The U.S. enjoys one of the largest reserves of natural gas in the world. The Potential Gas Committee (PGC) and U.S. Department of Energy (DOE) estimates forecast the U.S. has a future supply of more than 100 years. However, there are alternatives to traditional production that can supplement supplies today and provide natural gas far into the future.
Methane is the natural byproduct of decomposing organic waste. Technology has been developed to accelerate the natural decomposition of a variety of waste products—including animal waste, crop waste, and even sewage. The result is biogas, which can then be refined and cleaned of any impurities to become biomethane, a fuel clean enough to be injected into
the pipeline system or used as a vehicle fuel. Successful projects have been developed at landfills, dairies and other locations that process a high volume of organic waste. Because there will always be sources of organic waste, biomethane is a renewable fuel that will continue to be a reliable source of natural gas. Visit the Biomethane Page to learn more about this renewable resource.
Methane hydrates are crystalline solids consisting of methane molecules surrounded by a cage of water molecules. They are stable in Arctic areas and in ocean floor sediments at water depths greater than 1,000 feet. Methane hydrates are found throughout the world—including off all U.S. coasts. While good data on methane hydrates is limited, the U.S. Geological Survey conservatively estimates that energy contained in the world’s methane hydrates is twice the energy contained in all known fossil fuels—twice of all the natural
gas, petroleum, and coal combined.
In 2008, the U.S. Geological Survey developed its first-ever resource estimate of technically recoverable natural gas hydrates. The federal agency estimated that there are 85.4 trillion cubic feet of undiscovered technically recoverable gas from natural gas hydrates on the Alaskan North Slope, thought to be the largest known resources of natural gas in the world. Another project was recently completed that developed technology and collected data to characterize the methane hydrates in the deep water of the Gulf of Mexico.
The focus of the study was safety and seafloor stability, as well as to assess the feasibility of methane hydrates as a future source of energy. Although more work is needed to determine how methane might be produced from methane hydrates safely, economically, and responsibly, hydrates hold great promise as a future source natural gas.
The U.S. is estimated to have about 481 billion tons of coal reserves, more than half of which can be recovered under present technical and economic conditions. While technology has minimized most of the air pollution issues associated with coal, coal combustion still produces substantial amounts of carbon dioxide (CO2), which is a major greenhouse gas.
Currently, there is much publicly and privately funded research into CO2 sequestration, i.e., injection of gaseous CO2 into old gas wells and other underground storage where it is supposed to remain secure for tens of thousands of years. However, another method of CO2 sequestration is to gasify the coal through a pyrolysis process. The gas can then be converted into a natural gas substitute, and transported through the country’s 1.5 million mile gas line system. Importantly, the excess carbon is converted into a solid (charcoal), not a gas. The solid can then be easily buried, without concern that, at a future time, it will escape into the atmosphere.