• Aug 27th 2009 at 7:55PM
  • 21
Converted plug-in Prius – Click above for high-res image gallery

Cash For Clunkers is officially over and helped put almost 700,000 new cars on the road. Now that the easy $4,500 are no longer available to buyers with low-mpg cars, we thought it'd be a good time to answer AutoblogGreen reader Adam's question that he submitted for our Greenlings series. Adam said he would like to know:
What efforts are being made via research & development that will convert existing vehicles to green vehicles? Is it not important to use the existing fleet vs. constant production of new and more vehicles? I am thinking of classic or special vehicles owners want to keep on the road once alternative engines / fuels are commercially available.
We tackle the question after the jump.

Photos copyright ©2007 Sebastian Blanco / Weblogs, Inc

There are quite a few conversion options available to turn dirty gasoline internal combustion engine (ICE) vehicles. If you have a hybrid, you can get an added battery pack and a plug to make your car a plug-in hybrid (PHEV). If you want to burn natural gas in your car or truck, you can get a CNG conversion. Greasecar kits will allow your diesel car to use straight vegetable oil (SVO). There are even cheap kits to turn your gas engine into one that can burn high concentrations of ethanol (E85 fuel) in a "standard" car. If you're ready to make a huge shift, you can even take out your ICE altogether and put in a bank of batteries to make a pure electric vehicle (EV). Here are some short descriptions of these conversion types and links to get more information:

From ICE to E85
This is the easiest conversion to make. At least, it sure loooks easy. All gas engines in the U.S. are probably already burning a little bit of ethanol (most gasoline is sold with up to 10 percent ethanol in it) and changing a gas engine to burn E85 is technically feasible and there are shops around the U.S. that will install E85 kits into your car. The problem is that the federal government has given its imprimatur to only one commercially-available kit. This kit is sold by Flex Fuels U.S. and works on Dodge Chargers, Dodge Magnums, and the Chrysler 300 2wd and AWD 5.7L Hemi. Cost? $1,295.

From hybrid to PHEV

More expensive than an E85 conversion, turning a gas-electric hybrid into a plug-in vehicle seems to be the leading consumer conversion going these days. The most popular conversion kits come from Hymotion/A123 and Plug-in Conversion Corporation. Depending on the pack that is installed, the converted hybrid will get something like 30 miles of electric-only driving (at speeds below around 35 mph) before the gas engine kicks in. The cost of most of these conversions start at around $10,000, so we had to ask recently: where is the government funding for PHEV conversions?

From diesel to SVO

Another popular conversion is to go veg with an SVO kit. SVO is vegetable oil and is also known as VegOil, waste vegetable oil (WVO) and virgin vegetable oil (VVO). For SVO, you need to start with a diesel car and then find space for a separate tank to store the veggie oil (say good-bye to your spare tire). You'll still burn a bit of diesel fuel with an SVO kit when the car starts up, but once everything is heated up, you can get off the petroleum completely as you drive. SVO conversions start at around $2,000. To learn more about SVO, read this.


Converting a vehicle to burn compressed natural gas or propane has long been the purview of fleet managers across the U.S. Roush offers factory conversions of many big Ford trucks, taking the vehicles directly from Ford and putting in their own propane systems. In Europe, liquified petroleum gas (LPG) conversions are popular and sometimes available with stylish looks. Costs for these conversions vary widely, but start at a few thousand dollars. As with all of these conversions, it makes sense to educate yourself and look out for cheap installers who want to cut corners. For more on natural gas vehicles, read this.


We've covered pure electric conversions in a previous Greenlings. EV conversions often fall into two categories: DIY home conversions done on the cheap and expensive conversions of expensive cars. In the first category, we can point you to previous articles about a teenager who converted his 1988 Mazda pick-up and these shade tree mechanics who lovingly reworked a 1936 Chevy sedan. There are also a lot of ways to learn how to do these conversions yourself. As for the expensive versions – and this would probably interest the classic or special vehicles owners that Adam was asking about – there is no lack of companies who will take your ride and put in batteries and an electric motor. We recommend reading EVAlbum and looking for local conversion shops through the Electric Auto Association to get started. If you don't want to convert your own vehicle, go ahead and order an electric Mustang (for $80,000) or a Shelby Cobra ($125,000). That's pretty expensive, but in the EV conversion game, prices range from $1,000 or so to as much as you want to pay for batteries. You get what you pay for.

