Introduction: DIY Plug-In Hybrid Car

Picture of DIY Plug-In Hybrid Car
This Instructable shows how I built a Plug-In Hybrid Vehicle.

A plug-in hybrid is a car which can run off a combination of electricity (stored in batteries) charged from a wall outlet, and some other fuel, such as gasoline.

This vehicle uses ONLY the battery-electric system to start with, and has manual control over when the other energy source is used, in this case, a propane generator.

Using only electric power, and THEN switching to a hydrocarbon fuel only when needed, is sometimes also called a Range-Extended Electric Vehicle, or EREV.

Think of this car as a poor-man's Chevy Volt or Plug-In Prius.

I already converted this Geo Metro to run on electricity. You can read all the details about that at my ELECTRIC CAR CONVERSION INSTRUCTABLE.

This Instructable will detail adding a second power source to the vehicle to extend its range.

I've been driving this car for about two years now as electric. The only thing I don't like about it is that I find that there are a few too many times where my destination is just a little outside my range, or there is no access to electricity at the destination to be able to recharge while I was there.

Adding the second power system to the car allows me to make trips that I would otherwise need to use a gasoline vehicle for.

In a nutshell - the generator makes AC electricity that powers the traction pack battery charger. The charger passes DC electricity into the batteries. By constantly "topping-off" the batteries, they are kept more full and allow the car to drive farther. The generator is NOT powerful enough to drive the car directly from. However, the generator can continue to run while the car isn't using any battery power, such as rolling downhill, or at a stop light.

So, the smaller, but steady power of the generator provides additional range, while the torque and energy of the electric motor and battery pack give the car good power for acceleration and hill climbing that the small generator engine would NOT be able to provide.

Also, engines running at a steady speed at fairly wide open throttle are MUCH more efficient than one running lightly loaded or at varying speeds (such as in a standard gasoline car.)

See more of my clean transportation projects at

Step 1: Tools and Materials

Picture of Tools and Materials

To get started, we'll need tools and materials for the project.

Also, this project involves AC and DC electricity, Batteries, Generators, Flammable Fuels, Welding, and Power Tools. Always observe all safety precautions. Wear safety glasses, work gloves, and ear protection. Never use tools or techniques you are not comfortable with.

Essentially, this is an electro-mechanical project.

For materials, we will need:
Electric Car
Circuit Breaker
Electric Outlet
Angle Iron and misc metal (check the scrap metal pile!)
Some plywood
Propane tank
Propane Primary and Demand Regulators
Propane hose, hose clamps, and threaded pipe
Muffler and pipe
Electric power cable (6 ga or thicker)
Heat Shrink and misc wiring connectors
12V relay
The Mechanic's manual for the car
3/8ths inch bolts, nuts, washers, lock washers, and threaded rod

For tools, we are going to need a bit of everything:
Ratchet and sockets
Wire Strippers
Work Light
Drill & Bits
Battery Charger
Welder (although bolt-together construction would also work)
Tubing cutter, scissors, or knife
Volt Meter
and assorted other home workshop tools.

I'm a pretty big fan of my Craftsman Cordless Tool set. Two drills/screwdrivers, a work light, a reciprocating saw, circular saw, flashlight, and power stapler all run off the same interchangeable batteries.  I have two chargers and four batteries.
It's great to always have the right tool handy and not have to trip on an extension cord!

Step 2: Generator

Picture of Generator
The heart of this project is a generator, which creates electricity for the propulsion system.

A friend of mine is an RV mechanic. A while back, I got an RV generator from him. It was non-functioning and pulled out and replaced with a new one. He told me that if I could fix it, I could have it.

He was also kind enough to loan me the repair manual!

Since it's an RV generator, it's already approved for use in vehicles, has a remote start feature, and uses a 12V starter with negative ground (just like on any old car!) The generator is a brushless, computer-controlled, variable speed generator, sometimes called an "outrunner". (Because the permanent magnet rotor is on the outside of, and revolves around the stationary internal stator.)

It's a 3400 watt generator - pretty powerful for how big it is.

Going through the manual, I followed all the troubleshooting suggestions, checked the spark, air filter, and oil - all the typical things you would do for a small engine.

Not included with the generator when I got it was the muffler and the propane regulator. It took me a while to find the exact right regulator. It's a fancy Garretson brand, "demand-type" regulator. The regulator prevents any propane from flowing through to the generator UNLESS there is vacuum on the output end. When the generator runs, it creates vacuum, which opens the valve and allows the right amount of propane from the tank to the generator.

I also needed a primary regulator - the one that goes right on the LP tank. It required an 11 inches of water column regulator, which could provide at least 100,000 BTUs. Those are pretty common. I picked one up at the local hardware store for $23. The Garrettson demand regulator was mail-ordered and cost $50, plus shipping.

Much of the time spent on the project was just to get the generator working right. It requires pretty specific regulators, and the fact that it was partially non-functional when I got it meant I had to really learn some troubleshooting. However, a FREE generator was part of the inspiration for this project as the cost was right.

