Electric pusher

[ron22]

Possalby a dumb idea., I have alot of them.
Would it be possible to build a "trailer" with an electric motor and batteries? Have it geared for the freeway (60-70MPH) using as small of motor as possible just to maintain speed. Then use my CRX engine to get up to speed. Once at speed turn off the gas engine and turn on the electric motor. I could even use the trailer to continue the rear sloop of the CRX. The weight of my CRX HF is less than 2000lbs.
Am I wrong that it takes most of the power to get the weight moving and up to speed?

[thisisntjared]

that all depends on how fast you plan on going...

[MetroMPG]

I wondered about something like this (except for urban use) when I wrote this article:

All I want for Christmas is a plug-in hybrid pusher trailer

[ron22]

I saw the one you talked about MetroMPG but it was the opposite of what I was thinking. Yours was for around town mine is for freeway. Most the others I saw when searching were for electric cars and most of the time it seemed they were to just charge the batteries .

[MetroMPG]

I think you'd have a hard time making an electric pusher trailer for highway use because energy demands are so much greater at highway speeds.

Unless you have a source of advanced batteries (nicads or li-ions & associated management / charging), the trailer would have to carry too much lead to make it practical.

[Bill in Houston]

People usually think in terms of "electric car, gasoline pusher" because of range considerations.

I sort of get where Ron is going in that with a small car he could cruise with maybe 11 hp of electric power. Whereas for driving around town, 11 hp would be pretty low.

To me the issue is that in town you only need propulsion for short bursts, while on the highway it is a constant long-term demand. Of the two following scenarios-
1-30 hp electric car with 20 hp gas pusher for the highway
or
2-50 hp gas car with 20 hp electric pusher for the highway
-it seems that the one with the electric pusher would end up needing more batteries/weight. BUT, it could still be a useful rig. I need to think about it some more.

[GasSavers_Ryland]

how about just a smaller gas engine pusher? something direct drive? if I was to do an electric pusher I would want it for in town, regenerative breaking, stop and go trafic.
in talking to owners of electric vehicles, they all say that they try to stay off the highway as much as possible because it kills their range.

[MetroMPG]

That's an interesting idea Ryland.

As for max range for DC EV's, I'd guess it's probably at the lowest constant speed in a gear where motor RPM is roughly 3000.

The reason the Milburn & Baker electrics from the early 1900's had such long ranges (50-60 miles) is because their max speeds were 20 mph, so average speeds were even lower than that

[ron22]

Originally Posted by Bill in Houston

People usually think in terms of "electric car, gasoline pusher" because of range considerations.

I sort of get where Ron is going in that with a small car he could cruise with maybe 11 hp of electric power. Whereas for driving around town, 11 hp would be pretty low.

Yes that was my thinking. I would realy only need to gear the motor for one speed and could use as small of motor as posible.

To me the issue is that in town you only need propulsion for short bursts, while on the highway it is a constant long-term demand. Of the two following scenarios-
1-30 hp electric car with 20 hp gas pusher for the highway
or
2-50 hp gas car with 20 hp electric pusher for the highway
-it seems that the one with the electric pusher would end up needing more batteries/weight. BUT, it could still be a useful rig. I need to think about it some more.

Since I already have a 60 HP car I was leaning for option 2

[rh77]

I've thought of something similar on-board (to turn the rear wheels on a front-drive car).

The trailer looks to keep it simple regarding the drive mechanism.

Concerns:

How stable is a pusher-trailer with a single pivot point at 60 mph? Highways here are pretty lumpy and have undulations, especially before and after bridges.

I do quite a bit of high-speed driving (cannot be avoided -- schedules to/from the airport and no light rail YET). To work and back, the speeds are slow enough with congestion to help with drag considerations.

However, a gasoline/diesel or CNG/LNG-powered pusher (either on-board or trailer-bound) is intriguing. Have alternative fuels been considered? The 5th wheel idea has been implemented (on-board vehicle pusher), but seems complicated with an added suspension component.

I have plenty of room in the hatch area for such extra equipment. How would an on-board generator feeding electric traction motors in the trailer work? (more of a serial design such as a locomotive). The trailer would need some weight for traction. Further, on brakin, could they be turned into juice to charge the ICE's batt for restart? Ahh, the possibilities...

RH77