Turn Car Engine into Home Generator

Has any body heard of or know someone who has converted a car motor into a home generator?
I have an old car with a destroyed transmission and hate to see the rebuilt engine go to waste.
What are some detailed physical/electrical drawbacks to doing this?
I realize it would save time to buy a generator from the hardware store but I enjoy being resourceful and working on projects like this.

Any direction is much appreciated

It would be a whole lot less work to buy and install a used transmission in the car, or alternatively sell the engine, possibly in the car. If a prospective buyer can hear the engine start and run, that is a very good selling point.

You can do this,but it will not be very efficient,if one would do this and make it into a “TOTEM” system,then it would work,why bother?I like "oldtimer’s suggestion better.
The car engine isnt really optimal for this application.

You need to find an appropriate sized AC generator or alternator, about 75 kW (equals 100 HP) rated at a good RMP for the engine, say 3000 FPM. Or gearing to change the 3000 RPM of the engine to the rated RPM of the generator.

However, searching for “generator” on the web is difficult, as the term also applies to motor-generators.

That alone is a complicated design.

Then feedback controls to control the throttle of the engine based on the output voltage AND frequency of the generator, which should be 120 volt 60 Hz.

An even more complicated design.

I’d bag it, you could spend years on this and fail.

Not a good idea. You will save a lot of time and money by just buying a home generator and replacing the transmission on your vehicle. The cost of running a vehicle engine alone would put me off this plan. I do have a good friend that runs a sawmill with a straight 6 Chevy engine though. He’s had that configuration for over 20 years and it still operates. The secret to his fuel economy is the one barrel carburetor sitting on his intake.

And when you’ve finally got it built, it won’t be very efficient to run. Large generators in general are thirsty. This one will be more so.

Your power generated would be quits expensive. At $3.00 per gallon you get about 15,000x7=105,000 BTUs or 105,00/3440 KWHs= 31 KWH energy for $3. A gas engine is about 30% efficient, so your cost/KWH will be about 300/31x1/.3=32 cents per KWR.

I’d sell it and be done with it.

My brother in law used the engine from one of our old cars to power a welder for field use. That was a better application.

You might want to expand your vision for possible uses for a car engine:

Around these parts, a V8 snowblower would be very handy. :wink:


Whatever you do, be certain to install a transfer switch. A transfer switch switches your home’s power system from the main supply line to the generator. Without one, some poor lineman trying to fix the cause of the power outage is likely to get zapped from the power from your generator. When your generator is powering your house, the house and generator MUST be disconnected from the main line.

Although it could be done, it sure seems that it would be an inefficient use for all the gas it would take for that outcome.
Plus, as a home generator, STORING gasoline for all the time it takes to wait out an emegency situation needing it, might end up in a no-start condition for your power plant due to old gas. You could hope that fuel stabilizer would be the answe,r but only time will tell.

This is why a diesel generator makes sense for the long wait between uses.

An ICE could be converted to run on natural gas. If I get a generator, it will be powered with methane since it is piped to my house.

If you mean use the alternator ON the car engine to generate electricity for the home, don’t bother, it isn’t big enough to produce enough energy.

If you mean to use the engine to turn a generator big enough run your home, that’s gonna be expensive and difficult like the other posters say.

$10,000 will buy you a dandy natural gas or propane generator that has all the bells and whistles WITH a transfer switch. Way better than fooling with keeping gasoline or diesel around for emergency power.

Generac throws an ad on several cable chanels when bad weather is in the area. Their ads indicate that the machine runs a self test regularly by starting the engine and running it several minutes. Maybe it “texts” the homeowner if a problem is indicated. When properly installed those systems disconnect the house from external power while the generator runs and disconnects and shuts off when service is restored. I imagine such a system is quite expensive.

I did see a generator powered by a four cylinder Willys Jeep engine back in the early 1950s. We were visiting relatives and these relatives had friends that had a cottage on a river. The cottage was not near any power lines. Much of the equipment in the house did not require electrical power. The range and refrigerator were LP gas powered. There was a big Stewart-Warner console radio that was battery powered. The generator was,in a shed remote from the cottage, but there was a turn switch in the cottage that said “Off-On-Start”. I think the well pump had an electric motor, but there was a water storage tank. I suppose the Willys Jeep engine speed was governor controlled. It has been about 63 years ago since I saw the set-up, and I was 10 at the time, and was only there once, so I don’t remember much else about the set-up.
I do have a gasoline powered, generator that we bought when an ice storm came through 10 years ago this past March. We toughed it out one night, but the next night we went to my wife’s office that had power. Her boss came in with her family with the same idea. Her boss called her brother miles away and found that he could get generators. She asked my wife if we also wanted a generator and my wife said yes. They left about 8:00 p.m and returned after midnight with 2 generators. However, by the next morning our power was restored–ws are on the same big loop with WalMart and Lowes and the power to these stores was restored ASAP. I did use the generator to power sump pumps at the church I attend to keep the basement from flooding and have used it to power a welder and my electric chain saw, but essentially it wasn’t a worthwhile purchase. I run it a couple of times a year and keep fresh gas for it,but have not had a,power outage long enough to need it.

@Rod Knox. I actually have Generac backup generator. Mine runs off natural gas. It does indeed fire up and run for about 10 minutes once a week. Mine doesn’t text me or anything though. It has an LCD display/menu on the unit. I’ve had it for about 3 years now and it’s been flawless. Maintenance is pretty minimal. If you live in an area that gets hit with hurricanes every other year, it’s nice to have. A couple years ago after a hurricane blew through, I was without power for 9 days. (Va Power said it would be 3 days before the power was back on), that was the last straw.

I believe you can buy the generator and electronic controls alone to be used with the power take off on a tractor. What you’d save who knows? But make it mobile and treat it as a tractor power take off and go from there. You do need to be very careful with the transfer switches or you’ll kill someone. Plus, those of us who have been exposed to emergency generators know that maintenance and monthly testing is essential. I just have a small one that I could use to survive if I had to but power has never been off more that four hours that I can remember. Now my cousin has a cabin in Colorado that has no access to any utilities but he uses sun power.

Agree with oldtimer-sell it and buy a tractor if you must.

I have seen local ads for 10,000 watt 18 horse power generator selling for $750. It’s hard to imagine buying a seperate generator and the hardware to get it connected to an automotive engine for that amount.

We have an old flathead running an arc welder 4 or 500 amp for thawing frozen water services, Now I have a home generator for bank a in the breaker box 3400watt cost $300, of course will turn of main feed to prevent electrocuting linemen. No ac but in the winter the furnace will run. Backfeeding through outside outlet.

A simple method that could indeed be useful in an emergency situation when no other electrical power at all was available would be to just use the existing alternator already on the engine as the generator, and purchase an inverter to provide 110 VAC. No a good way to power up an entire house, but you could at least run a few lights that way.

I would get an inverter-generator, in fact I have one. The main advantage is that the engine does not have to turn 60 revolutions per second (3600RPM) ALL THE TIME to generate 60 HZ alternating current, the generator actually generates DC which is then inverted electronically into 60 HZ ac.
The main advantage is that the engine can power a light bulb running at idle speed and it revs up according to the load demand. This means you don’t have a ridiculous standby fuel consumption when the only load on the generator is light bulb or a small radio. Also, these units are very quiet, making them welcome in RV parks.