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Discussion Starter · #1 ·
I want to build a solar/hybrid pickup, attaching the electric motor between the tranny and the rear end. My first question is, can the gas motor and the electric motor be used at the same time? The gas for getting going, and the electric for just cruising? I'll need recommendations for the smartest combos of truck/electric motor, with the easiest marriage of the electric motor to the drive train. I have no problem making driveshafts, done that.
 

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What you're proposing is a parallel hybrid. Yes, in any parallel hybrid you can run either power source (engine or electric motor) by itself or both in combination. In this case the electric motor is on the output side of the transmission (an arrangement now called a "P4 hybrid"), so if only the electric motor is working you need to consider whether that is okay with the transmission - typically automatic transmissions will not lubricate properly if the output shaft turns without the input shaft (from the engine) turning.

The "Balance" hybrid system of a decade ago from Azure Dynamics (which went bankrupt years ago) used this configuration, adding a motor inline with the shaft behind the transmission of a Ford truck.
Azure Dynamics and Utilimaster converting Ford E-Series into hybrid commercial vehicles
 

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Just a reality check... if solar panels on the roof are the only source of charging, you're only going to be cruising on electrical power for minutes a day.
 

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...
wouldn't the opposite be more efficient? electric to get going, then gas for cruising?
I agree - the normal operation of a non-plug-in hybrid is to meet general power demand directly with the engine, supplementing it with electrical power for acceleration and recharging with regenerative braking by using surplus engine output when demand is low.

Based on power output capability, someone might reason that the more powerful engine is used to accelerate, then the smaller added electric motor is used to cruise. The issue is the energy supply: there's lots of fuel to run the engine, but not much energy in a battery, so logically you need to cruise on that fuel (meaning running the engine) and only meet brief demands from the battery (meaning using the motor).
 

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Discussion Starter · #6 ·
Thanks so much to all, I can see I chose the right forum. Your cruise/electric tips sound good, it will be fun to play around with it. Solar is just because the sun is free, and the panels don't cost too much. Sitting in a parking lot all day should amount to something. Otherwise, plugging into home is on the menu, especially now that there are so many offers to go solar at home, too!
I'm curious about the parallel setup, will have to give the physics a look. Gas motor only thru the electric requires the electric to be locked? Maybe no problem, the electric motor may be solid, input shaft to output shaft. Gas motor and the electric, the electric is going to act like overdrive, add to the motor rpms and torque. Electric only will try to turn the tranny backwards? I know it's all been done, so the answers are out there.
My first need is finding good deals on electric packages and good match-ups of electric motors and trucks.
I saw the Azure setup had two driveshafts, probably to protect the tranny's tailshaft bearing, which isn't engineered for the weight of an electric motor hanging out there, wringing around. Trannys always wiggle around a bit, and a separate driveshaft to the electric motor solidly mounted is probably wise. Those splines and u-joints forgive a lot. The second driveshaft from the electric motor to the rear end just has to be long enough to do it's job, allow the rear end to do it's thing.
So, the first thing is finding a good match-up of truck and electric drive. Any help is appreciated. And, PS, I plan to have solar film on roof, hood, and camper top.
 

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I'm curious about the parallel setup, will have to give the physics a look. Gas motor only thru the electric requires the electric to be locked? Maybe no problem, the electric motor may be solid, input shaft to output shaft. Gas motor and the electric, the electric is going to act like overdrive, add to the motor rpms and torque. Electric only will try to turn the tranny backwards?
Not quite. You can (as in the Azure Dynamics Balance system) just use a motor with a shaft that sticks out both ends of the motor, so the motor shaft (which is just one solid part) forms one part of the truck's driveshaft. When the motor is not powered, it just spins like a plain piece of shaft; when it is powered it adds torque to whatever is coming from the transmission. The speed of the shaft from the transmission to the motor and the shaft from the motor to the axle are the same, because they are just sections of the same shaft.

The available and practical type of motor which turns most freely when no power is applied is an induction motor; that's what the Azure Dynamics Balance used, it was the popular type of motor for EV conversions for years, and it is still what Tesla uses in the Model S and X.

An overdrive is an auxiliary transmission that steps the speed up from input to output, with a corresponding decrease in torque. The motor is not an overdrive; it is a torque booster. When the gas engine is not running the transmission output shaft still needs to be able to turn (the transmission must be in neutral), and the motor is adding its torque to the zero torque from the engine and transmission.
 

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I saw the Azure setup had two driveshafts, probably to protect the tranny's tailshaft bearing, which isn't engineered for the weight of an electric motor hanging out there, wringing around. Trannys always wiggle around a bit, and a separate driveshaft to the electric motor solidly mounted is probably wise. Those splines and u-joints forgive a lot.
No, trucks like that normally use a driveshaft in two sections, just to avoid any shaft section being too long to be just supported at the ends; just look under a big straight truck (not a tractor for semi-trailers) the next time you walk or drive by one. Even some much smaller vehicles use shafts in two sections, for various reasons of joint types and component packaging, but cars and pickups do usually just use a single section.

