Are You Really Driving On The Cheap?

Honda Civic GX trunk

Reduced trunk of the Honda Civic GX. Anyone for beans on toast with a glass of milk?

Are you really driving on the cheap? That’s the question an owner of a NGV may be asked occasionally. The only monetary disavantage of a NGV is the initial cost which can be alleviated by buying used. In my prior post I listed CNG advantages, many of which are monetary, which is the focus of this article.

As the owner of a Honda Civic GX, for the last two and a half months I have collected data to see how much I am saving and how much you could save.

The CNG savings I have split into two groups, fuel savings and vehicle savings.

Fuel Savings

For a period of 2 1/2 months from 23 November 2009 to 5 February 2010 I noted several metrics. At each refueling I recorded miles driven, gallons used, price per gallon of CNG, and the cost of regular gasoline. I also calculated averages over this time period.

I drove 2,381 miles, needing 18 fill ups, 5 of which were only partial. By this I mean that a NGV is dependent on how well the fuel is compressed. Lower PSI means less fuel in the tank. It isn’t a big deal, it just means you get to drive less before the next fill up.

I refueled on average every 4.1 days, having averaged 132 miles. The most I drove between refueling was 184 miles, the least 91 miles. The range was reduced by the partial fill ups. New 3,600 PSI pumps are being installed which will add 15% more fuel to the tank. My average MPG was 31 which was all city driving.

The cost per gallon was 93 cents, which includes 8 1/2 cents Alternative Fuels Tax, except for one fill up at the University of Utah which was $1/gallon. A Division of Fleet Operations & Surplus Services Gascard is required at the U of U, Utah State, and Jordan, Alpine, and Granite School Districts. The average fill up was 4.32 gallons costing $4.03 (not a typo).

The most I filled my tank was with 5.688 gallons. The rated capacity is 7.2 gallons at 3,000 psi and 8 gallons at 3,600 psi. In theory one could drive 240 miles on a full tank. Don’t ask me what you do if you run out of gas, I don’t like to think about that.

In summary, I spent $72.62 on CNG to drive 2,381 miles while regular gas would have cost $220.89. Regular gas varied from a low of $2.49 to $2.71 a gallon, the average being $2.57. My savings was $128.27, the difference between CNG and gasoline.

Vehicle Savings

There are vehicle savings because of my switch from a 2007 Honda Accord V6, rated at 18 mpg in city driving. By driving the Civic GX the savings amounted to $141.20 over the same time period. This is the difference in the cost of gasoline the V6 would have required.


A coworker and I use Equivalent Miles Per Gallon (EMPG) as a fun measure of the value CNG delivers. EMPG is the mpg you would get if the extra cost of gasoline was converted to mpg using a NGV thus:

Cost of gasoline / Cost of CNG x CNG mpg = Equivalent mpg

Using our formula I came up with an average of 86 EMPG. This will easily exceed over 100 EMPG this summer.


The total savings is $269.47 over 2,381 miles or 11.3 cents a mile. Or put another way: it cost 3 cents a mile. The savings will increase this summer when gasoline rises. CNG prices will likely be fixed at 93 cents even when gasoline crosses $4 a gallon. At least for a time.

The biggest downside is the reduced range and sparse filling stations. A minor inconvenience is the reduced trunk as shown in the photograph. But these are not monetary disadvantages, it just means a few more minutes to stop and refuel.

If you live in Utah it is well worth it for 93 cents gas.

Rickety signature.
Owners of NGVs please comment on your experiences.

Driving On The Cheap

Honda Civic

Take a look at the car in my driveway. It appears to be just a plain 2005 Honda Civic. I purchased it last Friday to help me drive down the cost of transportation. With only V6 engines in my other vehicles I decided to make a change, ready for higher gas prices next summer.

How much cheaper is this Civic for me to drive? Well this is Utah and this Civic is a Natural Gas Vehicle (NGV). With Compressed Natural Gas (CNG) at a subsidized 93 cents GGE throughout the state I really am driving on the cheap.

CNG Advantages

Natural Gas Vehicle

Natural Gas Vehicle

These advantages potentially affect me directly or indirectly economically:

  • Park for free at Salt Lake City parking meters with a Salt Lake City “Green Vehicle” parking permit.
  • Use the Express/HOV Lanes for free while driving alone.
  • Subsidized fuel at less than a dollar GGE.
  • $2,500 tax credit on a first time registration in Utah.
  • CNG is free from adulteration and theft.
  • Less maintenance costs as compared with other fuel-powered vehicles.
  • Fuel system is sealed, preventing any spill or evaporation losses.
  • Increased life of lubricating oils.
  • Mixes easily and evenly in air.
  • Less likely to auto-ignite on hot surfaces.

These advantages affect the community directly or indirectly:

  • Non-toxic and free from benzene.
  • Produces significantly less emissions of pollutants as compared to gasoline.
  • Produced in Utah.
  • Delivered to the service station by pipeline.
I test drove and filled a Cavalier.

I test drove and filled a Cavalier.

CNG Drawbacks

  • Fuel storage needs a greater amount of space.
  • Limited availability of refueling stations.
  • Reduced driving range.
  • Higher vehicle cost.
  • Less choice of vehicles.
  • Converted vehicles have 5% — 10% reduced power.
  • For CNG only vehicles running out of fuel can be very inconvenient.



Me by a CNG pump,

I filled up for the first time last night. It was straight-forward though a little different. The pump was the old style non-digital readout type (not the one pictured). The car gas gauge (interesting that it is still called a gas gauge) was reading 1/4 left. It cost $4.56 to fill and took about the same time as filling a gasoline tank with the same amount of fuel. That is probably enough for about 150 miles. I expect to get 200 miles out of a tank. If there is interest I will post my mileage and CNG use in a future post. I’m used to larger cars but this Civic surprised me with quite some zip. It was a gas to drive.

If you are interested in a used CNG car yourself, check out the CNG Utah website where I purchased my Honda. The folks there were low pressure and friendly. Perhaps you already own a CNG powered vehicle. How do you like it? What have been your savings? Would you purchase another CNG?

By now you may have figured out that my purchase of this CNG Civic was purely economic. As far as the environment is concerned I am against Cap and Trade. The threat from CO2 (plant food) has been greatly overstated. The earth has enough and to spare. Just relax and use the resources God has given you and go out into the world with a little less fear and trembling. You will do just fine in your stewardship despite what Al Gore says.


14 Dec 2011 — There is now a CNG station right in my hometown.
1 Jan 2012 — Without the 50 cent a gallon federal subsidy the price has risen to $1.50/gge in Utah.

Rickety signature.