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Robert
Custom made bra fitter
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21st Post Thu Aug 21st, 2008 07:15 pm | |
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Bob Of Burleson wrote: "The Chevy Volt can be driven 40 miles in electric-mode using 16kW of lithium batteries, before its small one liter engine is engaged."
Sounds to me like you could keep moving as long as you've got gas in the tank. Wouldn't that 1-liter engine be the Volt's main engine and the other one referenced an even smaller one for the batteries?
It says the 1 liter engine will not turn the wheels.
If 16 kw will take you ~40 miles, as that would be dependent on what speed you were dirving, starts and stops etc. and if you knew what hp the engine was then you could convert from hp to watts and tell if the engine is powerful enough to keep the batteries charged under constant driving conditions. 746 watts per hp.
But they don't say.
What they are doing is;
Take an engine that is .3 efficient. If it turned the wheels, then that the end of the story. Except that on deacceleraation you have a regenative motor used as a brake that charges batteries. The efficiency there is .3 * .9 * .8 = .216
They way they say they are doing it, using the engine to charge the battery, you get
.3*.8 * .9 * .9 *.8 = .156
That is engine to battery to motor back to motor/generator to battery. Same cycle as before, i.e. getting the engine into acceleration and back to the batterys.
They are getting 1/2 of what they could be getting if the engine did turn the wheels.
But it also says that the motor and engine are in series. It seems kinda unbelivable that they would try to make an efficient car and use the less efficient method.
There is no reason to go from engine to batteries to motor to wheels, when you could go directly from engine to wheels. The hybrid still gains on the conventional set up because braking is charging the batteries.
A gas electric hydrid gains over a gas engine in two ways. The regenative capabality of the motor/generator, and the fact that the electric motor is .9 efficient while the gas engine is .3. That's it.
Last edited on Thu Aug 21st, 2008 07:22 pm by Robert
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The state has become a modern idol whose suggestive power few men are able to escape. ~ Albert
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Robert
Custom made bra fitter
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22nd Post Thu Aug 21st, 2008 07:31 pm | |
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This is why I say you could turn every car on the road right now into ra hydrid, if you added a regenative motor.
The motor would act as a brake / generator and charge batteries.
Hook the motor on the drive shaft with a pully, and use it to push the vehicle down the road.
What you gain over just the gas engine turning the wheels is that you turn the deacceleration back into power.
You recover .9*.8*.9 = 57.6% of the energy that the gas engine put into acceleration.
It should increase gas milage by ~ 30%.
That is throwing away 27% of it, just to be conservative, because you don't do all your driving in town, and on the highway you don't do much deacceleration so the hybrid don't help you much there.
Last edited on Thu Aug 21st, 2008 07:35 pm by Robert
____________________
The state has become a modern idol whose suggestive power few men are able to escape. ~ Albert
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Bob Of Burleson
...And the smell of gunsmoke
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23rd Post Thu Aug 21st, 2008 07:50 pm | |
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"In the event a driver forgets to charge the vehicle or goes on a vacation far away, the Volt would still get 50 mpg by using the engine to convert gasoline into electricity and extending its range up to 640 miles, more than double that of today’s conventional vehicles."
Automotive.com
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Robert
Custom made bra fitter
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24th Post Thu Aug 21st, 2008 08:41 pm | |
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| That would indicate that the engine will keep up with the batteries.
____________________
The state has become a modern idol whose suggestive power few men are able to escape. ~ Albert
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Bob Of Burleson
...And the smell of gunsmoke
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25th Post Thu Aug 21st, 2008 10:20 pm | |
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| Yep, and I wonder if you'd lose any power since you'd still be running off the electric motor.
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Bob Of Burleson
...And the smell of gunsmoke
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26th Post Fri Aug 22nd, 2008 02:13 pm | |
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A Better Way To Make Hydrogen From Biofuels
ScienceDaily
Researchers here have found a way to convert ethanol and other biofuels into hydrogen very efficiently.
A new catalyst makes hydrogen from ethanol with 90 percent yield, at a workable temperature, and using inexpensive ingredients.
Umit Ozkan, professor of chemical and biomolecular engineering at Ohio State University, said that the new catalyst is much less expensive than others being developed around the world, because it does not contain precious metals, such as platinum or rhodium.
"Rhodium is used most often for this kind of catalyst, and it costs around $9,000 an ounce," Ozkan said. "Our catalyst costs around $9 a kilogram."
She and her co-workers presented the research Wednesday, August 20 at the American Chemical Society meeting in Philadelphia.
The Ohio State catalyst could help make the use of hydrogen-powered cars more practical in the future, she said.
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