Natural Gas

Natural Gas Vehicles

A natural gas vehicle or NGV is considered to be an alternative fuel vehicle that uses compressed natural gas (CNG) or liquefied natural gas (LNG) as a potentially cleaner alternative to other fossil fuels. Worldwide, there were around 12.7 million natural gas vehicles by 2010. Combustion of one cubic meter of Natural Gas yields approximately 38 MJ (10.6 kWh). Natural gas has the highest energy/carbon ratio of any widely available fossil fuel, and thus potentially produces less carbon dioxide per unit of energy. Natural gas is predominantly methane, although smaller amounts of ethane, butane, and propone may be present in varying amounts. Natural gas may also be mixed with biogas, produced from landfills or wastewater (or potentially other sources, such as from cows or farmland), which wouldn’t otherwise increase the concentration of carbon in the atmosphere.
NGVs and especially CNG tends to corrode and wear the parts of an engine less rapidly than Gasoline; Thus its quite common to find Natural gas vehicles with relatively high mileage, comparable to diesel engines, at as over 500,000 miles. Emissions are cleaner, there is generally less wasted fuel, and lower emissions of carbon and lower particulate emissions per equivalent distance traveled, potentially making it a considerably cleaner alternative to gasoline engines.

Natural gas powered vehicles are generally considered to be safer than gasoline-powered vehicles for many reasons. Natural gas has a limited range of flammability, meaning it requires the correct mixture of air and fuel to burn, with the required air to fuel ratio being around 5-15%. The ignition temperature required to burn natural gas is also higher, at around 1100 degrees Fahrenheit, which is far more than gasoline at 475 degrees or diesel at 410. As well, natural gas tends to naturally dissipate through the air, being lighter than air, and is much harder to ignite if released into the air. Generally, Natural gas has a relatively strong odor added to it, allowing for the detection of a leak to be significantly easier. As well, natural gas is considered to be non-toxic.

The use of natural gas vehicles faces several limitations however, including fuel storage and infrastructure available for delivery and distribution at potential fueling stations. Natural gas is usually stored under pressure in cylinders, whether it is CNG (compressed) or LNG (liquefied), and as of now these cylinders are generally located in the vehicle's trunk, usually reducing the space available for other uses, particularly during long distance travel. This problem can easily be solved in factory-built CNVs that install the tanks under the body of the vehicle, thanks to a more reasonable positioning of components, leaving more space in the trunk, being a virtual non-issue.
NGV's can potentially be refueled virtually anywhere from existing natural gas lines. This makes home refueling stations that can tap into such lines a possible fuel source.

The U.S. Environmental Protection Agency calculated the potential benefits of CNG versus gasoline based on the inherently cleaner-burning characteristics of natural gas. They found that it could potentially reduce carbon monoxide emissions by 90%-97%, reduce carbon dioxide emissions by 25%,  reduce nitrogen oxide emissions by 35%-60%, potentially reduces non-methane hydrocarbon emissions by by 50%-75, emit fewer toxic and carcinogenic pollutants, emit little or no particulate matter and virtually eliminate evaporative emissions.

Natural gas could easily serve as a cheap, clean, viable source of fuel to power cars, and with simple infrastructure changes or increased adaptability to home natural gas sources, as well as a greater increase to natural gas canisters, could be relatively easy to implement. Natural gas cars may be able to be refilled from a person's home, and natural gas could serve multiple purposes. However, like any hydrocarbon, it's natural sources are limited and it does produce some pollutants; the Moon Titan has over 300 times the Natural Gas as earth, being a potential source for natural gas in the future, meaning that future supplies, in the far future, may not be a concern.