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Natural gas, or CNG (Compressed Natural Gas), is an alternative fuel in the united states. But that's incorrect everywhere else. In Thailand, Argentina or Italy, it is a extremely popular fuel, near being mainstream, with hundreds of thousands of drivers using it everyday. CNG is also on the rise in Germany, Switzerland and Malaysia.
Should the United States follow these examples? Before giving a solution, we must weigh the pros and cons of natural gas as a fuel.
The very first advantage is the fact that natural gas is instantly available everywhere in the world, which reserves are plentiful. Everybody's talking about peak oil, but that has heard about peak gas? There's also a strategic issue here, as oil is usually imported from unfriendly countries, whereas natural gas can be pumped in the heartland of America. It's a lesser reason for Europe, because the choice between oil from the Middle-East and natural gas from Russia is not an easy one.
Second, natural gas is cleaner burning than gasoline or diesel. There's much less toxic emissions, and that's why the EPA rates CNG cars so highly. If quality of air is an issue, CNG may be the top choice, and nobody can argue against that. Gas is also much better than regular fuels with regards to greenhouse gases emissions. We are able to provide a few numbers here. A gross estimate would be that whenever a gasoline engine is transformed into gas, with that new fuel, oxides of nitrogen (NOx) emissions are down by around two-thirds, and CO2 emissions are reduced by near to a fifth. They are substantial improvements!
Third, about any gasoline car can be transformed into CNG. All that is required are new injectors, new fuel lines going to a new gas container, and new software for that engine electronics controls. Some professionals advertise that they'll convert almost any car in one single day of work.
Fourth, there is a cost advantage as about nearly all around the world, natural gas is less taxed than gasoline. Filling the tank cost less, and price per mile is down. But the downsides are never far, with the first one being that you have to refill more often. This can be a problematic issue: gas a really low energy density. This is exactly why it's compressed. CNG tanks holds gas in a 200 or 350-bar pressure (5000-psi), but even at 350-bar, a CNG container has to be 3-times as large as a gasoline tank to hold the same energy.
Most often, it isn't the situation. So cars running on natural gas have a shorter range than their gasoline counterparts, along with a much reduced trunk because the CNG container has to be somewhere. It adds weight too, as it must withstand the pressure, meaning it has to constructed from heavy steel. In the future, it's likely that CNG tanks will be created using composite materials, that are very tough but light, however these are extremely expensive.
Handling of gas is also less friendly in the pump. Make sure the bond is leak proof, and also the flow is slower than gasoline. You refill in 5-minutes instead of 3. One other issue comes when you start the car. If you happen to possess a bivalent vehicle, or dual-fuel having the ability to run either on gasoline or CNG, you will observe immediately that power is down with the gaseous fuel. The difference is often as high as 25%!
If your car is slow running on gasoline, do not ever think about having it converted to CNG. Last but not the least problem, alternative fuel stations are few and far between. Unless you live in a large city, there might 't be a station selling natural gas anywhere near to you. You may have gas at your home, but house outlets would be far too small to fill the container of a car. If you don't don't mind 12-hour long refills, that isn't an option.
All of this leads us to the conclusion that CNG might not be the truly amazing solution its partisans would really like us to believe. But there could a method to unite the benefits of gas with those of regular gasoline. It isn't brain surgery, it is something that the oil industry understands how to do, we must convert natural gas into a liquid fuel. That's called GTL (Gas-To-Liquid).
Shell has already been doing it within their huge Pearl project in Qatar. No car needs to be modified, because the new fuel has the same qualities of regular gasoline, and the formerly gaseous fuel could be sold at any normal pump, in every service station in the united states. All of the investment needed is at the refinery. The good points of CNG are retained, it's a greener fuel than usual gasoline, and as easy to handle normally gasoline.
Now, we can see who're those who wants Americans to transform their cars to CNG. They are the people who wants the basic drivers to make investments, but that do not need to make any investment themselves, in producing a fuel drivers could be available immediately.
