The “range–extended” EV (BEVx) considered

[smkettner]

Actually, 6 kWh Would almost double the 2011-12 LEAF's range, to over 150 miles at 55 mph, wouldn't it?

What's so funny about that?

Hmmm ... how can 6kWh double the range of a 21 kwh battery vehicle ? You can get about 20-25 miles extra.

But we are talking about 6 kW power. This is just one bubble (i.e. the middle bubble) on the Leaf. Just imagine driving with just one bubble of power available (infact one bubble is 8 kW). Even on slight inclines you can only "accelerate" to 15 mph.

If you could generate for 3 hours that would be 18kWh and almost double the battery. 150 miles seems reasonable at 50/55 mph.
Just make sure the 6kW is continuous electric output. Probably lose 10% to DC conversion losses.

Still you only get 150 miles and does not really give much to a real road trip.

 

[edatoakrun]

Actually, 6 kWh Would almost double the 2011-12 LEAF's range, to over 150 miles at 55 mph, wouldn't it?

What's so funny about that?

Hmmm ... how can 6kWh double the range of a 21 kwh battery vehicle ? You can get about 20-25 miles extra.

But we are talking about 6 kW power. This is just one bubble (i.e. the middle bubble) on the Leaf. Just imagine driving with just one bubble of power available (infact one bubble is 8 kW). Even on slight inclines you can only "accelerate" to 15 mph.

If you could generate for 3 hours that would be 18kWh and almost double the battery. 150 miles seems reasonable at 50/55 mph.
Just make sure the 6kW is continuous electric output. Probably lose 10% to DC conversion losses.

Still you only get 150 miles and does not really give much to a real road trip.

In my OP, I suggested an 8 Kw generator, giving more like 180 miles range, at 55 mph. That's "real road trip"(able) for me, but there's no reason a slightly larger or smaller generator could not be optional, on any BEV. I agree that somewhere between 5 and 10 kWh will have optimum market utility.

Higher speed driving will cost a lot of range, as in any BEV.

Remember the additional benefits, of having an on-board hydrocarbon fuel source, for a cabin and/or battery pack combustion heater, which could also be offered as a stand-alone option or otherwise "pure" (non EREV) BEVs for cold-climate markets.

 

[evnow]

If you could generate for 3 hours that would be 18kWh and almost double the battery. 150 miles seems reasonable at 50/55 mph.

Are you saying, one would start the genset as soon as the trip starts with a fullly charged Leaf ?

At 5 m/kwh, I think we can get 150 miles, in that case. But, I'd say 60 mph is the minimum for inter-city travel. 4.5 m/kwh is a more likely efficiency (esp. if dragging a genset). That would probably allow for 2 hours (and a bit more) of driving.

I was looking at a real range extender that gets switched on when turtle hits, so that you can make it to a charging location.

 

[smkettner]

BTW, you can't get 150 miles @ 50/55mph. With 21kWh battery, what range would you get @ 50/55mph ? 90 miles, if you don't use climate.

If you generate from the start you will get extended generator time as the total distance and time is extended.

I use 50 mph and 6 kW for easy math. 150/50 = 3 hours = 18 kWh. 18 + 21 = 39 kWh total available over the 3 hour period.
Maybe 39 kWh would get you more than 150 miles and more than 3 hours at 50 mph. Still not much of a road trip.

You don't wait for turtle mode to start the generator.

 

[evnow]

Maybe 39 kWh would get you more than 150 miles and more than 3 hours at 50 mph. Still not much of a road trip.

Looks like my upgade & your replay were cross-posted.

Yes - for a real road trip, you need a nice 30kW genset - so that you can recharge the car within an hour. This will let you drive for several hours without stopping. That 30kW is actually quite tiny by ICE comparison - it is like a small 40 hp engine.

 

[edatoakrun]

Maybe 39 kWh would get you more than 150 miles and more than 3 hours at 50 mph. Still not much of a road trip.

Looks like my upgade & your replay were cross-posted.

Yes - for a real road trip, you need a nice 30kW genset - so that you can recharge the car within an hour. This will let you drive for several hours without stopping. That 30kW is actually quite tiny by ICE comparison - it is like a small 40 hp engine.

As I posted earlier this AM:

A major advantage of a lower output (5-10 kWh) range extender, whatever type of engine driving the generator, is the ability to utilize it efficiently over a greater proportion of total duration of the your trip.

Remember your BEV is still going to have to limit total charging to protect your battery, so your car will have to either shut down the generator or decline regenerative braking, whenever the total of these two charge sources becomes too great. And of course, there is no “range–extending” occurring when the generator is not usable.

On highway driving, where the car rarely generates much energy from regen (except when descending long steep grades) it will probably be a very rare event for the car (or the driver) to have to “turn off” the generator with a 5-10 kWh output range extender, and the energy lost to friction braking will be negligible.

The larger output generator you install, the more it’s efficiency (and probably it’s life) will be reduced by increased start/stop cycling.

It will also be bigger, heavier, and more expensive.

As far as the EREV on board charger is concerned, small is beautiful.