The other thing I like about this generator is that it runs on LP gas! While I would prefer to run the car on electricity (from renewable sources, whenever possible) some hydrocarbon fuels are better than others. The propane burns really clean. This is a four-cycle, single cylinder engine. (Much better than 2-cycles! Ick!) Gasoline is smelly, nasty, and volatile. Also, it goes bad.

In the Chevy Volt, if you never use the gasoline generator, the generator will eventually run automatically, all by itself, just to run some of the gasoline through to help keep it from going bad in the tank. You don't need to do that with propane.

Step 3: Mounting Bracket

Picture of Mounting Bracket
The generator is small enough to fit in the back of the Geo Metro. However, it is designed to hang down between mounting rails in an RV. The flywheel, oil filter, and muffler all are suspended BELOW the bottom of the generator. You can NOT simply set this generator flat on its bottom. It needs to hang.

So, what I needed was a way to mount the generator in the car AND have space below.

The spare tire well is perfect for the lower space required. Now, I just needed a way to span the back of the trunk, so the generator could hang down into the "below the trunk" area.

Looking through my recycling/scrap pile, I found that I had some pieces of old bed frame. It's a very sturdy material. It cuts well with an angle grinder with a cut-off wheel, and it welds OK. It is pretty difficult to drill a hole in though. You will want some high-quality metal-cutting drill bits.

I test-fit the generator to see exactly where it would go in the back. I also measured the depth of the generator and made sure it would clear the sloping "shoulder" of the spare tire well.

The bracket is a capital H shape. I measured the distance across the back of the trunk, and cut two angle irons that size. Then I cut two cross pieces the length of the generator (16 inches) to go between the cross rails.

After double-checking the measurements, I checked for squareness, and then welded the four pieces together.

I then fit the generator into the bracket, between two sawhorses, so I could see how it would hang, and check for any other issues. Good thing I did! The bottom of the generator has an odd shape to it. I had to use the angle grinder to trim just a tiny bit off one part of the bracket for clearance.

I could then mark the center of the mounting flange holes - two on either side of the generator. I pulled the generator out of the bracket and drilled the holes. First, start with a small drill bit, then work your way up to larger sizes, the last one being 3/8th inch.

The bracket also got 3/8th" holes at it's ends where it will bolt into the car.

Once all the holes were drilled, the bracket got a coat of primer and a coat of black paint.

Then, the bracket goes in the car, and gets bolted in. The generator drops right into it and is also bolted in with 3/8ths" bolts, washers, lock washers, and nuts.

Step 4: Remote Start

Picture of Remote Start

One neat feature on this generator is that it has a REMOTE CONTROL PANEL connection on it. That panel is an option for this generator, which allows you to turn the generator on and off from the front of the RV. It also supports an "ON" indicator light and an hours meter.

However, I didn't want to spend money on a special order RV part, (you wouldn't believe how much money they want for it....) and I really just need to be able to kick the generator on.

Fortunately, the repair manual has the schematic for the remote control cable.

By grounding the proper pin on the remote cable, the generator will kick on the starter.

I ran a 14 ga wire from the spice off the ignition to a 12V relay. The leg opposite of that goes to ground (the car body.) When I turn the key the relay is activated. The other two pins on the relay are the wire from the remote cable, and also the ground. When the relay connects the remote cable wire is grounded, and the starter is remotely activated.

A new battery power cable needs to be run to the generator for the electric start. This will provide the 12V+ cranking power for the starter. The 12V negative is through the frame of the generator to the frame of the car, and back to the 12V accessory battery.
The cable needs to be heavy enough to support the amperage required for starting. Since this is only a 220cc single-cylinder engine, I can use lighter cable than would be required for a typical car engine. I looked at the cable on the generator that goes from the starter solenoid to the starter. It was 6 gauge. I used the same weight cable to run 12V power from the battery in the front of the car to the rear of the car, up through one of the drain plug holes in the spare tire well (through a rubber grommet) and to the starter solenoid.

Another great thing about this generator, is that it has a 12V charging circuit. After the generator is running, it charges the 12V battery used to run the starting motor. In my application, this is really handy. On my EV conversion, there is NO ALTERNATOR to charge the battery (because there is not engine to run the alternator.) Nor is there a DC/DC Converter - a device that converts one level of DC electricity to another - for example, 72 volts from the main battery pack to 12V for the headlights, radio, etc. Instead, I simply had a small 12V charger right on the battery. It would trickle charge the 12V battery while the car was plugged in. Most of the time, this was fine. But in cold, dark, winter weather, the 12v battery didn't always perform as well as I would want it to. (For example, dimmer headlights than I would want.)

Now, the generator will take care of the charging the 12V battery. 

Step 5: Circuit Breaker and Outlet

Picture of Circuit Breaker and Outlet

With the generator working, I now need a way to get power OUT FROM the generator.

Even though the generator already has it's own built-in circuit breaker, it seemed like a good idea to have a separate one.

In the RV repair manual, it always showed the power from the generator going to a power center or main breaker box in the RV.

I bought the least expensive breaker box I could at the hardware store, and a single 20-amp breaker. I also picked up an outlet and box to mount it in.

