Can I run a car on natural gas?
Can you run a car on compressed natural gas? Yes, you can. Wow, that was easy. I guess we can wrap up this week's Greenlings post quickly. Not so fast. Like just about everything else in this world, the full answer is much more complicated than the simple yes. Here in the United States, there are but a handful of vehicles available that are equipped from the factory to run on CNG, and there are even fewer places to get those vehicle's gas tanks topped off with the stuff. Have a car that you want to convert? That's great, but a number of major modifications are required to run a vehicle on natural gas if it was originally intended to burn gasoline.
For these reasons and a few more, just one tenth of one percent of all natural gas consumed in the United States is currently used for transportation. Most of it is used to generate electricity and to heat people's homes and food. That's a shame, as liquefied and compressed natural gas hold significant promise as a viable alternative to other fossil fuels in the transportation sector. How so? Click past the break to keep reading this week's Greenlings.Why use compressed natural gas in the first place, and why use it for cars?
For one, CNG is cheaper than gasoline or diesel. Lots cheaper, in fact – in some cases about a third of the price of an equivalent amount of gasoline. In addition, natural gas burns significantly cleaner than other fossil fuels.
The United States EPA lists the following statistics about vehicles running on natural gas:
- Reduce carbon monoxide emissions 90%-97%
- Reduce carbon dioxide emissions 25%
- Reduce nitrogen oxide emissions 35%-60%
- Potentially reduce non-methane hydrocarbon emissions 50%-75%
- Emit fewer toxic and carcinogenic pollutants
- Emit little or no particulate matter
- Eliminate evaporative emissions
Gallery: 2007 Honda Civic GX
What vehicles are currently available that use natural gas?
Here in the U.S., the list is tiny. There's the Honda Civic GX and the... um, well that's it from the major manufacturers, at least on the consumer level, and the GX is only available in California and New York. At least it's a solid choice. The United States EPA rates the Civic GX as the cleanest car available in America.
Further, the automotive CNG industry was dealt a serious blow earlier this month when Fuelmaker, a producer of natural gas refueling systems, was forced into involuntary bankruptcy by parent company Honda.
Many automakers currently produce vehicles equipped to run on CNG for fleet or government use. All told, there are currently 120,000 natural gas vehicles on the road in America, which is a tiny number in comparison to the millions of gas and diesel vehicles. According to Wikipedia, there were over 7 million natural gas vehicles on the roads worldwide in 2008, mostly in Europe, Asia and South America.
Gallery: Volkswagen Scirocco GT24-CNG
Are there any drawbacks to using natural gas in a vehicle?
Of course there are. Besides the fact that there's only one actual production CNG vehicle in America, there are other reasons why consumers don't often consider CNG a viable option. One big drawback is that it's more difficult to refill the fuel tank of a car that runs on natural gas. Another problem is that the storage tanks required for natural gas are big and bulky, so there's a give-and-take relationship between how much fuel is carried and how far you can travel.
Finally, there aren't all that many places to refuel a natural gas vehicle. The U.S. Department of Energy operates a website with natural gas filling stations that you can find here. Check the box for compressed natural gas, enter your zip code and have at it.
What does the future hold for natural gas vehicles?
One of the most well-known proponents of natural gas for transportation is T. Boone Pickens, a man who made most of his fortune on oil. Now, Pickens is pushing forward with a plan to divert the natural gas that's currently used to generate electricity to our transportation sector. Of course, that would offer little help without a corresponding increase in the number of vehicles that run on natural gas. There have been concept CNG vehicles like the CNG Camry Hybrid and Mercedes-Benz B-Class, but so far no more automakers have announced plans to offer natural gas vehicles in the U.S.
Gallery: Toyota Camry CNG Hybrid Concept
If you don't want to wait for more major manufacturers to begin producing natural gas vehicles, there are a number of companies out there that will convert your car to run on natural gas. The U.S. Department of Energy keeps a list of companies that offer conversions, click here to check it out.
