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Discussion Starter #1
Hey guys quick question I really want to build my self a good ev but before I will spend 7000-10000$ I want to do my research soo my question is can I build regular ev with warp motor 9" some batteries AND add a small generator to power batteries after I drove the batteries range I got this idea from gm's volt
 

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It has been thought of and it will work...

This may enlighten you a bit...
http://www.evconsultinginc.com/articles/hybridizing_dc_system.html

The problem is that generators are not light weight, even a 6kw one will weigh in at 250lbs, meaning its not really removable (unless you do a trailer design) which means you will be carrying that weight all the time...also, from the link above you see that, 6kw will only be able to support a cruising speed of about 45mph on level ground...Additionally generators are generally not that fuel efficient, I did some math on one and realized it would only give about 30mpg...good for an emergency but not that good for daily use..
 

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If you are doing a pickup you can just put it in the bed when you need it. I have seen them at about 200lbs and $500.
What is the peak kw for the 200lb & 500$ genset?

I think its a great idea for emergency range extension, however I would be concerned with the efficiency of the genset if its planned to be used daily...
 

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The generator is allot more complex than most people expect it to be.

To put the generator in the car you give up / trade it for over 50+ miles of pure battery range ... as the space and weight needed for the generator comes from a reduced battery size.

If you need more than ~100 miles a day often enough ... then it can be worth reducing your range to ~50 miles on battery to have the generator ... but if it doesn't happen often enough it would be better to have the generator as a detachable trailer, so you don't have to carry the dead weight all the time.

Also keep in mind ... not all generators will pass vehicle emissions testing standards in some states.
 

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The generator is allot more complex than most people expect it to be.

To put the generator in the car you give up / trade it for over 50+ miles of pure battery range ... as the space and weight needed for the generator comes from a reduced battery size.

If you need more than ~100 miles a day often enough ... then it can be worth reducing your range to ~50 miles on battery to have the generator ... but if it doesn't happen often enough it would be better to have the generator as a detachable trailer, so you don't have to carry the dead weight all the time.

Also keep in mind ... not all generators will pass vehicle emissions testing standards in some states.
Agreed...A genset that would be easily removable would a real asset to the EV your building...

I have seen many gensets with CARB certifications, additionally since you wouldn't be driving it primarily with the genset you could get it registered without it...and only use it for the infrequent range extending circumstances.
 

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To make a vehicle that runs like a train be remotely efficient you need a high efficiency DC generator 95+% and a high efficiency single speed motor generator turbine like the military uses 40+% efficiency.

You then would need a high efficiency charge controller to hold the genset at its optiminal power output.

Put those together and you will have something that would beat the prius hands down, sadly all of the above are very hard to find in a size that would fit into a normal car.

If you use a normal genset 80% efficiency AC generator + 80% efficiency charge + 15% efficiency motor well you get the idea. Really only good as a backup in case you go too far, not really worth driving the ev with it.

Cheers
Ryan
 

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"beat the prius hands down" in what way? Pollution generated?

Could someone please take their generator to a smog station and get a report on the pollution it generates, and we will compare it to a Prius.

To make a vehicle that runs like a train be remotely efficient you need a high efficiency DC generator 95+% and a high efficiency single speed motor generator turbine like the military uses 40+% efficiency.

You then would need a high efficiency charge controller to hold the genset at its optiminal power output.

Put those together and you will have something that would beat the prius hands down, sadly all of the above are very hard to find in a size that would fit into a normal car.

If you use a normal genset 80% efficiency AC generator + 80% efficiency charge + 15% efficiency motor well you get the idea. Really only good as a backup in case you go too far, not really worth driving the ev with it.

Cheers
Ryan
 

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Discussion Starter #10
I was thinking 1200W 1.5HP or 1400 Watt 3.h.p. Generator that just charge a batteries in emergency situation the 1.5 is not that heavy soo let's say that I have quarter of batteries left I power the generator will my range extend with that small generator???
 

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It really wouldn't be worth it. Probably less than a mile. The only thing it can help you with is you can pull over to the side of the road and wait and wait... At least you wouldn't need a tow truck though unless the highway patrol asked you, what exactly the hell are you doing?
 

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"beat the prius hands down" in what way? Pollution generated?

Could someone please take their generator to a smog station and get a report on the pollution it generates, and we will compare it to a Prius.
If I am not mistaken the generator from Harbor Freight that I linked to is compliant with California standards which are pretty strict. If that particular one is not compliant I have seen a similar one that is in their store.
 

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strict for a generator, will you please take one to a smog station,
and see what readings it gets and report back.
be sure to have it loaded down to its max capacity during the test (not idle)

If I am not mistaken the generator from Harbor Freight that I linked to is compliant with California standards which are pretty strict. If that particular one is not compliant I have seen a similar one that is in their store.
 

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"beat the prius hands down" in what way? Pollution generated?

Could someone please take their generator to a smog station and get a report on the pollution it generates, and we will compare it to a Prius.
The military turbine motors are more efficient than a prius and would emit less pollution per unit of power but as stated rarely come in small sizes.
 

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I was thinking 1200W 1.5HP or 1400 Watt 3.h.p. Generator that just charge a batteries in emergency situation the 1.5 is not that heavy soo let's say that I have quarter of batteries left I power the generator will my range extend with that small generator???
yes it will extend the range... not as much as you might think.

What is the estimated miles per kwh you are expecting to get from your completed vehicle?


For example ... if you are expecting to get 4 miles per kwh ... than a 1,400 watt = 1.4 kw generator would extend your range by about ~5 miles every hour you ran it.

If the battery is dead ... you could limp along at ~5 MPH.

If you have a 50 mile range and drive at 50 mph in 1 hour you use the 50 mile battery and get ~5 Miles more from the ~1.4 kw generator... for a total of 55 Mile range on your battery + whatever fuel the generator consumed in that hour.

For the generator to have a significant range extending benefit you really need to get above 10kw of continuous output... from a unit that will pass vehicle emissions standards... and is small enough and light enough and cheap enough ... and even then ... it is still dead weight on short trips.
 

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yes it will extend the range... not as much as you might think.

What is the estimated miles per kwh you are expecting to get from your completed vehicle?


For example ... if you are expecting to get 4 miles per kwh ... than a 1,400 watt = 1.4 kw generator would extend your range by about ~5 miles every hour you ran it.

If the battery is dead ... you could limp along at ~5 MPH.
Actually it can have a decent effect if the car is used to actually go somewhere without a charge system and set a while. For example, you drive to the grocer and set an hour, drive to the bank set 30 minutes, etc, etc

So it depends on if he is continuously traveling or if he is going from errand to errand and the car has a chance to sit a bit.
 

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Keep in mind if anyone plans to use a generator with a charger, a lot of generators are modified sine wave AC output. Depending on the charger design (it may need to see the peaks of the sine wave which you don't have with modified sw), this may not charge to the correct voltage. So either get a true sine wave generator or check with the charger manufacturer first.
Mike
www.EV-propulsion.com
 

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Actually it can have a decent effect if the car is used to actually go somewhere without a charge system and set a while. For example, you drive to the grocer and set an hour, drive to the bank set 30 minutes, etc, etc

So it depends on if he is continuously traveling or if he is going from errand to errand and the car has a chance to sit a bit.
Agreed.

It could also be used to charge while at work for 8 hours if their is no charge plug available ... In 8 hours the 1.4 kw generator could provide up to ~11 kwh of electricity ... at ~80% net efficiency between charger and battery cycle you would get ~9 kwh of usable battery charging ... if the converted vehicle averages ~4 miles per kwh that would be ~35 Miles restored while working for 8 hours.
 
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