 

[AndyH]

Rinspeed Dock+Go for Smart ED

http://www.rinspeed.com/pages/cars/d+g/pre-d+g.htm

http://www.technologicvehicles.com/...dockgo-by-rinspeed-the-range-extender-trailer

 

[DaveinOlyWA]

WOW!

 

[JRP3]

I'm sorry but that is just silly.

 

[evnow]

I'm sorry but that is just silly.

Why - if someone made a trailer like that for Leaf, I'll rent it from time to time. Infact, that would probably allow us to go all EV instead of one car with an engine.

 

[scottf200]

I'm sorry but that is just silly.

Why - if someone made a trailer like that for Leaf, I'll rent it from time to time. Infact, that would probably allow us to go all EV instead of one car with an engine.

Wouldn't you think the extra wheels would affect steering and drivabilty on that backpack solution. Plus the extra tire friction wasting energy.

As well for trailer solution for EVs, the main issue would seem to be it can be more of a pain to park and certainly to back up. Interesting concept tho. I recall reading on the Volt they added a trailer to help simulate climbing a mountain on flat ground (that is the natural drag of extra wheels/weight and probably artificial drag they added).

http://editorial.autos.msn.com/article.aspx?cp-documentid=1149282" onclick="window.open(this.href);return false;
Chevy has hooked up a towing dynamometer to the Volt and simulated a grade of 2 percent to 10 percent, which the car has been able to handle. No, the Volt will no be equipped to handle towing, Chevy says.

 

[JRP3]

I'm sorry but that is just silly.

Why - if someone made a trailer like that for Leaf, I'll rent it from time to time. Infact, that would probably allow us to go all EV instead of one car with an engine.

The problem is it's vehicle specific, so instead of a generic trailer that could be used on any EV that one is designed for a single vehicle, raising it's cost and limiting it's usefulness. I also think it might induce some weird handling issues. I think one of those single swivel wheel trailers would be a better idea, still eliminating any backing up issues but allowing any vehicle to use it. Or just a small standard trailer, they aren't really that hard to maneuver.

 

[walterbays]

Jim Motavalli's book High Voltage describes the Audi E-tron. It sounds like the Volt as originally described, a series hybrid with a small gasoline engine in series to extend the range. As opposed to the Volt as finally delivered, a series/parallel hybrid with a large gasoline engine prompting endless debate whether it's more of a PHEV or more of a range extended EV.

The E-tron A1 has a 60 hp electric motor giving 31 miles of electric range, supplemented by a 20 hp Wankel gasoline engine which gives another 124 miles of range. The "only" problem is that the E-tron is a concept car. The smaller higher performance E-tron R8 is scheduled for limited availability in 2012. No word on even a limited edition of the A1.

 

[AndyH]

I'm sorry but that is just silly.

Why - if someone made a trailer like that for Leaf, I'll rent it from time to time. Infact, that would probably allow us to go all EV instead of one car with an engine.

The problem is it's vehicle specific, so instead of a generic trailer that could be used on any EV that one is designed for a single vehicle, raising it's cost and limiting it's usefulness. I also think it might induce some weird handling issues. I think one of those single swivel wheel trailers would be a better idea, still eliminating any backing up issues but allowing any vehicle to use it. Or just a small standard trailer, they aren't really that hard to maneuver.

But is this really a problem? Considering that there is no standardization among EVs at this point, and no 'factory authorized' way to inject electrons between the battery and the motor, this is the only type of concept I'd expect. Not to say that EVs won't continue to evolve...

Trailers introduce their own challenges - including those with castoring wheels. The person with the trailer skillz that would benefit from or require a swivel would not likely have the 'trailer awareness' to keep the trailer safe in a parking lot...at least the first couple of times.

 

[JRP3]

Well even the body extension makes the vehicle longer so someone not used to it could still back into stuff. There is only so much you can do for people. A trailer genset should be easily adaptable for different vehicles, this body graft thingy will not be.

 

[evnow]

Well even the body extension makes the vehicle longer so someone not used to it could still back into stuff. There is only so much you can do for people. A trailer genset should be easily adaptable for different vehicles, this body graft thingy will not be.

I was really talking about the generic trailer rather than the particular.

Even then, I'd think Leaf being the most dominant EV, would probably get a good particular trailer that is optimized for it. So, I'd welcome it. Something is better than nothing - at this point.

 

[evnow]

As well for trailer solution for EVs, the main issue would seem to be it can be more of a pain to park and certainly to back up.

Yes - for sometime it would be like driving a u-haul ;-)

Hopefully the rear view monitor helps a bit.

 

[Ingineer]

I can confirm my range-extender/quick charge trailer is easy to drive with. It is relatively easy to back up as long as it's done carefully, but the trailer is also so light, it's super-easy just to unhook it and wheel it anywhere you need. It can easily be done with one hand in fact.

-Phil

 

[N952JL]

I still think three small microtubro genset built into a 18" x 60" x 24" box would be able to slide into a tow hitch receiver. Each genset would be 8kW so the three combine would be 24kW. Not enough to run without the battery at 70mph on the interstate but enough to give you a very nice range.

 

[JRP3]

I'd have to think a single 24kw unit would be more efficient, and cheaper.