Reader Comments (Page 1 of 2)
travis 12:46PM (4/23/2009)
87% maybe produced locally, but the other 12-13% is produced in mexico and canada and piped in just over the border.... Very little is actually put on vessels and shipped in, although we may be getting a small amount from offshore.
CNG is great, the tanks are safe if built well, even if they aren't, and they explode, things disperse very quickly. They're actually safer than gas tanks. I've seen movies of a full tank of CNG sitting on a pile of burning pallets and it did nothing. One was fixexd to the front of a car and dropped .... nothing.
The biggest PROBLEM in the US is that the EPA is regulating conversions. In order to certify it, the emissions of the conversion must be guaranteed. Right now, mostly ford and chevy trucks are certified, as well as the Honda GX and a couple other small cars. There are kits available, but they have not been tested to comply with emissions. Their big concern is NOx emissions. If we can get more kits certified on some of the most popular cars here in the US, we could move forward. The conversion kits and tank aren't outrageous.... but finding a way to fill your tank might prove problematic.... since fuelmaker just bit it.
Just think, CNG and electric hybrid... locally produced fuels. It may not be the cleanest solution, but its a step in the right direction and will help the US with dependance on foreign oil.
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Lad 12:52PM (4/23/2009)
Natural gas has a definite place in fueling automobiles...indirectly using the grid. I think we should not build additional coal plants; instead expand the current coal plants to produce more electricity using natural gas; then once the gas is on site, close down the coal part and switch the whole plant over to natural gas. Then as solar, wind and other forms of power plants come on-line, shut down the natural gas plant. Remember, once you build a new coal plant, you may have it around for 20 to 50 years. Natural gas is far less an atmospheric polluting source than coal. Yes, it is more expensive to go this way; however, if you think this is expensive, wait until you try to pipe and sequester the CO2 underground and cork it!
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Ronnie Oldham 3:02PM (4/23/2009)
Much more inefficient to use the natural gas to produce electricity for cars. Why not cut the middle man and run it directly in the car? I do. My CNG Ford Focus' emissions are so low that I often joke that my car actually acts as an air filter for my community.
Frankly, CNG is an exceptional motor fuel and Jeremy is wrong saying that it is more difficult to refuel. You just pull up to a dispenser, connect the hose and swipe your card. He is right about the additional space requirement and limited refueling infrastructure though, but that is about to change. Also, the modifications required for a conversion are not that "major." Most of the conversion is around the new tank and fuel lines. The engine remain basically unchanged. Many converted vehicles are configured to use either CNG or gasoline.
There are more and more EPA certified systems all the time. I currently offer Focus, Fusion, Impala and light truck conversions. With the available incentives and tax credits, it make a lot of financial sense for many to make the switch to CNG. More importantly, we have an ample supply here in the US.
Ronnie Oldham
Austin, Texas
Kagato 12:51PM (4/23/2009)
I think this is a great concept! I hope that there are vacuum hoses built into all of the seats. Sometimes the passengers produce more 'natural gas' than the driver.
:)
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Carney 1:01PM (4/23/2009)
Natural gas is inconvenient as a vehicle fuel because it is a gas and not a liquid at normal temperature and pressure. Also, it is not "backward compatible" with gasoline - an NG vehicle low on fuel had better be near an ultra-rare NG fuel station because it can't use any of the over 200,000 gasoline stations out there.
However, NG can easily and cheaply be made into methanol.
And methanol IS a liquid at normal temperatures and pressures, and a fully flex-fueled vehicle CAN use methanol as well as gasoline.
So NG can play an important role in weaning us from oil, but only if used as part of a smart strategy to move us to an alcohol-based system.
NG by itself is a distraction and ultimately a dead end.
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Funz 3:17AM (4/24/2009)
Not true, here in northern Italy dual-fuel gasoline / methane cars are booming, as CNG refuelling stations begin to be enough diffuse and government is funding CNG and liquefied gas cars buyers.
There is actually no practical problem in driving a CNG car, except for a slight reduction on power.
Carney 12:08PM (4/24/2009)
I didn't know there were cars that can run on either gasoline or natural gas, funz. Can you post some links?