I screwed the breaker box and electric outlet box to a piece of plywood. I then mounted the outlet in the box and installed the cover.

In the car, I mounted the electrical panel vertically to save space. This also faces the electric outlet to the front of the car. For additional rolling testing, I can have the Kill-a-Wall right there to see how many watts the charger is pulling.

The plywood is mounted upright with steel angle brackets, and a triangle of plywood on the end for cross-bracing.

The power cable from the generator feeds through the top of the box, with the hot wire going to the circuit breaker.

I did some early testing on the work bench to confirm everything was working right. An electric space heater makes a swell electrical load.

Step 6: Propane Tank and Mount

Picture of Propane Tank and Mount

The propane tank mounts to the left of the generator.

It needs to be securely bolted down. The only really nice solid mounting points were already used by the generator mounting rack to hold it down to the car frame.

So, I removed two of those bolts, and replaced them with threaded rod. Threaded rod comes in 36" standard lengths. I cut one of those in half to make two 18" long pieces. That's long enough to reach from the car body to the top of the LP tank.

To cut the rod, I threaded on two 3/8ths" nuts and marked a line at the middle of the rod. I put the rod in the vise, but protected the threads by wrapping it in cardboard. I cut the rod with the cut-off blade in the angle grinder. After the cut, I unthreaded the two nuts off the CUT end of the rod. This makes sure the threads keep nice, instead of getting all mangled, and allows nuts to go back on later.

The threaded rod went up through the car body and had a washer, lock washer, and nut on the bottom. Above the floor of the car, it got a nut to prevent the rod from falling back through.

I then measured between the two rods and marked the length. Another piece of bed frame is cut to the measured length plus enough room to drill a hole in either end of the angle iron for the threaded rod to go through.

The bed frame goes through the handle and another hole in the top ring of the tank. Since it's angle, it completely clears the valve.

Adding top nuts and tightening them holds the LP tank securely in the car.

Step 7: Charger and Regulator

Picture of Charger and Regulator

Both the charger and the demand regulator are mounted to the right of the generator.

The charger is a big square box, but needs to have adequate ventilation around it. The regulator is an odd shape, and the mounting holes (two on the bottom, two on the back) are in a strange orientation, making that challenging to mount as well.

This isn't a big car. The suspension mount on the right gets in the way as well, so I built a bracket that raises the charger to make plenty of room for both the charger and regulator.

This bracket is basically just a wood box, make of two pieces of plywood and some 2x4s.

Like under the LP tank and electric panel, the base of it is plywood, cut to fit inside the angle iron frame.

Both the regulator and charger have 1/4"-20 mounting holes. I marked and drilled two holes where I wanted the regulator to go. I put it on an angle to match up how the fuel line would run to it. Two bolts run up through the bottom of the plywood to hold the regulator in place.

I traced out another piece of plywood to match the dimensions of the charger, and then added an inch and a half off the back. That makes it easy to run wood screws through the top of the plywood into 9" tall 2x4 vertical spacers (legs) that connect the top and the bottom of this wood box.

1/4" holes are marked for mounting the charger. Drill the holes, and run 3/4" long 1/4-20 bolts through the plywood to hold the charger.

Wood screws go down through the plywood top into the 2x4s and UP through the bottom plywood into the 2x4s.

The entire contraption - plywood box, regulator, and charger are all put down into that corner of the car. Then I ran a couple of self-tapping screws through the wood into the generator support bracket.

I cut two pieces of hose to fit from the propane tank to the input of the demand regulator and from the output of the demand regulator to the generator's fuel input line.

Both ends of both hoses get a stainless steel hose clamp, tightened down snug.

I like my Handi-Cutter for cutting air hose and the like. It makes nice clean, easy cuts. Far better than a utility knife for this sort of thing.

Step 8: Muffler and Exhaust.

Picture of Muffler and Exhaust.

Converting the car to an EV simplified a lot of things. It totally eliminated the fuel, exhaust, and cooling systems.

With conversion to a hybrid, those now still need to be taken into account.

The propane tank is much smaller than the original gas tank on the car was, and easily fits next to the generator.

This is an air-cooled engine, so there is no need for coolant or a radiator. An integral fan pulls air through the top and exhausts it out the bottom to cool the engine.

That only leaves the exhaust system. Exhaust needs to be routed to outside the car. The generator also did not have a muffler when I got it. Getting the "right" muffler for this generator would mean special ordering one for big bucks through an RV dealer.

I figured that the engine was about the same size as a basic riding lawn mower. So, I just bought a riding lawn mower muffler. That muffler uses a 1" NPT connection. A 3/4" pipe is nearly the exact same size as the exhaust pipe on the generator. Also, this car has several drain holes in the bottom of spare tire well. A 3/4" pipe fits nicely through any of them.

Remember how I originally test-fit the generator in the rear of the car before designing the mounting rack? That was partly to figure out where the muffler would go.

