What Is Natural Gas?
Natural gas is a combustible, gaseous mixture of simple hydrocarbon compounds, usually found in deep underground reservoirs formed by porous rock.
Natural gas use is very common and is used extensively in residential, commercial and industrial applications. It is the dominant energy used for home heating with slightly more than one half of American homes using gas. The use of natural gas is also rapidly increasing in electric power generation—replacing the burning of coal.
Natural gas is the cleanest burning fossil fuel, producing primarily carbon dioxide, water vapor and small amounts of nitrogen oxides.
Three segments of the natural gas industry are involved in delivering natural gas from the wellhead to the consumer. Production companies explore, drill and extract natural gas from the ground. Transmission companies operate the pipelines that link the gas fields to major consuming areas. Distribution companies are the local utilities that deliver natural gas to the customer.
Liquefied Natural Gas
What is it?
Liquefied natural gas is natural gas that has been cooled to -260°F (-162°C), which converts it to liquid and makes it easier to transport long distances. When natural gas is converted to liquid, it takes up approximately 1/600 of the space it would as a vapor, making transportation much easier.
LNG is very safe to transport and store. The industry’s safety record is exemplary, and LNG has been transported on oceans and stored in the United States for over 45 years.
Liquefied Natural Gas:
- is an odorless, non-toxic, non-corrosive liquid.
- leaves no residue after it evaporates.
- will not burn until it becomes a vapor, and even then the vapor won’t burn until it mixes with air and becomes extremely diluted (5-15% LNG-to-air). Below 5% there is too little LNG in the air to burn; above 15%, there is too much.
The demand for liquid natural gas is on the rise. The global demand for clean burning natural gas is expected to grow 50% by 2035. Much of this demand will come from Japan, India and China. Natural gas is the cleanest-burning hydrocarbon available, and its transportation to other markets will allow consumers to move away from higher-emission fuels such as coal.
Once converted to a liquid, natural gas is transported to carriers—double-hulled transporter ships that take LNG across the ocean to waiting markets. Because LNG must be cooled to remain a liquid, these carriers are designed to retain the cold (not unlike an insulated cup). LNG carriers can hold up to 9.4 million cubic feet of LNG—enough to fill more than 106 Olympic-size swimming pools.
Energy producers have been transporting LNG this way for more than 45 years. There have been more than 135,000 voyages during that time, all without major incident. Still, the industry takes safety seriously: carriers are double-hulled and cargo tanks are separated from the hull structure.
There has never been a significant LNG cargo release in the 45 years LNG has been transported by sea. That doesn’t mean we don’t take every precaution against the possibility.
If there were a release, vaporizing LNG is not soluble in water and any liquid released on the ocean would quickly evaporate.
LNG is non-toxic and does not enter into any chemical reactions unless it is ignited. The likelihood of LNG igniting is extremely low, and exists only if LNG is first vaporized, then mixed with air in a narrow gas-to-air ratio. Even if it did ignite on the water, it would quickly burn off.
There are LNG facilities around the world, performing a variety of functions. Some export natural gas, others store it for use during peak demand periods, and some produce LNG for fuel or industrial use. There are more than 100 facilities operating in the United States today.
In Oregon, two LNG storage facilities (one in Portland and one in Newport) have been operating safely for decades, helping to provide reliable natural gas service during times of peak demand.
The Federal Energy Regulatory Commission (FERC) is responsible for reviewing the design and operation of LNG facilities, both on-shore and near-shore, under Section 3 of the Natural Gas Act. FERC prepares environmental assessment and impact statements for proposed LNG terminals, and is the only agency that can authorize the construction and operation of an LNG facility connected to an interstate pipeline.