Even if this is the case, it seems to me you'd have to use separate fuel tanks, since IIRC CNG needs heavy, reinforced, high-pressure containers shaped like spheres or domed cylinders. That adds weight, decreases passenger and cargo space, and increases mechanical complexity which reduces reliability. It also reduces the amount you can fuel up in either fuel.
It makes a LOT more sense to have ONE bigger fuel tank than two smaller ones. You can fill the WHOLE thing up with either gasoline or alcohol, whatever's available. And because alcohol is a liquid the tank can conveniently assume any irregular shape dictated by the car's contours and the space between the inner and outer surfaces.
If we use NG as a vehicle fuel the only logical choice is as methanol.
guyledouche 9:34AM (7/13/2009)
Carney,
your infinite wisdom regarding this fuel source is impressive to say the least. I am in awe while reading your prolific statements and cannot get over the amazing level of profficiency you have with this topic.
In other words, SHUT THE F*CK UP!!!
You are utterly clueless. CNG is an excellent fuel source for vehicles, and much like using you electricity at home to refuel your EV, a large percentage of Americans have NG piped right into their homes and can simply refuel their CNG car in their garage. Also, unlike EV's which will probably just be charged at home or at work for the foreseeable future, CNG refueling stations are popping up all over the world and many more are planned.
Google and Autobloggreen are amazing tools for research, please do us all a favor and use them before posting you nonsense beliefs and theories on this site.
brandon 1:11PM (4/23/2009)
my question is about volume. In a car converted to run on CNG how much of a loss of range do I get with the same size tank? I drive 100 miles per day and if I can't have a least a 400mi range I wouldn't even consider it.
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Carney 1:57PM (4/23/2009)
It's a bit hard to compare.
You'll see that CNG is sold in GGE's to help that comparison. Since it's a gas not only volume but PSI counts.
See this page:
http://en.wikipedia.org/wiki/Gasoline-equivalent_gallon
"One GGE of natural gas is 126.67 cubic feet. This volume of natural gas has the same energy content as one US gallon of gasoline (based on lower heating values: 900 BTU/CF of natural gas and 115,000 BTU/gallon of gasoline).[11]
One GGE of CNG pressurized at 2,400 psi is 0.77 cubic feet. This volume of CNG at 2,400 psi has the same energy content as one US gallon of gasoline (based on lower heating values: 148,144 BTU/CF of CNG and 115,000 BTU/gallon of gasoline.[11] Using Boyle's Law, the equivalent GGE at 3,600 psi is 0.51 cubic feet which corresponds to 14.5 liters or 3.82 actual US gallons.
The National Conference of Weights & Measurements (NCWM) has developed a standard unit of measurement for compressed natural gas, defined in the NIST Handbook 44 Appendix D as follows: "1 Gasoline [US] gallon equivalent (GGE) means 2.567 kg (5.660 lb) of natural gas."[12]
When consumers refuel their CNG vehicles in the USA, the CNG is usually measured and sold in GGE units. This is fairly helpful as a comparison to gallons of gasoline."
brandon 2:26PM (4/23/2009)
So in other words with a 3600psi tank that is physically the size of my 15 gallon gas tank I only get 3.93 GGE of CNG dropping my 400 mile range down to 105 miles? Doesn't sound very ideal to me. Plus a 3600psi tank would likely have to be cylindrical which really limits the ability of designers to efficiently use space.
Is there any way to make diesel out of NG? I personally would rather get a 700mile range from my 15gal tank than 105miles.
Ronnie Oldham 3:01PM (4/23/2009)
The short answer is that an equivalent number of gallons (GGEs) of CNG required 4.7 times the space. You can either give up range and sacrifice some trunk space etc. for additional fuel storage.
Carney 4:53PM (4/23/2009)
I don't know. I doubt it is worthwhile. See my post above. NG can be made into methanol, a far cleaner liquid fuel than diesel, and one which is gasoline compatible in flex-fuel vehicles.
Carney 12:12PM (4/24/2009)
I don't know. But why would you want to make diesel out of NG?