I threaded a 3/4 to 1" adapter into the muffler, and a 3/4" pipe into that. I pushed that up through the spare tire well from the bottom, and then screwed on a 3/4" coupler. That lets the muffler hang, and then tightening it and the muffler to each other clamps the whole unit onto the sheet metal of the car. A 3/4" pipe then goes up to the generator exhaust.

Step 9: The Finished Car.

Picture of The Finished Car.
I will still need to collect data on total electric energy and LP consumed based on various range trips.

In electric only mode, this car has already clocked in pretty consistently at about 130 Miles Per Gallon Equivalent.

Running as a hybrid, it will NOT be as efficient, but I will be able to use the car on many more trips that I would have otherwise driven a gasoline vehicle.

I also like that the generator provides charging for the 12V accessory battery and has some possible use as a winter heater as well. (This car does NOT have an electric rear defrost, but the generator is right under the back window....)

Running in Hybrid mode, the car IS louder than a typical gas car would be, (from the drivers point of view. It's really not that loud from outside the car. )  I may explore completely boxing in the back, including soundproofing.

I also like that I have complete manual control over the generator. In commercially produced plug-in hybrids, the driver doesn't have any control over when the car switches over to run the generator. I like that I can decide when to run it, based on my battery charge and how far away my destination is. 

Overall, I am very happy with the finished project.

Swing by my blog for info on my other clean transportation projects.


urwatuis (author)2015-03-21

This is a cool idea. Are you still driving this car? Did you address the propane tank safety issues? I would think all you have to do to make the passenger compartment safe is A) remove the hatch. B) weld a metal sheet vertically behind the rear seat. C) install a safety glass rear window

virat choudhary (author)2015-03-07

my clz prjct

Bobey (author)2013-05-05

This is crazy but my favorite car is a Geo Metro I know crazy right

rdelaplaza (author)2012-07-31

The whole thing is excellent... BUT talking about efficiency;
you are losing energy in the conversion from 120 VAC through the battery charger. That means part of the energy of the propane you are burning
is becoming heat besides the heat loss of the engine itself.
Which by the way could be used to heat the car in winter.
Generating 120 VAC power with the generator then
using a battery charger to convert it to 12 VDC is not efficient.
You should get a generator which generates 100% of its power at 12 VDC
(there are a few with that will generate 12 volts; problem is that only as a small percentage of the total generated power.. not good)
Then use those 12 VDC to charge the batteries directly, other solution could be using a 120 VAC 3 phase motor (very efficient; with an IGBT controller that will generate 3 phase current to control your motor) and feed the system with 10 x twelve volt batteries in series, that way you will only need a bridge rectifier (converts AC to DC) directly from the 120 VAC generator output to the batteries.
A suitable "regulator" should be used to avoid overcharging the battery pack, there are 100's of circuits out there, to build your own battery charge regulator. That will do the job in the most efficient way.
I'm an Electronics engineer and I'll help you if you want or need any help.

treeology (author)rdelaplaza2013-01-19

Electronics engineers- anyone Help. I have the Range issue on my Zappino electric scooter so i bought a 900 watt generator and hooked it up to a schumacher 72 volt charger (10 amp). But the motor is pulling 1500 watts at governed mode. (3000 watts max). So even going 10 miles an hour i couldnt charge fast enough.. It seems just like mentioned here that i should be able to turn the ac to dc and have more amperage. A bridge rectifier, Im not afraid i will build whatever or cant i modify the charger for more amps output. Speaking of output any input please will be much appreciated. Hell i will reward any savior(s)with some Grgich Hills Wine...Thanks -Treeology

bennelson (author)rdelaplaza2012-07-31

A few good points in there, but to be clear...

I got the generator for free. I did the whole hybridization with existing components I already had.

Also, I would NOT want a generator that puts out 12V, I would want one that outputs a bit higher than the voltage of the battery pack, which can be anywhere from 72 to 144V depending on how many batteries I have in the car.

While creating AC to go to the charger to create DC is NOT the most efficient way to go, I already had both the generator and charger. As for a suitable "regulator" to prevent overcharging, that's built right into the charger as well.

I had considered using a bridge rectifier to convert the output of the AC directly to DC, and running the car at that system voltage, but by that time I had decided that I wasn't really that interested in continuing to run the car as a hybrid, due to noise and space considerations.

Were I going to build a new hybrid from scratch, I would definately consider using an AC motor, IGBT control, etc, etc, but sometimes you can to weigh efficiency VS cost as well.

