Energy sources natural gas

At midsize scale, a few tens of megawatts, both natural gas and renewable energy technologies offer production possibilities. Megawatt-scale production is especially attractive for biomass-based energy sources. Natural gas production at this scale could provide an efficient response to early market demand for hydrogen, but could not offer sufficient scale economies to compete effectively in mature hydrogen markets. 

For WTW analysis, it is a sufficiently accurate assumption, that natural gas mainly consists of methane (CFI4). Compressed natural gas is also referred to as CNG . Natural gas is extracted, processed, transported and distributed via pipeline to the filling stations, where it is compressed to about 25 MPa. Natural gas sources may vary for different countries. Depending on the source (natural gas quality) and the transport distance (e.g., 4000 km or even 7000 km from Russia, depending on the relevant gas fields) the auxiliary energy needs or energy losses, and hence the GHG-relevant emissions can vary. For the calculation of the energy requirement and GHG emissions for the supply of natural gas, a transport distance of 4000 km is assumed. 

Natural gas (NG) was known in England as early as 1659, but did not replace coal gas as an important source of energy in the world until after World War II. Usefulness of NG has been known for hundreds of years. The Chinese discovered a very long time ago that the energy in natural gas could be harnessed, and used to heat water. In the early days of the natural gas industry, the gas was mainly used to light streetlamps, and the occasional house. 

For fuel cells operating at low (<100°C) and intermediate temperatures (up to 200°C), Fl2 and H2/ C02 (with minimal amounts of CO) are the ideal fuels the F12/C02 gas mixture is produced by steam-reforming/water-gas shift conversion, or partial oxidation/shift conversion of the primary or secondary organic fuels. Flydrogen is a secondary fuel and, like electricity, is an energy carrier. On a large scale, hydrogen is produced from the primary sources—natural gas, coal, or oil. For... 

Table VII.5, Energy Contents of Various Sources of Energy (Synthetic Natural Gas, SNG, and Liquid Natural Gas, LNG, Have About the Same Energy Content...

Fig. 13.1 Global production of energy in 2006 by source. Natural gas plant liquid. T et electricity generation from wood, waste, solar, and wind [1]...

Natural gas is by far the preferred source of hydrogen. It has been cheap, and its use is more energy efficient than that of other hydrocarbons. The reforming process that is used to produce hydrogen from natural gas is highly developed, environmental controls are simple, and the capital investment is lower than that for any other method. Comparisons of the total energy consumption (fuel and synthesis gas), based on advanced technologies, have been discussed elsewhere (102). 

World resources of sulfur have been summarized (110,111). Sources, ie, elemental deposits, natural gas, petroleum, pyrites, and nonferrous sulfides are expected to last only to the end of the twenty-first century at the world consumption rate of 55.6 x 10 t/yr of the 1990s. However, vast additional resources of sulfur, in the form of gypsum, could provide much further extension but would require high energy consumption for processing. 

Renewable carbon resources is a misnomer the earth s carbon is in a perpetual state of flux. Carbon is not consumed such that it is no longer available in any form. Reversible and irreversible chemical reactions occur in such a manner that the carbon cycle makes all forms of carbon, including fossil resources, renewable. It is simply a matter of time that makes one carbon from more renewable than another. If it is presumed that replacement does in fact occur, natural processes eventually will replenish depleted petroleum or natural gas deposits in several million years. Eixed carbon-containing materials that renew themselves often enough to make them continuously available in large quantities are needed to maintain and supplement energy suppHes biomass is a principal source of such carbon. 

With all components in the ideal gas state, the standard enthalpy of the process is exothermic by —165 kJ (—39.4 kcal) per mole of methane formed. Biomass can serve as the original source of hydrogen, which then effectively acts as an energy carrier from the biomass to carbon dioxide, to produce substitute (or synthetic) natural gas (SNG) (see Euels, synthetic). 

Fuel. Natural gas is used as a primary fuel and source of heat energy throughout the iadustrialized countries for a broad range of residential, commercial, and iadustrial appHcations. The methane and other hydrocarbons react readily with oxygen to release heat by forming carbon dioxide and water through a series of kinetic steps that results ia the overall reaction,... 

Fuels ndEfficiency. Natural gas, oil, and electricity are the primary sources of energy propane is used as backup reserve in emergencies. Natural gas is the least expensive and most frequently used fuel, with heat content ranging from 34—45 MJ/nf (900—1200 Btu/ft ) for raw gas and approximately 3 MJ/m (80 Btu/fT) for air-gas mixtures. Fuel oil has heat content between 39—43 MJ/L (139,600—153,000 Btu/U.S. gal). Fuel oil is viscous at low temperature and must be heated before being fed to atomizing burners where it is mixed with air for combustion. 

The use of natural gas as a hydrocarbon source depends on transportation. Over long distances and waterways, Hquefied natural gas (LNG) is dehvered in cryogenic tankers or tmcks (see Gas, natural Pipelines). In the United States, about 22% of the fossil-fuel energy used in 1990 was gas, but in Japan this percentage was much less. 

The main commercial source of methane, ethane, and propane is natural gas, which is found ia many areas of the world ia porous reservoirs they are associated either with cmde oil (associated gas) or ia gas reservoirs ia which no oil is present (nonassociated gas). These gases are basic raw materials for the organic chemical industry as well as sources of energy. The composition of natural gas varies widely but the principal hydrocarbon usually is methane (see Gas, natural). Compositions of typical natural gases are Hsted ia Table 2. 

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