Diesel is also incompatible with gasoline, ruling out long or spontaneous trips.
But methanol, which CAN be made from NG, IS compatible with gasoline in a fully flex-fueled vehicle.
And alcohol fuels burn much more cleanly than NG, gasoline, and certainly diesel.
John Rowell 4:15PM (4/23/2009)
Honda's CNG Civic has been available to California residents for quite some time, but it never really caught on. I think CNG just doesn't carry the psychological impact that electricity or hydrogen does.
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jharlan 4:28PM (4/23/2009)
CNG or LNG are viable solutions because we have the reserves and the technology, it is cleaner and cheaper, but apparently our lobbyists don't have the will.
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nardvark 7:58AM (4/24/2009)
One thing that is not mentioned is that methane is an incredibly effective greenhouse gas. The cross section for IR absorption of a methane molecule is about 40X that of a CO2 molecule. So if you're doing this for global warming reasons, you better make sure you aren't leaking ANY methane into the air. Even a trace amount will become a significant source of heat trapping.
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Chad 10:20AM (4/24/2009)
I think most people get it wrong when they look at replacements for unleaded gasoline. It is not a zero sum game, I don't have to drive a dedicated single fuel vehicle. My Nissan X Terra can hold 20+ gallons of unleaded, however the I only have to give 50% of cargo area to put the 10 GGE CNG tank in (assuming 3200 psi fill).
I can drive everywhere in the US and still get gas. The car is a dual fuel. The real clincher is that I can drive locally on entirely CNG. When you consider that over 90% of my driving is local that really begins to add up. I also travel a fair amount for work and have had no problem finding relatively convenient CNG filling stations in most of the western states (except for Idaho).
At the end of the day I think that creating cars that can run on multiple fuel sources is the real answer:
Methane + Diesel
Diesel + CNG
Unleaded + Electricity + CNG
CNG + Unleaded
Chad
www.ngvdriver.com
*you cna buy a new CNG GX in almost every state, not just CA and NY
**there a lot more in home fueling solutions just FuelMaker, it concerns me that the Fuelmaker bankruptcy is getting so much press as a death-nail to CNG. A simple google search will turn up others.
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Carney 10:11AM (4/28/2009)
What about the points I made above?
Alcohol makes more sense as an alternative fuel.
No need for bulky heavy high-pressure gas canisters that eat up passenger or cargo space.
Instead, you'd have ONE large fuel tank that can be any irregular shape, filled with gasoline, methanol, ethanol, or any other alcohol, in any mix or none at all. No settings to set, no switches to throw, all seamless and automatic and user-free.
And you can make methanol from natural gas cheaply, so NG plays a role, but merely as a feedstock for a much more convenient and practical alternative fuel.
Chad 12:17PM (4/28/2009)
You and I are singing the same song on creating substitutes. The array needs to be broad and deep. If the community gets to dependent on one or another fuel source (be it methanol or CNG or Electricity) then we step into the same problem that we are in right now.
When I lived in Brazil cane based ethanol made sense, it was temperate all year round. Furthermore cane grew like a weed. I think it would be much harder to implement an electric grid system in all but the major cities in Brazil - the infrastructure could not support it. However, in UT Ethanol or Methanol would only work for 8 months out of the year as it is too cold the rest of the year the fuel begins to gel and loses functionality (I don't know enough about the energy cost process to convert Methane to Methanol to talk to that point intelligently) but, Utah could support an electric grid...
The solution is varied and wide, the more people evangelize any one solution as THE SOLUTION, we will continue to run into problems. From where I sit groups like the EPA and certain Gov. entities that restrict laws around innovation and exploration of viable substitutes are the real problem. How is any alternative fuel source going to gain traction if every innovation is deemed illegal and not road worthy.
One of the first innovations needs to be in creating a certification process for a wide array of small and local groups to begin making street-legal conversions of many different types of fuels. Then incentivizing the early adopters (read: early consumers) of these conversions so that the capitalistic process of innovation, competition, and adoption can begin to take place.