Several readers have written to ask about compressed natural gas (CNG) conversion kits. Converting a conventional gasoline car to CNG is complex, but not necessarily difficult, and quite do-able. And if you are mechanically inclined, it could feasibly be done in your own garage. The other option is to find a willing mechanic that will install a CNG kit for you. One potential hoop to jump through could be emissions certification for your particular state—some states require special conditions since you'd be changing the vehicles "engineered" fuel type. They all differ, and some are easier to work with than others. The U.S. Department of Energy offers this emissions certification information and CSA America offers a searchable database of compressed natural gas cylinder inspectors.
Another be-aware-before-you-do-it-item is to locate the CNG fueling stations in your area to be sure you’ll have regular access to the fuel. This CNG and alt fuel station finder includes pricing for the United States. Another alternative, if you have natural gas in your home, is to install a Phill home refueling appliance. These devices compress and dispense a tank of fuel in about 8 hours. They are designed to be attached overnight, delivering a full tank by morning. Another option could be to install a CNG compressor at your house—this company offers one for $4,500.
Following are the companies (listed alphabetically) that we have found to-date that sell compressed natural gas (CNG) conversion kits (and one sells already-converted vehicles). Please drop us a line if you find others and we’ll add them to the list:
AllThingsCNG.com - This company offers bi-fuel CNG/gasoline conversion kits and CNG cylinders. Kits are to be installed by a qualified trained professional, and you can contact them with inquiries and/or order directly online. Prices for kits range from $995 to $1895 and cylinders range from $1395 to $3995.
CNG Outfitters – This company offers natural gas conversion and dual fuel conversions (the vehicle can run on both gasoline or natural gas) for on-road and off-road applications. They offer kit and tank ordering directly from their website, with prices starting at $1450 and $2200 respectively. For folks in the Utah area, they offer professional installation in 10 hours, with the basic install costing $1500.
Devendra Automobiles Pvt. Ltd. – This company, based in India, offers CNG and LPG kits and a variety of two- and three-wheeled modes of transportation. Inquire directly to the company for more information about pricing and products.
Energy and Water Solutions (EWS) – This company offers bi-fuel CNG/gasoline conversion kits and cylinders. Orders are accepted online or by phone, and prices start at $999 for electronic fuel injected and carbureted gasoline engines—and it looks like they’ll be offering 8- and 10-cylinder diesel conversion kits soon too. Composite cylinder storage tanks are purchased separately, prices range from $1199 for the 5.2-gallon to $1499 for the largest 7.4-gallon, with a variety of other options.
FuelTek Conversion Corp. – This company offers alternative fuel conversions for a variety of American vehicle makes and models—installations are available directly at their facility for those in the Denver Metro area. Choose from compressed natural gas (CNG), propane (LPG) or bi-fuel (operates on gasoline or CNG/LPG with the flip of a switch). They also offer replacement parts and ready-to-go conversion kits for the Ford F-250—sold only to qualified conversion shops.
Ganga Engineering System – Located in New Delhi, this company says they are a “Government approved LPG & CNG Fitment Centre,” capable of installing CNG conversion kits on buses, cars and other vehicles. They also sell CNG and LPG kits and related spare parts. Pricing is available on their website, along with a form to contact them directly with questions.
Morris Auto Sales – While not a company that offers direct conversion kits of conversions, they are located in Oklahoma and will ship their already-CNG-converted vehicles anywhere in the country.