Diesel truck and generator in one?

I had another silly idea.  I'm considering putting solar on the house and going off grid for various reasons.  I can't get enough solar in the winter due to clouds and trees but can get plenty in the summer.  So my plans had been to get a generator for the winter and let it sit idle all summer.

Brainstorm...  Could I get a diesel engine that could do two jobs?  In the winter it generates electricity every few days to fill up the batteries.  In the summer it hangs out inside a 1936 Ford pickup.  At both times it runs on homemade biodiesel or filtered veggie oil.  I wouldn't need the generator in the summer and I wouldn't need the sexy truck in the winter.  

This leads to all kinds of questions...  What kind of diesel engine would work as both a generator (long periods at a fixed/ideal rpm) and a motor vehicle (revving and such).  It would have to be able to fit in a truck.  I'd probably leave it in the truck and just rearrange the driveshaft to power a generator head.

I don't know enough about all this so it likely won't work for about 8 different reasons.  Please let me know what those reasons are before I waste too much brainpower on it. Thanks!


*I don't own a 1936 pickup yet but this is what they look like

Hi Mike;
Fun Idea!  You could make it work but I don't think you want to.

To run that very pretty truck (that I doubt you can afford) you would want a 4cly  Cummins motor known as a 4BT
It comes in quite a bit of off-road equip such as air compressors, larger generators, small bobcats, and lots of other things.
This is a popular installation for jeeps or other off-road toys.  All in all a really good motor.

The diesel you want to charge your house system is a 3 cly that is often found in portable light plants.
Much more economical, plenty of power, and in fact purchasing a used one at auction and leaving it as a light plant gives you portable lighting!

If you did want to use an old truck.  In the past, a rear wheel was removed and a belt drive attached in its place.
Using the transmission and a hand throttle (an early version of cruise control) to determine the spin speed.

Thanks Thomas!  It probably wouldn't be a "very pretty" truck but it depends what I'd find.  I'd have to find a project truck that has a good body and frame and no engine.

So why wouldn't the Cummins engine work for generating power?  If the 3 cylinder one is more economical, in what way is it more economical?  Better fuel to watts ratio or something else?


*maybe it would look more like this...

diesel electric, like a railroad locomotive.

Well, Mike, I don't know the Fuel to Watt ratio on those guys.
The 4bt is a turbo engine and will run at 70 mph in a 75 Ford full-size bronco.
The 3 cly is nonturbo (I think) very small and compact.  It has a generator built-in that you would plug a battery charger into for your house batteries. Plus you get a portable light plant.  It will not get any mileage at all but I'm guessing it would run a fair bit longer than the 4BT would.

On a more realistic side.   Generator load changes as batteries charge.
A generator needs to automatically adjust with the load.
A belt drive or a shaft drive in a truck would only run at the speed you set it.
Not very efficient, but you could make it work.
 

A cummins 4BT would weigh too much for that truck.
It's also expensive and becoming a hard to find engine.

A VW TDI diesel would have more power than the engine that truck came with
it's easier to find,
can be made to operate without a computer (M-TDI)
and would be cheaper to operate.

Problem I see is the truck would use a transmission and the generator would be direct drive.
Unless you are using the engine to run electric motors for power to the wheels.

My suggestion... Get A Tractor

I just recently purchase an over 30 year old John Deere 870. It had only 88 hours on it somehow and was in mint condition/kept inside a garage the whole time.

The thing came with an 8gal fuel tank and a naturally aspirated 3cyl engine with 28hp and a lot of torque. The engine is liquid cooled, direct injected, and (Most Importantly) has an engine governor on there that will keep the RPMs constant as engine load varies. Also, the engine is made by Yanmar in Osaka, Japan. A top-of-the-line engine.

That governor is going be essential to generating power as the load is constantly varying. Lawn mower engines have these as well.

They make generators that run off of the rear PTOs on tractors

Also, that little diesel engine is insanely efficient. I put 5gal of diesel into that thing a few weeks ago. During that time, I used the tractor to rebuild a few sections of fence line but using a hole digger with a 9" auger to dig about a dozen holes 4' deep(often multiple times since the old posts/concrete were in the way). I also used the tractor to rip out several posts, and a tree stump... and then level the entire area with a blade. Then just a few mins ago I finished bush hogging about 4AC of field from about knee to waist high... down to 8".

During all of that time the fuel gauge went from being just 1/16th of an inch above the 3/4 mark... to now sitting at the 3/4 mark. Awesome!!!

You would be able to use the tractor for work during the Summer... but use it for power during the Winter.

Honestly... that tractor being as old as it is... was not much more than my Toro Titan 60" with MyRide. It came with multiple attachments as well. I would not want to use it as a lawn mower though unless I had a finishing mower deck. Still... the Zero-turn cant be beat for normal lawn in tight spaces (fruit trees and fence)

My Toro doing the same work as an air-cooled, carbureted, gasoline motor that is brand new... would have taken twice as long and burned through at a minimum of 10gal of gasoline doing just 2AC of the same pasture. To be fair though it would have been cutting much shorter and chopping it up much finer as well.

Here is an example of a PTO driven generator...

https://www.electricgeneratorsdirect.com/Winco-W10PTOS-PTO-Generator/p12098.html

I have absolutely no idea what her set up is, but a friend of mine uses her car for power to her house. Her son set it up because she lives in an area with frequent, sometimes days long power outages. I don't know if she's charging batteries or just running power to crucial appliances. Probably the latter. She's been doing it for years, though.

I picked up an Auragen 20kw generator that was mounted in a utility service truck. I was going to mount it on front of the Cummins that is in my skoolie but haven't yet. It was mounted on a Cheverolet 350 so still fiddling with bracketry and pulleys. It is actually quite small for 20kw genset and VW diesel could easily run it.
https://aurasystems.com/auragen.html