bad. Assume at one point you have a 15+ year old Prius and the battery is dead. I would assume that one could simply convert it to gasoline only. Is that a correct assumption?

I am also wondeirngh what happens to a hybrid if the battery goes bad. Assume at one point you have a 15+ year old Prius and the battery is dead. I would assume that one could simply convert it to gasoline only. Is that a correct assumption?

No, but I would bet you will be able to replace the battery pack, likely with new technology batteries by that time.

[b]One Company Is Already Working On This. They Will Offer A Conversion To Boat Anchor.[/b]

“No, but I would bet you will be able to replace the battery pack, likely with new technology batteries by that time.”

I hope that Toyota does not change the exterior of the battery or the power feed parameters so that the battery cannot be upgraded. Not that they would necessarily mean to, but the changes might make good engineering and economic sense.

A 1.4L engine is perfectly capable of pushing a 3500+ lb vehicle down the highway if it is designed correctly. Aerodynamic drag determines power requirement. The extra engine displacement is necessary when you need to pass or climb hill.

That’s the idea of hybrid. It allows a car to get the efficiency of a small engine during most conditions. For the few situation where the small engine isn’t enough, the energy storage contributes.

I know you’re kidding around, but in all seriousness, you only need something like 20HP to maintain speed. Even a tiny 1.0-liter engine could manage that. Think about a conventional car with a 1.0-liter engine driving on a flat surface. Sure, you’d accelerate very, very slowly, but once you get up to speed you can easily maintain it.

Since nobody would buy a car with abysmal acceleration, they add an electric motor that will bump up your ability to draw peak horsepower, say 120HP total, with 40HP coming from the gas engine and the other 80HP drawn from the charged batteries. Once you lift off the gas a little and are demanding less than 40HP, the spare output from the tiny gas motor will be used to re-charge the batteries and prepare you for the next bout of acceleration.

The Volt is not a hybrid. It is an electric car with a paltry 40 mile range due to its robust weight. Do you know of any other electric car of 3520 pounds? So after 40 miles it is still an all electric car attempting to run from the power generated from a small gas engine. At the same time the engine attempts to recharge the battery. Given the variety of terrain conditions this car will be underpowered.
A Civic true hybrid uses an engine about 15% less powerful than the standard Civic.
The Volt keeps on going after 40 miles on a 1.4 liter engine which unlike the hybrid is INDIRECTLY powering the car after mechanical energy is converted to electrical energy and back into mechanical energy.
The weight power ratios are completely inconsistent with any other auto propelled by gas engine, electric motor, or hybrid combination.
Did you think the GM CEO drove the Volt from Detroit? No.

In that case I am wondering: What happens if the battery of a Prius is empty and the gasoline power is needed to propel it forward and keep the auxiliaries working? I would have thought (but I am not technically inclined) that it will just continue driving when the battery pack is broken or does not hold power well anymore. Having to repair this would be a nightmare.

You Are Drawing Conclusions Without Enough Information. You Need To Wait And See If, Or How This Unfolds. In The Meantime, Relax And Go With What You Know.

The Volt weighs that much to provide a battery that can store enough energy to go 40 miles without a charge. If it could go 100 miles without a charge, it would be substantially heavier. Batteries do not have sufficient charge density to allow for long drives without recharging. The Volt’s charge density is better than any currently available hybrid; they all run on an earlier generation battery. That’s why they aren’t plug-in hybrids.

claude9, let me crunch the numbers and demonstrate why you’re perhaps mistaken.

It’s powered by a 1.4L engine, right? With today’s automotive tech, a 1.4’s good for roughly 80-ishHP.

Now, my (totally non-hybridized) Frod Contour gets roughly 27 MPG in daily use, and I average about 30MPH for all the time the engine’s running. Let’s call that approximately 1GPH. Now, an efficient engine can put out 20HP/hr for each GPH–that’s a recollection from my flying days, using engines that aren’t all that efficient.

So, my Contour needs, ON AVERAGE, 20 continuous HP. Given the state of the automotive art, that could be supplied by a 0.35L engine! Now, what with efficiency losses in electricity generation, let’s spec a 0.5L as “just barely adequate.”

Now, let’s consider the “worst possible scenario,” and assume power requirements double under severe conditions. Thus a 1.0L engine. Scaled for weight (2700:3400), we’re darn close to 1.4L (1.26L, actually).

Thus, the 1.4L engine ought to be sufficient to do the job unless truly excessive demands were placed on the car (driving up the continental divide at 90MPH pulling a trailer, for example).