True, you can't just mount the motor on the transmission tailshaft housing without supporting the motor. Mounting it between two shaft sections like the Balance is just easier than making custom housings to mount it directly to the transmission. If you are familiar with 4X4 systems, the Balance motor is mounted like a divorced transfer case; the alternative is to mount it like a married transfer case.

The second driveshaft from the electric motor to the rear end just has to be long enough to do it's job, allow the rear end to do it's thing.
Correct: if anything is inserted between the transmission and the axle then the final shaft section to the axle must be kept long enough to keep joint angles reasonable and to allow the splined section to plunge enough to accommodate suspension travel.
 

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My first need is finding good deals on electric packages and good match-ups of electric motors and trucks.
I think your first step ought to be to ask yourself; "what is the end goal?" I am sure there is a way to build what you are describing, and If I was going to have anyone's help in researching and designing it, it would be Brian_'s :). I am just not sure what you hope that this system is going to actually do. It will likely be too expensive to ever save you money, and I dont know anything about performance, but I suspect if you want more power there are much easier (and cheaper) ways to get it (like putting in a bigger gas engine). I am not an expert on hybrids, but to get a boost to efficiency, you would need to be managing the ICE to keep it running at peak efficiency, shutting off when electric power is sufficient, and also charging your battery when that is needed. Without some serious modification to how and when the gas engine runs, I am not really sure what you are going to gain, or how you are even going to effectively control the throttle.

Now dont get me wrong, if this sounds like a fun way to spend tens of thousands of dollars, by all means, go for it! I will point out that you should temper your expectations of the solar roof. If you park on a nice south facing hill and get 5 hours of full sun, you might be able to squeeze out 10 miles of pure EV driving range... Anyway, if you decide it is a fun idea just for the hell of it, I will gladly follow along and offer any insight I might be able to share. Batteries and solar are two of my favorite topics, drivetrain questions I will leave to the experts :)
 

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I think your first step ought to be to ask yourself; "what is the end goal?"
Absolutely!

I am not an expert on hybrids, but to get a boost to efficiency, you would need to be managing the ICE to keep it running at peak efficiency, shutting off when electric power is sufficient, and also charging your battery when that is needed. Without some serious modification to how and when the gas engine runs, I am not really sure what you are going to gain, or how you are even going to effectively control the throttle.
While a very simple control system for the electric components is possible and practical, I agree that doing this well enough to really benefit is difficult. One reason that I linked the article about the Balance system is that it describes the extent of modifications that Azure Dynamics made to make the overall system work well enough to justify the costs, beyond simply adding a battery, controller, and motor.

I have spent some time considering a similar addition to my motorhome (which is like a pickup but much bigger), primarily for nicely controlled regenerative braking on descents which would recover energy to assist in climbs (with a bonus energy storage system to eliminate generator use when camped); however, I don't believe that it would be close to cost-justified, the weight increase would certainly reduce any hill climbing performance benefit, and the the control system would be relatively crude. Carrying enough battery to enable electrically powered travel for any significant distance, and mechanically modifying the vehicle to make it reasonable to drive with the engine shut off, would be impractical.
 

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Discussion Starter · #11 ·
Not quite. You can (as in the Azure Dynamics Balance system) just use a motor with a shaft that sticks out both ends of the motor, so the motor shaft (which is just one solid part) forms one part of the truck's driveshaft. When the motor is not powered, it just spins like a plain piece of shaft; when it is powered it adds torque to whatever is coming from the transmission. The speed of the shaft from the transmission to the motor and the shaft from the motor to the axle are the same, because they are just sections of the same shaft.

The available and practical type of motor which turns most freely when no power is applied is an induction motor; that's what the Azure Dynamics Balance used, it was the popular type of motor for EV conversions for years, and it is still what Tesla uses in the Model S and X.

An overdrive is an auxiliary transmission that steps the speed up from input to output, with a corresponding decrease in torque. The motor is not an overdrive; it is a torque booster. When the gas engine is not running the transmission output shaft still needs to be able to turn (the transmission must be in neutral), and the motor is adding its torque to the zero torque from the engine and transmission.
Thanks for simplifying things for me, I tend to over-complicate things. I should have realized the motor is straight through. I hope to find the most popular system and do that. I don't need to re-invent anything, want to keep it KISS.
 

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Discussion Starter · #12 ·
Absolutely!


While a very simple control system for the electric components is possible and practical, I agree that doing this well enough to really benefit is difficult. One reason that I linked the article about the Balance system is that it describes the extent of modifications that Azure Dynamics made to make the overall system work well enough to justify the costs, beyond simply adding a battery, controller, and motor.

