Diesel Electric conversion for our trucks

[EricBu12]

WOW! What a discussion my original Idea has turned out to be. . now gensets and capacitors with rheostats?. .

Keep the Ideas coming. . eventually someone might just figure it out. . I drive truck for a living and have little time for research. . I have lots of time on my hands for Thinking up crazy ideas like this. . lol

 

[Gary - K7GLD]

Gary... you really know how to be a party pooper.

ACTUALLY, it's a lot closer to reality - the basic idea may be OK with a different platform, but this particular base vehicle under discussion is pretty far out of reason or practicality - lots of effort, time and $$$ to end up with less than what you start out with...



BUT, dream on...

 

[mberry]

Why couldn't you leave the stock stuff there? What I mean is, if traveling at 65 or 70MPH only uses 10-15% of the peak output of the 5. 9 or 6. 7 Cummins, why couldn't you just put in place a small diesel-electric system to operate at the 15-20% range of the stock Cummins? Then when you need that power, the "main" engine starts and runs through the traditional in-place drivetrain that shuts off when the driver and/or conditions dictate it. You could put an elecrtic motor directly on the differential housing/rear yoke with a mechanical or electric coupler to disconnect the main driveshaft when running in "electric" mode and it would also power the accessories and provide power steering capabilities like an electric motor on the PS pump, A/C compressor etc... Have a couple/few/whatever of large capacity batteries to help get the load going while driving in town or stop and go if needed. Use the main engine/drivetrain while towing or needed and use the diesel-electric combo for charging the batteries and providing emergency power to your home or power to your RV while parked. Just an idea and would eliminate a lot of the extra weight of batteries and such.

 

[Gary - K7GLD]

Why couldn't you leave the stock stuff there? What I mean is, if traveling at 65 or 70MPH only uses 10-15% of the peak output of the 5. 9 or 6. 7 Cummins, why couldn't you just put in place a small diesel-electric system to operate at the 15-20% range of the stock Cummins? Then when you need that power, the "main" engine starts and runs through the traditional in-place drivetrain that shuts off when the driver and/or conditions dictate it. You could put an elecrtic motor directly on the differential housing/rear yoke with a mechanical or electric coupler to disconnect the main driveshaft when running in "electric" mode and it would also power the accessories and provide power steering capabilities like an electric motor on the PS pump, A/C compressor etc... Have a couple/few/whatever of large capacity batteries to help get the load going while driving in town or stop and go if needed. Use the main engine/drivetrain while towing or needed and use the diesel-electric combo for charging the batteries and providing emergency power to your home or power to your RV while parked. Just an idea and would eliminate a lot of the extra weight of batteries and such.

AH, but you miss the MAIN point of this particular thread - we're not talking about a *commute vehicle*, but rather, a WORK vehicle that is commonly used at or over it's rated GVWR, such as hauling construction materials, or towing heavy loads up long and steep grades!



NOW, if we want to SWITCH the target vehicle to something that IS a commuter or grocery-getter, THAT is a different story altogether... :-laf



Ayone here stop to think or ask, if it was cost or fuel efficiency effective, why aren't the 18 wheelers ALREADY using it?



Could it be, that it would take up MOST of the cargo area, just to carry the batteries? :-laf



.

 

[Little Bill]

The biggest issue is the conversion of energy from one state to another. You lose at every step. And an ICE engine is the worst loser in the equation, about 30% efficient. If you take that mechanical energy and convert to electric, you lose another 10%. Run it to an electric motor (convert it back to mechanical energy, which is where you started), another 10% loss. If you're generating AC power and want to store it in batteries, you have to convert to DC which is a big loss. If you generate DC directly then the losses are even greater and you're limited in generator options to lower kW outputs.

You can not beat the energy of conservation law or the laws of thermodynamics. If it takes x hp to push an 8000 pound truck down the road at 60 mph, then you have to supply x hp. There are many ways to arrive at x hp. The most efficient method is the most direct.

You may speculate that a battery based, all electric vehicle is more cost effective. Maybe, if you are only using it travel a few miles a day. But the 'plug in' costs end up being similar to cost per mile of the same vehicle equipped with a small ICE engine of the same hp. Remember, you're taking a hit on that AC to DC conversion. And then there is the issue of very limited range. Go back to the Volt specs I posted earlier. If you only go 40 miles it appears you have done that for free, only run on batteries. If you drive it continuously until the 11 gallon tank is empty, you get a mpg rating of 53. Throw away all the battery junk and the mpg rating is 50. But if you plugged into the gridto charge the batteries to get that initial 40 miles, then the 3 mpg gallon improvement is simply smoke and mirrors. If you have your own solar or wind generation system and you plugged in there, then you would realize a 4/5th gallon of free travel, assuming you have already recovered the cost of installing those systems.

If you want high mileage, get a Prius or TDI. If you tow or haul real stuff, get a diesel truck. You'll have issues if you try to convert one into the other.

 

[Drewhenry]

Work vehicles Diesel Electric

Dangit all!



I'm now all excited about Mutiple Unit operation of these diesel electric pickups! Anybody know what MARS lights are? How about ditch lights while we are at it, a real snow-plow bumper a super charger to go with the turbo, 26L brakes anyone? Gonna have to get a horn! I like 5 chimes!! And a bell too!!



Sorry to get off track, no pun intended!



Andy

 

[EricBu12]

OK, I had a different thought.

If Electric Motors are such high torque monsters, what size or HP of motor would be needed to get like 600 #/feet of torque hooked to the axle yoke?

Would like a 50 or 100hp Motor make 600 3/ft of torque? If so, then the power needs for a Generator would not be as high.

 

[Little Bill]

200 hp

torque = (5252 * hp) / rpm

 

[Gary - K7GLD]

200 hp



torque = (5252 * hp) / rpm

YUP - and don't overlook all those conversion losses Bill pointed out earlier - and also don't overlook the fact that a WORK vehicle's average power draw will be considerably higher than a commute or grocery getter vehicle...

 

[Alphacowboy]

I have thought about adding two smaller drive motors to each side of the rear axle. I have a bent axle that I would be willing to sacrifice as the prototype. Basicly my thought was to do an electric assist system. Getting the generator power in the mix along with a regular driveling would be challenging. But anyway, this is my idea:



[]=motor=@=motor=[] The axle shafts would go all the way through as they do now, but would be splined where the aux motors would be. These motors would be part of the axle housing and would assist the typical drivetrain. They would add no extra sprung weight to the vehicle as they are on the axle, and not the chassis. Different way of going about a "hybrid" type of system.