  • Image Credit: click for gallery

These are just the most common conversion options out there. Other conversions – for example, to hydrogen power – are possible, but we don't see them too often. If you have a conversion story or a question about a vehicle you'd like to convert, let us know in the comments.

I'm reporting this comment as:

Reported comments and users are reviewed by Autoblog staff 24 hours a day, seven days a week to determine whether they violate Community Guideline. Accounts are penalized for Community Guidelines violations and serious or repeated violations can lead to account termination.

    • 1 Second Ago
      • 6 Years Ago
      LPG is one of the most cost-effective conversions out there. Modern electronic injection kits give you no power penalty to a slight rise in power, with a very modest penalty in economy, which is more than off-set by the fact that LPG is often half the price of gasoline. If you do at least 15,000 - 20,000 miles a year, your ROI is short. The only disadvantage is you have to either give up trunk space or your full-sized spare to fit a tank.

      There's one company in the US selling a modern vapor-injection kit at just under $1000, at http://poweredbypropane.net/ but it's partially DIY. The advantage with this kit is it's self-programming and user-programmable. Most $1000 and up European kits force you to go to the installer to have any tweaks in the fueling maps done.

      I've heard horror stories about older conversions, but as long as the installation is done with an eye towards proper air-fuel calibration, even venturi-type kits (using primitive propane carburetors) can be very reliable. Have a friend who's been running a venturi-equipped Corolla for four years in traffic with no trouble, and the car was already six years old when he installed the kit.


      SVO is another wonderful idea, but new emissions regulations friendly diesels which inject a post-combustion pulse of diesel to clean the particulate filter don't seem compatible with it... causes too much oil dilution as it doesn't vaporize as readily.
      • 6 Years Ago
      A few years back I was thinking of converting an old FWD car into a short range electric-hybrid vehicle. Right now I am going to conduct an experiment with HHO conversion. I know there are some mixed opinions about it, but it does look feasible.
      • 6 Years Ago
      We have just patented a Bio-reactor that produces Hydrogen cost effectively from home, the missing link is a cost effective Conversion Kit. Regards, GAS.
      • 6 Years Ago
      I would say like niky, LPG is the cheapest most convenient conversion for actual cars and older cars from 1908 to today. It cost something like 500$ to 2 000$ for a complete modern computerize installation, no need to remove the gasoline tank, just add the good stuff and enjoy domestic low price fuel. It can be filled too by free hydrogen gas into the same tank, just wait that convenience stores install some small hydrogen producing machines at their outlet or you can buy one for you as soon as it become a popular product. Hydrogen is the only free non polluting fuel their is, on the production of it and in the consumption of it too.

      • 6 Years Ago
      A question. Is it necessary to convert completely to EV? Could one add the motor, controller, etc., to the existing ICE system to create a PHEV? In my case, a 40 mile electric capability would satisfy most of my driving/commuting needs quite nicely while the ICE gets me to those occasional meetings further away. Why should I buy a separate commuter EV to solve this problem when my old car still has better than 100,000 miles on it (according to my mechanic)? I would rather recycle this old car into the 21st century than create more fodder for the waste stream.
        • 6 Years Ago
        If you give up the plug-in part: NetGain's EMIS "utilizes an electric motor configured into the drive train of a conventional [RWD] vehicle", but it seems it only delivers a modest economy gain.

        Several European cars have beefed up the starter motor so the car can shut off at a standstill and get a mild assist pulling away, but again it's a modest economy gain and I know of no conversion kits.
        • 6 Years Ago
        How do you propose the ICE and electric motor work together? Read http://en.wikipedia.org/wiki/Hybrid_vehicle#Hybrid_vehicle_power_train_configurations to get a sense of the engineering involved.

