Types of Natural Gas

What is Compressed Natural Gas?

Compressed natural gas

The most common forms of natural gas are liquid and gas, but what you might not know is that a significant number of commercial vehicles utilize the gaseous form compressed to pressures above 3,100 pounds per square inch.

Compressed natural gas, or CNG, is what you get when gas is placed under pressure but remains clear, odorless and non-corrosive. It can be used in place of gasoline, diesel fuel and propane. Those fuels produce more undesirable gases than CNG, which is considered to be a safer form of natural gas.

Once the gas has been compressed, it is then stored in hard containers for later distribution. These storage tanks, which are designed to last more than 20 years, are typically made up of thick-walled steel, aluminum or composite materials.

Natural gas is considered a valuable resource for fueling vehicles because of the low cost and the fact that it burns cleaner than gasoline or diesel fuel. Natural gas vehicles have experienced an average reduction of 80 percent in ozone-forming emissions in comparison to gasoline vehicles.

CNG is a common source of fuel for commercial vehicles. Taxi cabs, medium-duty trucks, postal vehicles, transit buses and school buses are among the commercial applications for utilizing CNG. Natural gas powers more than 12 million vehicles on the road today.

There has even been limited usage of a home refueling appliance for people with CNG vehicles. In California, the FuelMaker Corporation unveiled such an appliance several years ago, allowing owners of CNG vehicles to refuel their vehicles overnight from their household natural gas line.

With rising gas prices, interest in CNG as an alternative fuel source has surged over the past several years. There are around 12,000 CNG fueling stations in the world right now, and about 500 of them are located in the United States.

How Natural Gas is Formed

Where natural gas is found underground

Natural gas is responsible for approximately 23 percent of all energy produced in the world. It is used to heat the homes of millions of people across the globe, but very few people take the time to understand what natural gas is and where it comes from.

Natural gas is an odorless and colorless substance composed of methane, ethane and propane. Carbon dioxide, hydrogen sulphide and nitrogen are the additional impurities that comprise a smaller percentage of natural gas’ composition.

There are two general types of natural gas. Biogenic gas originates from marshes, bogs and landfills, where methanogenic organisms manufacture the gas. Thermogenic gas is what comes from deep beneath the earth, where buried organic material breaks down under high temperature and pressure.

The natural gas that heats your home comes from deep beneath the earth, under several layers of rocks. The remains of plants and animals from millions of years ago were left buried under layers of rock and soil, before heat and pressure converted that matter into natural gas and petroleum.

To be more specific, natural gas is the result of methanogenic bacteria producing methane while in the process of decomposing organic material, coupled with the decomposition of kerogen. These two actions combine to complete catagenesis, the process that produces both petroleum and natural gas.

Once the gas has been created, it will attempt to migrate to a new location. The layers of the earth are molten rock, and those rocks can act as sponges for natural gas. Certain types of rocks within these layers contain large pores that act as storage units for natural gas.

To access these natural gases, companies drill hundreds of feet into the earth, pumping the gas into pipes. When piped to homes via boilers, furnaces or water heaters, this gas can serve to power ovens, gas-heated clothes dryers, central heating and cooling and more.

What is Shale Gas?


Shale gas is the new topic of discussion in the United States. The findings of composites of this resource have started to strike new and exciting changes in our economy. It has brought about new technologies for drilling as well as provided a lifetime supply of our most valuable resource. Shale gas is sure to generate many conversations well into the future of our society.

Shale is a familiar word that many of us may have come across in our educational background. It is sediment found beneath the earth’s crust. It consists of mud, clay and other organic substances that have been compressed into a rock. While it is not the rock that generates the natural gas it does house it. Within the pores of the shale is where natural gas can be found. This gas is what has come to be referred to as shale gas.

Shale gas is valuable because it an energy source that is expected to drastically reduce greenhouse emissions as its use increases. Just 14 years ago, shale gas was responsible for only 1 percent of the United States natural gas production. By 2010, that number increased to more than 20 percent and the U.S. government’s Energy Information Administration predicts that the United States’ natural gas supply from shale gas will only continue to grow and provide us with cleaner, more efficient energy.

As you can imagine the new type of natural gas has generated a link to our future, our economy, and eco-system. With every new journey there comes learning experiences. Shale gas is not expected to be a replacement for natural gas but rather a shift to a new way of life in which we obtain and utilize the resource.

Is Natural Gas Renewable?

Natural gas burning in rows of blue

Is natural gas renewable? The answer is a little complicated. Natural gas, the fossil fuel, is not a renewable resource. Much of this natural gas we are burning now formed in deposits nearly 300 million years ago. While it may not take another 300 million years to form, scientists theorize that more could form in 50 million years. Since this formation will still not happen within any of our lifetimes, we do not regard natural gas derived from fossil fuels as a renewable resource.

However, there are more ways to obtain variations of natural gas rather than relying on the formation of the fossil fuel. Natural gas is comprised mostly of methane gas, with small traces of ethane, propane, butane and nitrogen. Since natural gas is primarily methane, a substance that is readily available, this can be used to manufacture renewable natural gas, also known as sustainable natural gas.

Methane is manufactured from organic materials in decomposition phases. These materials include substances like livestock manure and vegetation collected from landfills. Renewable natural gas can then be produced economically, and distributed to natural gas suppliers like Walton EMC along the existing gas pipeline system. This makes for efficient method of supplying existing natural gas suppliers with renewable heat and renewable gas energy, at no additional cost to the customer.

Is there a difference between nonrenewable natural gas and renewable natural gas? None that you’ll notice!  Nonrenewable natural gas can be used in the same way as traditional gas to heat water, prepare meals and warm our homes and offices. However, the use of renewable natural gas comes with an added benefit for the environment. When renewable natural gas is converted into energy, methane that would otherwise have entered directly into the atmosphere is ignited which results in the release of a much less damaging greenhouse emission.