I have spent some time considering a similar addition to my motorhome (which is like a pickup but much bigger), primarily for nicely controlled regenerative braking on descents which would recover energy to assist in climbs (with a bonus energy storage system to eliminate generator use when camped); however, I don't believe that it would be close to cost-justified, the weight increase would certainly reduce any hill climbing performance benefit, and the the control system would be relatively crude. Carrying enough battery to enable electrically powered travel for any significant distance, and mechanically modifying the vehicle to make it reasonable to drive with the engine shut off, would be impractical.
Thanks, all for the wake-up call, it really helps. I built two total solar cars for Villanova University a long time ago. One racer, one commuter. I didn't build it all, just helped the students and did what they couldn't. I was impressed that the cars were total solar. Now I see hybrids in the parking lots, quietly pulling away. Around here, Bristol, Tennessee, it's popular to modify trucks for off-road, so modifying is very popular. They have weekly car shows downtown for folks to show off their work. I'm really hoping to be able to build a hybrid as cheaply as possible, sell it and then build another. Profit is the motive to be honest. I'm hoping the uniqueness will make the sale.
There seems to be a lot of DIY hybrids out there, so I'm hoping a control package is available. I've tried to imagine how to co-ordinate the gas pedal with the electric motor control, sure seems like a tough one. I'm an inventor, and can usually work out problems like this, but I am sensible enough to know when I need help. It's being done, so I'm just saying 'show me, please'.
 

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I would buy a stock GMC Suburban, Tahoe, 1500 hybrid

then proceed to canbus snoop to see if you can keep the engine off

once complete I would add battery capacity and a charger.

Other ways of making a hybrid truck are body swap scenarios, the case you provide has only been done once or twice with s10’s and the result didn’t have much EV range.


 

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Profit is the motive to be honest. I'm hoping the uniqueness will make the sale.
If that is your goal, you might want to try and find the buyer before you start. I had to look them up, but I guess hybrid trucks are a thing already.

"The hybrid option can be had on any F-150 crew cab for a somewhat reasonable $2500 to $4495, depending on the trim level. "


It is also telling that Ford only managed to squeeze an extra 4 mpg out of their system, despite what I am sure is a very sophisticated engine control system.

Personally, I dont think building a hybrid truck is a bad idea, but I think trying to build one for sale is probably not going to pan out the way you want it to.
 

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Discussion Starter · #15 ·
Thanks for the input, Carl, I'll take it into advisement. If it doesn't sell, I'll just use it as a Sunday driver, that's when the car show is downtown. I can pick up a little truck for a song, and will shop carefully for the hybrid package. I'll document it for this site, compare with other builders.
I'm not surprised Ford couldn't get extra miles per gallon, no solar package, so the only gain would be from regenerative braking, which is marginal. If the Ford F150 was plug-in I'm sure they had a small battery package and that is a big heavy truck. The reason I'm using a truck is to accommodate half a dozen car type batteries, some motors are 75 volts. Put them in the back and still have room for the average load.
 

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Ford and Dodge hybrid trucks are only mild hybrids, I wouldn’t expect alter-motors with start stop to do much and actually if they would have converted said truck to FWD with a manual transmission they likely would have gained just as much economy with no alternator motor

GM did have at one time full hybrids which could be modified with work to be plug in
 

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Discussion Starter · #17 ·
This forum has been up for years, and there are tons of pics. I sure would hope a favorite system for parallel hybrids has been found.
 

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If that is your goal, you might want to try and find the buyer before you start. I had to look them up, but I guess hybrid trucks are a thing already.

"The hybrid option can be had on any F-150 crew cab for a somewhat reasonable $2500 to $4495, depending on the trim level. "
The F-150 is just the latest hybrid truck. There is a current mild hybrid system available on Ram trucks, the most capable hybrid pickups ever built were the 2009-2013 GM full-size pickups and SUVs with the 2-Mode system, and GM also did a sort of mild hybrid from 2004 through 2008.

It is also telling that Ford only managed to squeeze an extra 4 mpg out of their system, despite what I am sure is a very sophisticated engine control system.
That's actually a massive improvement.
 

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This forum has been up for years, and there are tons of pics. I sure would hope a favorite system for parallel hybrids has been found.
But this forum is primarily for battery-electric vehicles, not hybrids. In my limited time here, it seems that most hybrid proposals as expressed as "I want to add these components; how do I do it", rather than the more likely route to success, which would be "I want to achieve better economy (or performance, or whatever), what would achieve that?". As a result, they typically fizzle out when they turn out to be more work or less practical or of less benefit than desired.
 

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Discussion Starter · #20 ·
Thanks, Brian, I thought there was some kind of disconnect there (EV joke). I'm looking at the 'unique' factor to make the hybrid truck attractive. The locals appreciate good work, love pickups, enjoy modifying. Instead of going taller, wider, noisier, with huge tires I'm hoping for smarter.
 
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