EV conversion vs. installing PHEV kit on a hybrid

[mechman600]

Originally Posted by cRiPpLe_rOoStEr

Anyway, instead of just converting a random used car to all-electric I'd consider to bolt a portable genset making it a parallel-hybrid, then it won't be so compromised mileage-wise (and you could still use it at home in case of power shortage).

Unfortunately, a "portable" genset with enough power to move the car down the freeway (~30kW) isn't going to be so portable. It will fill most of the engine compartment up. Or all of a huge trunk - and in a trunk it will be so noisy that you won't be able to hear yourself think, not to mention cooling issues and the like. It took GM a lot of engineering magic to accomplish this with the Volt. Also, powering the wheels with a generator, batteries and motor with is very inefficient compared to driving the wheels mechanically. That's why on the freeway the Volt's engine can be geared to the wheels.

[Checkthefuse]

30kw is a bit extreme don't you think? EPA claims 20 average drive HP at highway speeds= 14.9kw. But even a 15kw genset would require a trailer. Sorta reminds me of the Tzero.

As for your options... I think the biggest considerations are your wife and children. If we figure a low level of mechanical sympathy from them, your "high cost" EV would probably have to be "very high cost" to offer the turn-key amenities expected. You would have to modify 10 blow dryers for heating alone.

I am in a similar conundrum, and am leaning towards PHEV conversion of a Toyota product (read as Lexus). All the benefits of Toyota engineering, but a bit of the fizz from the PHEV kit.

[Daox]

Originally Posted by mechman600

I wondered about this because I knew the EV speed limit was for protection. Isn't the EV limit for the latest Prius 62 mph?

The EV limit for the OEM PHEV Prius is 62 mph. I believe it is regeared to allow this (not 100% sure). The regular Prius is geared differently.

[vskid3]

Toyota Prius - Power Split Device
A little simulation to help explain the way the Prius' (and I believe all Toyota and Ford hybrids) transmission works. The EV mode top speed is there to protect MG1, which has to cancel out the rotation of MG2 to keep the engine from spinning.
The max speed of the Escape in EV mode is about 40MPH. The '09-12 years have a slightly bigger engine, but the software was redone so the engine will turn off more often. It seems like I have to beg my '06 to go into EV mode sometimes, so a '09-12 would probably make better use of the PHEV system. I looked into doing a PHEV conversion to my Escape, specifically an Enginer 4kwh kit. It would take at least 5-7 years for it to break even, and that's if it would double the overall average mileage (very unlikely).

I would do the EV conversion if you think you can make something that your wife would be happy to drive. But keep in mind, a stock Escape or Camry Hybrid will at least match the mileage your Matrix gets. Then you'll be able to decide if the PHEV conversion makes sense for you. Its really up to you.

[mechman600]

Originally Posted by Checkthefuse

30kw is a bit extreme don't you think? EPA claims 20 average drive HP at highway speeds= 14.9kw.

I live in BC where most highways are mountain roads, especially the roads I frequent. 14.9kW will not even come close. A 7% grade requires ~60kW in a 2800 lb car. After 10 minutes of that, my battery pack, controller and motor will be overheating big time. And then by the time my 14.9kW genset catches up, I have long since encountered another huge hill.

Originally Posted by Checkthefuse

You would have to modify 10 blow dryers for heating alone.

HA! Good one.
The real reason for the blow dryers is that I didn't feel like spending 5 days R&Ring the eBooger's heater core. I think dealer SRT time is something like 11 hours. No thanks!

EDIT: Wait - you live in Langley, BC! You of all people should know better!

[cRiPpLe_rOoStEr]

Originally Posted by mechman600

Unfortunately, a "portable" genset with enough power to move the car down the freeway (~30kW) isn't going to be so portable. It will fill most of the engine compartment up. Or all of a huge trunk - and in a trunk it will be so noisy that you won't be able to hear yourself think, not to mention cooling issues and the like. It took GM a lot of engineering magic to accomplish this with the Volt. Also, powering the wheels with a generator, batteries and motor with is very inefficient compared to driving the wheels mechanically. That's why on the freeway the Volt's engine can be geared to the wheels.

A lot of factors influence the results of a parallel-hybrid setup. I've already seen some gensets fitted with 2-stroke gasser engines which could fit easily in tight spaces. Also, for an increased efficiency hub-motors can be considered since there are no parasitic losses from a transmission.

[mechman600]

Originally Posted by cRiPpLe_rOoStEr

A lot of factors influence the results of a parallel-hybrid setup. I've already seen some gensets fitted with 2-stroke gasser engines which could fit easily in tight spaces. Also, for an increased efficiency hub-motors can be considered since there are no parasitic losses from a transmission.

Ewww....2-stroke? Are you allowed to say that on this forum?

The hub motor may be the answer. It frees up a LOT of space. But there are no hub motors (at least in the DIY market) large enough.

Kelly has one, but it is only 7kW.
http://kellycontroller.com/car-hub-m...7kw-p-711.html
Even four of those (28kW) wouldn't be enough.

EnerTrac makes one for a motorcycle with a continuous rating of 10kW/30kW peak, but unfortunately it is meant for a motorcycle so it is spoked with a motorcycle rim.
Electric Motorsport EV Parts
It could possible be retrofitted for automotive use, but that's beyond my capabilities.

Unless someone knows of a readily available hub motor, that idea is moot.

Another problem is a charger. The largest Manzinita charger (PFC-75) is only good for around 10-12kW. And that thing is over $4K. Maybe if one could source a large DC generator and come up with the ability to throttle it to maintain a safe battery voltage we would be away to the races. But that is WAY beyond my abilities. Actually, I think the guy who wrote "The Zero-Carbon Car" and made a diesel/electric/hybrid thing out of Miata used a DC generator in that exact way.

If only I was smarter....

[cRiPpLe_rOoStEr]

Originally Posted by mechman600

Ewww....2-stroke? Are you allowed to say that on this forum?

Not every 2-stroke is evil, and with some developments such as direct injection they can still be more efficient and less pollutant than a comparable 4-stroke, and remain lighter and more compact.

The hub motor may be the answer. It frees up a LOT of space. But there are no hub motors (at least in the DIY market) large enough.
(...)
EnerTrac makes one for a motorcycle with a continuous rating of 10kW/30kW peak, but unfortunately it is meant for a motorcycle so it is spoked with a motorcycle rim.
It could possible be retrofitted for automotive use, but that's beyond my capabilities.
(...)
Unless someone knows of a readily available hub motor, that idea is moot.

With 40kw/120kw there might be enought power to a compact car, (even a Prius ). There are better ones, such as those from Protean Electric (70kw each if I remember correctly), but then it's big money. Anyway, you would need a controller for the hub-motors...

[Xringer]

I looked for used 2012 Prius C models and only found a couple in New England.
They were very low mileage and were priced very close to the cost of brand new..

BUT, when I checked the 2012 Plug-In Prius there were 11 used cars on the NE list!

For some reason, it seems like the Plug-In Prius cars are being turned-over faster..
(Or, a lot more plug-In cars are being sold).
Maybe people found it was too much trouble to mess with the charge cable..?


That leads me to think you should be on watch for a used Plug-In Prius..
By next summer, there might be some good prices on the 2012 models.

[gd420mj]

Here is a great explanation of how the 2nd gen Prius transaxle works and another mention about why its limited to 41~2 mph. :

Same user has other hybrid system explanations. Very imformative.