PS: Actually, I AM considering building a dedicated hybrid right now, but it will be a parallel hybrid rather than a serial hybrid. Still, the electronics and controls will be the most challenging part of the project.

trav997 (author)2012-01-05

If i did this conversion with a truck and put batteries and propane in cargo area would this be legal?

keyguy13 (author)trav9972012-09-09

Yes. people have been turning ford rangers into electric vehicles for years.

tootall1121 (author)2012-05-08

to love4pds. Your idea is self defeating, the power it takes to propel the car is one thing, adding the required energy to propel fans is another, and self defeating. You can't take in more power than the fans would take away. That's one reason electric cars need to be as aerodynamic as possible, to create less drag, and hence take less power to propel. I think teaming an electric motor with a CVT transmission is the way to really go, it would certainly help on take offs, CVT stands for constantly variable transmission, or gears to put it simply. Thus a motor spinning at a given speed would be able to propel the car from a standing start to high speeds without the motor ever changing speeds. What would change is the amount of power required to maintain that speed, but the slicker it is, the better. It doesn't take all that much power to propel a car at a steady fifty miles an hour, but to get there takes torque, and when you go faster than that, the power requirements to do it go up exponentially.

keyguy13 (author)tootall11212012-09-09

Why have a transmission at all? Put a motor at each wheel and you don't need a transmission.

tootall1121 (author)2011-08-30

Henry Ford's original idea was an electric car, but Edison recommended he not do that, with the technology available at that time. The model T's were made so that they could also run on alcohol, since at that time having a still was legal and there were a hell of a lot more of those around than gas stations. The Chevy Volt is doomed to failure. The batteries that would make it work well were bought out by Chevron, and hidden away, even though Toyota had already started building all electric cars with those batteries with good results and reasonable range. The Volt, however only gets 100 miles at best, 40 to fifty miles at worst, and has no self recharging method. Seems to me, a solar panel on the roof and or trunk could recharge the car while people are at work, the major use of many vehicles. However, if the range might only be fifty miles, and many people commute farther than that, it won't do the job... it's also gutless and has a hell of a time with hills, while depleting the batteries faster. Tesla is on the right track, but their methods are still too expensive to be viable. They actually use bunches of laptop batteries.

As to the safety issue, so what? Life is a gamble. So what if a bunch of people get killed in such vehicles? That helps the planet by reducing the population... you won't see me in one, I think there are better alternatives. You can fuel a vehicle with almost anything that will burn, with a few modifications and installing a "smoker" pot. I've seen a truck that runs on wood chips, dry grass clippings, anything burnable.

keyguy13 (author)tootall11212012-09-09

You're completely misinformed about the chevy volt. It has a 50 mile range which has been shown over and over again to be the average distance most people commute in a day. The generator recharges the batteries if you aren't the average commuter or if you are going farther. Considering the price of the vehicale and the enormous savings on gas, the Chevy volt is the best hybrid out there right now. The prius is awesome but only gets about 55 mpg. The volt gets closer to 98 eMpg.

bennelson (author)tootall11212011-08-30

The Volt is designed to run 40 miles on just batteries, and then switches to gasoline power after that. Between the batteries AND gasoline, the driver can go HUNDREDS of miles. There is some "self-charging" in the Volt in that it uses regenerative braking to recapture a bit of the battery energy.

I wouldn't say the Volt is gutless either, it has a sport mode, which gives fairly fun acceleration. I do not live in an area of mountains, but hills were not an issue at all.

I did a video test drive review of the Volt a while back. Please watch it if you have any other questions.

The SL version of the Nissan Leaf has a PV solar panel built in to the rear spoiler. It doesn't charge the traction battery pack, but DOES top off the accessory battery.

Full specs on the Volt and the Leaf are available on their web pages, for anyone who wants to know the actual range, horsepower, fuel economy, etc.

I AM a big fan of "gasifier" vehicles. I have several friends working on gasifier systems for home heating and power generation.
The guys over at Beaver Energy built a really nice wood-gas car:

love4pds (author)bennelson2011-11-01

I am not a car person, so this could be a very stupid question. But why not put a fan in the front to help generate electricity as a turbine would, or even use the one that is on the inside for the water thingy (please don't make fun, cant think of the name of it), while driving to recharge the batteries?

J-Ri (author)love4pds2012-02-20

Having a wind turbine on the front requires energy to turn. Even something small, like a radiator fan (is that the "water thingy" you mean?) in it's original location will use more energy to turn that you get out of it. I believe the best thing to do would be to completely seal off the grille area since very little cooling is required, or leave just enough to provide adequate cooling if heat is an issue.

love4pds (author)J-Ri2012-05-08

I meant as the car is driving using batteries the fan would spin from the wind of the moving of the car. So could that be the energy that moves the fan and charge the battery with that wind while using the battery or engine?

J-Ri (author)love4pds2012-05-08

That's what I thought you meant. It takes more energy to turn the fan than you get from a generator it would turn.

tootall1121 (author)J-Ri2012-05-09

Unless you're driving into a strong wind, yep, that would be the case. The odd thing I don't see any of the electric car makers doing is adding a few solar cells for charging the batteries while it's parked. Granted enough solar cells to run the thing constantly wouldn't be weight efficient nor would they work at night, but most people drive to work, or wherever, then the car sits outside in the sun all day. Even if the solar cells only gave back half the charge used to get to work, it would be worth doing. I think in the eight to twelve hours most people work, a couple of cells in the roof, hood, or deck lid would be able to charge it to full capacity. Why aren't they doing this? Seems like a Duh to me.

bennelson (author)tootall11212012-05-09

Solar cells right now are not efficient enough for a few cells to do much in charging for an electric car.

