Converting Your Car to Run on Compressed Natural Gas (CNG): Is it Possible and Worth It?

With enough money, time, and experience, it seems that almost anything is possible. In my experience, most engines equipped with spark plugs can run on compressed natural gas (CNG). However, it is essential to note that most engines designed to run on CNG have oil pistons and valve seats that are specialized for this type of gaseous fuel. Therefore, it wouldn't be advisable to undertake this conversion on engines that have not been specifically modified for CNG.

Is it Done Every Day?

Converting a regular gas-burning car to run on CNG is indeed a common practice. It involves installing a CNG line from where you mount your gas container—usually in the trunk—to the engine compartment. You then install the required CNG carburetor and regulator. If you search online or look around, you will notice CNG-powered commercial vehicles like dump trucks and buses. The primary challenge one might face is locating an easy CNG/Propane station to refill your tank, especially if you are in the middle of a large city. However, if you reside in a rural area or near a motorhome maintenance station, you have no trouble refueling.

Professional Modification Shops

For those who aren't mechanically inclined or don't have the necessary tools and experience, it is best to bring your car to a modification shop. These shops have the tools, materials, and expertise to perform the modifications. The process of converting a car to run on CNG requires significant changes to the fuel system, so it is recommended to work with professionals who are certified and experienced in CNG installations.

How to Convert a Regular Gas-Running Car to Compressed Natural Gas (CNG)

To convert a regular gas-burning car to a compressed natural gas (CNG) car, you will need to pay a professional to perform the conversion. There are very few technological barriers to overcome, and converting existing vehicles to burn natural gas is not particularly challenging. However, attempting to do so yourself may result in violations of the Clean Air Act, which could cost you up to $5,000 in fines for every day you drive the converted vehicle.

Is It Worth the Investment?

Nationwide, CNG ranges from 79 cents to $1.50 for a gasoline gallon equivalent (GGE) of fuel. This is a considerable savings over petroleum-based products, especially considering that CNG vehicles achieve the same or better fuel economy per Btu because of the higher octane rating of natural gas. Our test drives indicated no noticeable performance hit, and CNG vehicles can travel a range of about 250 miles. However, there are some extraordinary initial setup costs. A properly installed conversion will run anywhere from $6,500 for a basic system to $12,000 for a high-end installation with a high-capacity composite fuel tank. If you want a home fueling compressor, add another $3,500 minimum. Even at the low end, you are looking at spending enough on the conversion to buy more than 1,800 gallons of gasoline at current prices.

Conclusion

Converting a car to run on CNG can save you a considerable amount on fuel, but the initial costs can be quite high. If you are serious about reducing your carbon footprint and want to save money on fuel, it might be worth considering a professional conversion. Keep in mind that every conversion must be carried out by certified professionals, and this is the legally compliant and safest method to ensure your car is safe and efficient.