What is Compressed Natural Gas?

There are several different types of renewable and alternative energy that reduce our dependence on fossil fuels. One of these energy sources, only a small step removed from fossil fuels, is compressed natural gas (CNG).

Compressed natural gas is a readily available alternative to gasoline that’s made by compressing natural gas to less than 1% of its volume at standard atmospheric pressure—basically, gasoline is compressed to become more than 100 times smaller in volume than it normally would be. At that point, it is composed of mostly methane and is colorless, odorless, and tasteless.

So what’s so great about compressed natural gas? Chiefly, CNG’s main benefits are being much safer than gasoline, as well as being much better for the environment.

CNG emissions are significantly lower than with regular gasoline. In fact, one study found that, pound for pound, CNG emissions are as much as 26% lower than gasoline emissions, when measuring pollutants like carbon dioxide, unburned hydrocarbons, carbon monoxide, sulfur oxides, and other pollutants.

As far as safety goes, CNG has a narrow flammability range according to the EPA, making it safer than conventional gas. Compressed natural gas is also non-toxic, so it doesn’t pose a threat if it is accidentally spilled. However, it should be noted that CNG fuel tanks are generally heavier than gasoline fuel tanks; this increased mass can cause some safety concerns. These concerns are generally small in comparison to the safety benefits provided by CNG, though.

Compressed natural gas is used in a wide variety of commercial applications, like taxis, trucks, UPS-type delivery vans, postal vehicles, and even in larger and heavy-use vehicles like transit buses and school buses. Using an alternative to gasoline in these high-use machines is a step in the right direction for helping the environment.

There are projects that are making CNG more readily available to the general public as well, if you have a vehicle that can properly run on CNG. Ohio State University plans to build a compressed natural gas station in the Kenny Road area and have it running by next year.

While this type of technology is useful in an attempt to wean ourselves off of fossil fuels while we try to use more renewable energy technology, it does come with some costs. Compressed natural gas requires months to extract and involves a lengthy process to get the gas compressed to its tiny volume. Additionally, to actually get the raw petrol required to create CNG, fracking—a highly controversial and potentially dangerous process—must be used. With these concerns, it is clear that we shouldn’t rely on CNGs as the long-term future of the energy industry—though it is a great piece of stepping-stone technology on the path to 100% renewable energy.