        I guess you could stick batteries and a motor in the back of a FWD car and drive around solely electric, then flip a switch and drive around solely ICE. Somehow one gas pedal has to control either engine.

        40 mile range means a lot of batteries. With the extra batteries, you significantly diminished the efficiency of the car running under ICE. Good luck.
      • 6 Years Ago
      Thanks, Sebastian. We hadn't heard about a few of these plug-in conversions. At CalCars, we're refocusing on just this question, working to promote conversion solutions and companies that can scale to retrofit a substantial portion of the global fleet of combustion vehicles -- especially large gas-guzzlers -- to EV and PHEV, ultimately with the cooperation of automakers. We can already cite a few prototypes and concepts. Two on the road are from Hybrid Electric Vehicle Technologies http;//www.hevt.com for an F-150 pickup truck to PHEV and Rapid Electric Vehicles http://www.rapidelectricvehicles.com for a Ford Escape to EV. We track all this at http://www.calcars.org/ice-conversions.html

      -- Felix Kramer, Founder, The California Cars Initiative
      • 6 Years Ago
      ZENN is planning a great deal of its business around conversion instead of just producing new EVs. If the EESU from EESTOR is all that's it's cracked up to be, this could put conversions within reach for a lot of owners.
      • 6 Years Ago
      If anyone with a diesel is considering fueling with straight vegetable oil (filtered and recycled from cooking oil), he or she should also consider www.plantdrive.com and www.goldenfuelsystems.com and www.fossilfreefuel.com and www.vegpower.com. Greasecar (mentioned in the post) sells good stuff, but these others have been in business a long time as well, have well-engineered, proven systems and are good folks who stand behind their systems. Contact each business a few times to assess responsiveness and customer support experience. Anyone who installs a heated fuel system for veg oil is likely to have lots of questions before, during and after the installation!
      • 6 Years Ago
      The Electric Auto Association has been a resource since 1967 for people wanting to convert cars to EVs. Become a member to receive the monthly newsletter, and find a chapter near you to ask advice of people in your area.
      • 6 Years Ago

      Yup... my kit cost me about $800. Pretty pleased... After a day on the dyno, it makes nearly exactly the same amount of power as my dyno-tuned gasoline maps. Slightly more up to 5000 rpm, and slightly less at redline (I think we're maxing out the injectors... my kit was meant for a standard small four-pot... not a modified car!). Lovely stuff.

      • 6 Years Ago
      Ah, here comes Blencoe conveniently bending the truth as always.

      The bad AVERAGE fuel economy achieved in the study was due to the fact that many of them weren't plugged in regularly, people weren't told how to drive them efficiently and the tests included driving scenarios for which a short-range PHEV isn't well suited.

      The data also shows that those cars that were plugged in as often as possible and driven appropriately saw significant improvements.

      But yeah, I'm sure a Prius converted to run on hydrogen would be sooo much better, right Blencoe? Why waste money on a plug-in conversion, when you could get a car with less trunk space and a laughably small range, for just a bit more money!
      • 6 Years Ago

      Why didn't you mention that 115 plug-in Toyota Priuses with extra batteries that add around $10,000 to the cost did not even achieve 50 miles per gallon in a 2008/2009 Department of Energy study?

      Here is the story covered on AutoblogGreen back on June 15th:


      Greg Blencoe
      Chief Executive Officer
      Hydrogen Discoveries, Inc.
      "Hydrogen Car Revolution" blog
        • 6 Years Ago
        Yeah! Also, Sebastian, you should mention that a hydrogen conversion would probably cost millions of dollars and be limited to a tiny geographical area consisting mostly of Los Angeles.
        • 6 Years Ago
        You hydrogen goons are hilarious!(yes goons)
        You go on boards/forums all day blabbing down electrics by giving and quoting studies which you more than likely funded.
        I see these pro-hydrogen employees on ABG about every other day on a board.


        JUST STOP THE RINGING!!!(lol)

        These guys use search engines and type "conversion to electric" and "EV" and "PHEV" and then copy and paste their lame bashing, like a political slandering commercial.

        Pull you're own plug, AND STFU.
        Thank you.
    • Load More Comments
    Share This Photo X