A full-size, main-stream manufactured EV like the Leaf has a VERY large battery pack, and requires considerable power for recharging. The Leaf has something like a 20 hour recharge time from a 120V 15 amp outlet.

There are a few vehicles out there that do have a small solar panel, but it's for the ACCESSORY battery and or some summer cooling of the car. There are versions of both the Leaf and the Prius with small solar panels on them, but neither is for propulsion.

Don't get me wrong, I'm not saying it can't be done, it's just that it's not practical, due to the expense, size, and shape of the vehicle (PV panels are NOT aerodynamic!)

Vehicles that spend nearly all their time in the sun, use less energy, and are boxier, are good candidates for PV on the roof. There are a fair number of electric golf carts with PV roofs for example. I also know a guy with an electric pontoon boat. He has a fair number of PV panels on the roof of the boat (which shades the boaters from the sun.) He has lake access that is OFF his property, so there isn't any shore power available to him there. The boat is COMPLETELY solar powered, he doesn't even have a wall charger for it.

For most people, solar panels on their garage, with a grid-tie and net-metering payment system is what would make the most sense for a clean energy source. Alternatively, many electric power providers offer some sort of Renewable Energy Program, where you can purchase renewably sourced electricity over the grid.

tootall1121 (author)bennelson2012-05-09

Au contraire, recent advancements have improved them a whole lot. Still, any extra charge would be an improvement over nothing, since most parking lots are not equipped with charging stations.

J-Ri (author)tootall11212012-05-09

They have improved a lot, but it would still be impractical to use them to charge the traction battery, unless by recent you mean in the last month or two. Look at all the protection that is required for the high voltage wires, not for functionality, but for safety. If you had PV panels that were connected to put out the voltage to be able to charge the traction battery directly, they would have tons of insulation around them, and the cars would closely resemble the VW Thing with a roof probably about 4" thick and quite top heavy. If you have the panels arranged to output a low voltage, you would lose huge amounts of energy stepping it up to a voltage that could charge the traction battery. The panel would also be nearly horizontal, which at many times of the year and at most times of the day results in very little direct sun exposure due to the high angle of the panel relative to the sun.

tootall1121 (author)J-Ri2012-05-10

I see you're not up on the latest tech. There are solar panels that are much like cloth now. Not much thicker or heavier than a good denim. I'm not sure of their output, but ANY help would be good. It doesn't take the output you think to charge the batteries some of these vehicles use. In fact, it's better to add charge slowly. Maybe the tech hasn't reached these car makers yet, or maybe it's still too pricey. Everything is when it's the new thing. one thing I have always wondered about, is that solar panels traditionally use the light alone for conversion There has to be some way to put the heat energy to use as well. Oh, by the way, why not enough of a solar panel to keep the battery of a normal car charged? That wouldn't take all that much, but would be a boon to people like me that have vehicles that sit for long periods of time between uses.

J-Ri (author)tootall11212012-05-09

Even driving into a strong wind, you would be ahead by blocking any unnecessary air flow (such as through the grille) in an aerodynamic fashion (such as having a contoured piece of fiberglass or aluminum covering the opening)

You would never get anywhere near half the energy it took to drive to wherever you are parked with PV panels, even if you were parked there from sunrise to sunset and a panel the size of the entire car were pointed directly at the sun all day. As installed in a vehicle, you might have an average of 25% of the panel's rated output due to the angle the panels to the sun. This, of course, assumes that the drive is further than a person in decent health could pedal a bike without breaking a sweat. If you drive 2 blocks, you might get half the energy back, but it's still a small amount.

It would also add a few thousand dollars to the initial cost of the car, and due to the depreciation on a car, would be money thrown away. I doubt that anyone would keep the car long enough for a PV system to pay for itself.

Since it would be foolish to RELY on car-mounted PV panels to get you home from work, one would be much better off setting up a grid tie system at home and charging the car there at night. There, you would be able to have the panels pointed directly at the sun, and sell the energy to the utility company during the day for more money that it costs you at night. Those panels will still be there making you money after the car is gone, and there's no way a van can park next to your house and block the sun.

love4pds (author)J-Ri2012-05-09

oh, got ya. i was thinking backwards.

tootall1121 (author)bennelson2011-08-31

The version I saw the test of was battery only. A prototype, perhaps. Still, the powers that be want it to burn at least some gas, or other fuel they can charge you directly for. What I'm saying is that with the batteries that Chevron bought up, it wouldn't be required to have the gas engine at all, if one was to make sure the car was charged and or charging stations were widely available. If that charge was created by solar or wind power, then there would be no pollution from it at all, no use of non renewable resources. The biggest drawback to battery power without the lightweight, high output batteries is that the vehicle gets heavy having to tote common batteries around. Also, the current electric motors are still rather heavy, weight as we all know is the enemy of mileage. The advance that will change everything either hasn't happened yet, or has been hidden. You used to hear a lot about room temp superconductor research, but the last few years, I've heard nothing about it. Did it get invented then tucked away somewhere? We'll never know. It's actually possible to have a super miniaturized reactor that would power a vehicle pretty much forever, but try getting that past the regulators. Cold Fusion would make that even more likely, and fairly safe. Don't hear much about Cold Fusion these days either, hmmm.

grimdaddy (author)2011-01-09
Your rig is very well designed and constructed. ...But You really need to think A LOT more about safety. Although propane tanks are relatively safe. The tank should either be better protected and/or centrally located in the vehicle. The best option would be an external mounting above the vehicle. The same goes for the combustion chamber as noted by other comments. Isolation is critical to passenger safety. To help you better understand my concern, please do a bit of research on the term BLEVE: Boiling Liquid Expanding Vapor Explosion. It is a nasty and very real possibility in the event of an accident. I have friends who are propane SFX guys and they have related some very scary stories concerning faulty equipment. Please be careful and seriously rethink a redesign for fuel tank protection.

