Can I use a GENERATOR to power an Electric car directly?

[dcb]

Originally Posted by Geebee

A series hybrid that only uses the motor say 8% of the time its running is a hell of a lot more efficient than say a current Prius....

I'm not sure you understand how the prius or series works then( or I don't).

[jamesqf]

Originally Posted by Nerys

my 82 Goldwing only gets about 30-35mpg then again its 25 years old and has a giant 1.1liter 4 cylinder engine and masses 900 pounds :-)

But my 2000 Insight has a 1.0 liter, 3-cylinder engine, weighs a bit over twice that (1840 lbs IIRC), gets 71.2 mpg (real world average over about 85K miles) - and I can take the dog along with me :-)

Except in Arizona nevada and kansas etc.. there are no FLAT roads on this planet...

Flat roads in Nevada? Nevada State Route 431 - Wikipedia, the free encyclopedia sure don't look flat to me :-)

[Geebee]

Originally Posted by dcb

I'm not sure you understand how the prius or series works then( or I don't).

The current gen Prius recharges its battery by the ICE, it can't possibly be as efficient/FE as a series hybrid such as the Volt that will only use the genset for extended range.
Te rest of my comments apply if they are both plugins, even if you had the same size battery pack in both the parrallel will still have a larger ice, transmision to suit the ice and a more limited layout, plus the ICE will be using its entire rpm rang thus getting variable efficiency.

[dcb]

That comparison is still a few sandwiches short of a picnic.

[Geebee]

I am all ears as to why.

[dcb]

The generator in a series setup is maybe %70 efficient SOURCE, the motor maybe %90 SOURCE. So just to get from the ICE to an output shaft is about %63 percent efficient in a series setup, ALL THE TIME, even when cruising down the hiway for many many miles and hours at a fairly constant speed. The ICE cannot bypass these losses EVER in the serial setup. I am thoroughly convinced that the volt sucks for this reason!

If you parallel that ICE, you can choose the gearing for peak efficiency on the hiway (or at least within %10 of peak SOURCE) over an rpm range of thousands. And if done with chain/sprockets it can be %98 efficient SOURCE. So you wind up with a drivetrain that is %98 efficient at peak and say %88 efficient before you (being the good energy manager that you are) kick in the electric motor and optionally declutch/shutdown the ICE (unless you need both for this next hill).

It isn't rocket surgery You will need to run up to 1/3 more gas through your series setup to get the same range. That is horrible. But that is what happens when lawyers and bureaucrats make engineering decisions.

[Geebee]

Real world ICE drive train losses.http://www.fueleconomy.gov/FEG/atv.shtml
They look a bit dodgy but a lot closer than the ones you stated.

Your own motor references showed motors over 95%, complete genset "Overall efficiency of a Polar DC genset is between 75 and 85%"
And for the average user in a series hybrid the ICE will rarely be used as it is range extending only.
This was a few minutes searching not the best out there.

Just found this for the Prius

[dcb]

Originally Posted by Geebee

...
And for the average user in a series hybrid the ICE will rarely be used as it is range extending only....

Why do you think the series hybrid is unique in this case?!? A parallel range extender would only be used when needed too.


But if you build it in, then at least half of "the average user" will use it a LOT, and you have extra weight (motor + generator) to carry all the time. If it is a 5th wheel spring loaded thing you put in your tow hitch receiver for longer trips, it won't get used a lot (or if it plugs into the existing driveline somehow).

[dcb]

Also those losses for the engine apply to the genset as well, so don't think it is an automatic win. An engine in a parallel setup can be maintained within %90 of peak efficiency when backed by a battery pack and motor, and actually has a peak efficiency far greater than the serial version.

Methinks you have not carefully examined the losses in the serial setup.

[Geebee]

But 90% of 36% without drive train losses, a series is easier to build and I suspect will ultimately be cheaper and lower maintainence.
Also hasn't research shown that the majorty of drivers drive a relatively short distance on a daily basis, which would favour a plugin electric or a range extended series hybrid.
In the above senario a Volt will annihilate a Prius on FE and still be able to do the longer trips as required.
If you go and look on the Prius chat forum you will see some very poor highway milages.
Would it be possible to do a parallel in say an Aptera, drivetrain issues and engine positioning becomes an issue without comprimising aerodynamics and space, again effecting FE.
We could go around in circles but the future will show which stays and which doesn't.