I had an email exchange a couple of years ago with my dad and brother regarding CNG (compressed natural gas) vehicles. Here’s what I wrote them.
Did a bit of digging on CNG cars. Found this page on the Consumer Reports website that summarizes things pretty nicely.
I also went digging on Honda’s website. The Honda Civic CNG is currently the only production CNG vehicle available in the US. A comparison with the non-CNG version of the Civic is instructive:
The CNG Civic sells for $25,190 ($4,000 federal tax credit leaves owner with final cost of $21,190)
24/36 MPG, city/highway
8 “gasoline-gallon-equivalent” tank capacity, for 290-mile highway range
The Civic-LX (the trim package most similar to the CNG version) sells for $18,255
26/34 MPG, city/highway
13.2-gallon tank capacity, for 450-mile range
For privately-owned vehicles filling up at retail gas stations, the price difference between gasoline and CNG historically hasn’t been very large. Yahoo says that in 2006 the per-gallon price difference was only 24 cents. Gasoline went a little crazy in 2008 of course, but given that gasoline is back down to 2006 prices, I’d bet we’re back to a 24-cent-per-gallon delta again. You’d have to buy over 12,000 gallons of fuel (and drive 440,000 highway miles) to recover the $2900 difference in purchase price between the two vehicles.
You can can drastically reduce your CNG cost by buying a home CNG filling station that takes CNG from your house at a much lower cost than what you pay at a retail gas station. The two big disadvantages with this are the cost ($5,500 to buy/install the Phill system in your garage), and the fill time (the system has to pump CNG up to 3600 psi to stuff it into your car’s tank, which literally requires overnight-filling). I don’t know how much CNG costs from your house’s line, but even if it were absolutely free, you’d have to drive almost 200,000 miles to recover the cost of the Phill system. That’s on top of the 440,000 miles you already have to drive to recover the vehicle’s price premium.
While there are environmental and foreign-policy advanages that come with CNG vehicles, clearly it currently does not make any economic sense at all for a private vehicle owner to buy a CNG vehicle. Other turnoffs:
- the average joe’s fear of CNG (despite its actual safety advantages over gasoline);
-range anxiety (we can argue about its rationality, but rightly or wrongly, this anxiety does exist for many drivers);
-the CNG tank sits in the trunk, where it substantially reduces cargo capacity; and
-the only production CNG vehicle is the Honda Civic. If buying American cars is important, then CNG (in an out-the-door production vehicle) will not be an option.
-extremely limited availabiltiy of CNG at retail gas stations.
CNG vehicles are popular with fleet owners because the cost of their own private filling system gets distributed over their entire fleet. With cheap CNG available on site, fleet vehicle purchase-price discounts, and a fleet that quickly racks up miles, they can recover a CNG vehicle’s purchase premium in a reasonable time frame.
Aftermarket CNG conversion kits are available for virtually any vehicle (see https://www.cngoutfitters.com/orders/new ), but they’re not cheap either. a conversion kit, including installation, runs about $3000 for a 4 or 6-cylinder engine. Note that this is pretty much the price difference between the CNG and gasoline versions of the Honda Civic, so you’re back to driving astronomical distances to recover that cost. The company at the above link does offer fleet conversion discounts, which again helps to explain the popularity of CNG in fleet vehicles.
In the end, you’ll have to see a very large increase in gasoline prices (or a major shift in consumers’ environmental/foreign-policy sensibilities) before CNG becomes popular with the masses.