Taranach (author)grimdaddy2011-01-10

OMG It Might be unsafe!!! People, living on the planet earth is inherently unsafe. Yes you try to make things as safe as possible but I am starting to get really tired of the alarmists squealing like a stuck pig on nearly EVERY instructible. The only way to be safe enough for these alarmists is to snuggle into a cocoon with purified water and intravenous feeding and never do ANY thing at all. Excuse me but life itself is a terminal occupation with risks around every corner. Minimize the risks as much as possible and don't do things that are blatantly stupid.

Many people are very correct that if these alarmist had gotten their way through the centuries we would NOT be living as we are today... Don't go outside the cave, you might get eaten! Don't stay inside the cave, it might collapse. Yeesh!!

LancasterPA (author)Taranach2011-07-07

I'm old enough to have used metal monkey bars over concrete in my local parks and never had soft stuff to land in when on the swings with rusted chains. I used metal cap guns with out bright orange plugs in the end too. Putting a Propane cylinder made for a BBQ and not made to be carried inside a vehicle is just stupid dangerous to others. I don't care if this guy kills him self, it's just the kid next door does not deserve his home destroyed because this guy wants to experiment in a housing neighborhood. You can tell from the look that it is even an old cylinder. He does not even have a safety bar above the cylinder. That would protect the valve from being sheared off in an accident. That's not alarmist, it's a reasonable cheap precaution.

Taranach (author)LancasterPA2011-07-07

Considering that I have recently seen playgrounds with just such equipment does not mean anything as to your age... you could be 5 or 25... Point is moot.

As for the rest... pray tell, how do you get that propane tank from the place of purchase to your house? Do you carry it home by hand? No? Perhaps you use a cart or dolly? No? Then golly gee whiz you just put it into your car... and probably far less securely than this guy did... did he put the tank out on the front or rear bumper? No? Gee, it is reasonably protected.... point is also moot.

What about that kid who decides to smash a lighter against the ground with a hammer... does anyone deserve to lose their house from the resultant fireball? Nice appeal of "for the kids"... Point is moot.

Your "reasonable precautions" are just that... if you are so awesomely clever about how it should be done with "reasonable precautions" then Please post your own instructable to show us how to do it "properly.... until then... Point. Is. Moot.

da winksta (author)Taranach2012-04-30

you are moot. this setup is not safe. Taranach, all your Points Are Moot.

there needs to be a division between the generator/propane tank and the passengers compartment. For example look at how RV's have used and mounted tanks and generators for many years.

Taranach (author)da winksta2012-04-30

Been a while since I last looked at this one, had to refresh the memory... Yours is the first that makes any sense as to the "safety" aspect... You are correct that in the pictures there is no separation between tank, generator and passenger compartment, you are also right that it should be addressed... However, did you also notice that he plans to box it in at the end of the instructable? There have been no updates so can't tell if he did.

As to what I said and what I was specifically referencing? Really? Seriously? that is the best you can come up with?

Your point is not "alarmist", yours is precautionary considering what you are working with. I have no problem with that. Suggestions that are proactive and helpful are all good. The others were "alarmist" and negative and indicating that it should not be done at all.. My opinions were valid for the issues raised and statements made. I still stand by them. Yes, sometimes refinements need to be made for various reasons, including safety, and suggestions to make something better are also good, but to not do anything at all because it might be "unsafe" is ridiculous. We wouldn't have 90% of what we have today if nobody ever did anything "unsafe".

Did you also know that when locomotives were first introduced, they were restricted in how fast they could go because "traveling above 30 miles and hour" was deemed unsafe and even hazardous.Guess we should all go back to horse and buggy. No more "unsafe" cars!

DIY-Guy (author)Taranach2011-11-27

Don't forget the dangers of di-hydrogen monoxide (did I get that right?)
Heh heh heh!      ;)

Which part of the cave is the dangerous part again? Front (where the landslides hit one on the head with falling rocks if you venture outside), or the back where you can't dig out after a collapse?

BTW, I know a man who bought a car in the 1950's, converted it to propane and has been driving it ever since. He only wanted to buy one car in his lifetime and he's in his 80's now. The car has over 3 million miles on it and he just does basic maintenance, lube, oil, waxing, etc.

jeditanker72 (author)2012-04-30

Kudos on an impressive project that I cannot even begin to comprehend. Electric cars aren't my thing, but I am glad there are guys like you out there thinking outside the box. One of you guys will be the next billionaire some day. I am only commenting because I saw all the negative stuff. Some people nit pick everything on here. The only safety thing I could see to anyone other than yourself would be to firemen. Maybe if you put a little hazmat placard on the back everyone would be happy.

ben2go (author)2011-01-09

This is a cool conversion.However, it's not legal in any state.With a sealed generator compartment to protect occupants from explosion and a DOT approved tank,it will be half way there.The flooded lead acid batteries put off a gas while charging that is both toxic and explosive.I'm not flaming or degrading your project.In fact I really like it and it would be fabulous in a small pick up.I'm just not sure that you have all the information needed to make this a safe conversion.

bennelson (author)ben2go2011-01-09

This car uses SEALED batteries, not flooded.

The main contactor, and other electrical connections are in a sealed box under the hood.

Dr_Stupid (author)bennelson2011-01-09

It's not the batteries that make it illegal, friend. Transporting a cylinder in an enclosed passenger cabin is against DOT regulations, as is operating a combustion engine in the passenger compartment.

menahunie (author)Dr_Stupid2011-01-09

I agree and any state some one lives in that has vehicle safety inspection as where I do will not pass the inspection with this "conversion".
Also propane is a heavy gas and any leak it will accumulate at the lowest point in the car and then BOOM...
As for your (bennelson) statement of no possibility of sparks you are wrong - THE GENERATOR. Also you have the generator sucking it's air from the passenger compartment as well. I would never ever drive or be in a car like this.. Now if it was in a pickup truck; I would put these items except the propane tank into a truck tool box. Then use a DOT tank mounted either in the bed or under the truck..
This would work except you will have to enclose it in a heavy sheet steel and insulated box with vents to outside and the propane tank mounted OUTSIDE of the car.. The tank will also have to be DOT certified - this certification means the tank will not rupture on impact in an accident if it is hit...
I and others are not putting down what you did; BUT how you did it; it is not a safe conversion..

jpayton (author)menahunie2011-09-16

I agree with what your saying, however this conversion looks to be more proof of concept rather than a final product. On that note if he ever got pulled over in that car they would arrest him and make him tow the car home.

rykonen (author)jpayton2011-10-28

I agree that this is great proof of concept. Now we just need someone to take menahunie's advice and make an Instructable with DOT certified transport so we can all see how to do it legally. Nice going bennelson!

da winksta (author)rykonen2012-04-30

yea this vehicle is badass but has some safety issues for sure. I guess for now... at least make sure the windows are open when the generators running hahahah and good luck!

jpayton (author)bennelson2011-09-16

Sealed batteries still release gasses. IDK about gel but I would assume they probley do to. If your box is sealed then I would just run a piece if 3" PVC under the car with a Computer fan pulling air out. As for the propane tank it is illegal by federal DOT reg's to carry a propane cylinder in the passenger area. Here in maine you can only transport them in a pickup bed. any other method is illegal.

ben2go (author)jpayton2011-09-17

AGM and gel batteries do not release any gas.There is no vents of any type on those batteries.This is all I run in my vehicles because there is 100% no emissions from them.

ben2go (author)bennelson2011-01-09

Ok.Then you are golden there.

J-Ri (author)2012-02-20

Am I the only one that has noticed the wide-spread misspelling, wrong word usage and poor grammar in the posts that criticize by saying it isn't smart to do this? I love irony :)

msihcs (author)J-Ri2012-04-27

I have noticed that too, in particular the HHO guys do an amazing job of BUTCHERING the English language (I suppose we have to accept that, American English butchers every other language)

The funny thing that many people here seem to forget is what Taranach is basically saying, we all die at some point, there is no point in trying to avoid it. I agree with don't do things that are blatantly stupid, but if we do something like is shown here, in the end the world is better for it. Knowing that I am going to die makes me want to do something like Bennelson here is doing and leave this world a better place than the one that I live in.

goldbar2975 (author)2012-02-17

How much is it per mile to run the generator?

bennelson (author)goldbar29752012-02-18

No idea. Never gone through an entire tank yet.
In general, car's that run an internal combustion engine directly with propane are considerably cheaper to fuel than gasoline.

wow..... o.O
Very cool,thank you for sharing!

vov35 (author)2011-10-28

So you don't have a mechanical conection between your gas engine and the wheels? Still quite an interesting project.

What I really want to see is a DIYer emulating toyota's "hybrid synergy drive"... that would be exciting news indeed.

bennelson (author)vov352011-10-28

Nope, the generator only makes electricity!

The Toyota hybrid system is very nice. It relies on a very fancy transmission though. I haven't seen anyone do a homebrew version yet.

On Honda's hybrid system, the electric motor is right on the end of the engine. That really wouldn't be all that difficult for a DIYer to do.

The original Honda Insight really isn't that far from a 3 cylinder Geo Metro engine with an Etek motor on the end of it!

About This Instructable




Bio: Ordinary guy with no special skills, just trying to change the world one backyard invention at a time. See more at: On ... More »
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