Thursday, 25 October 2012

Methane from Biogas - A renewable source of green energy to be encouraged to generate:

Methane from Biogas - A renewable source of green energy to be encouraged to generate:
Anaerobic digestion of wastes provides biogas. Biogas contains about 60% methane that can be used to generate electricity or used for heat or for fuel for vehicles. Any animal manure, human sewage or food waste will produce methane during anaerobic digestion. Natural gas is methane. Biogas can be "cleaned" to yield purified methane that can be used in the natural gas pipelines.

Methane from biogas is an excellent alternative energy source. Using methane for energy helps the environment by replacing the use of non-renewable fossil fuels with renewable energy. Methane is a green house gas that has 21 times the heating effect as carbon dioxide. Biogas methane is renewable unlike natural gas which is mined from underground wells and is a non-renewable fossil fuel. Methane biogas is about to become much more important as an energy source than it has been in the past, due to the ever rising cost of natural gas.
A. Some facts about methane biogas –
(a) Millions of cubic metres of methane in the form of swamp gas or biogas are produced every year by the decomposition of organic matter, both animal and vegetable.
(b) It is almost identical to the natural gas pumped out of the ground by the oil companies and used by many of us for heating our houses and cooking our meals.
(c) Many countries have for years been steadily building anaerobic digestion facilities for generating electricity from methane produced from manure, sewage and garbage.
(d) Villagers in many undeveloped countries use very simple technology to convert animal and human wastes to biogas for cooking and heating.
(e) Recently hundreds of farms in Mexico and South America have installed anaerobic digesters to collect and use methane from manure to provide energy for farm use. Many of these digesters have been paid for by a company that aggregates and sells carbon credits to factories and utility companies in countries that signed agreements under the Kyoto protocol to reduce greenhouse emissions. Carbon credits are earned by reducing greenhouse gas emissions such as carbon dioxide and methane. These credits have considerable value.
(f) In the U.S., which rejected the Kyoto protocol, most of the methane from wastes is allowed to escape into the atmosphere where it contributes to global warming. However there are about a hundred or so dairy farms, a few pig farms, some landfills and a few municipal sewage treatment plants in the U.S. that are collecting methane from waste and using it for fuel.
B. Unbelievable as it may seem, at this time of approaching energy crisis, most farmers can’t get utility companies to purchase their green, renewable electricity. Possible reasons for this reluctance on the part of electrical utilities range from lack of familiarity with connecting farm generators to pressure from coal and oil companies to maintain monopoly of the utility market. Without the ability to sell the excess power generated
from methane farmers or others with sources of methane can’t afford to install the equipment for collecting methane and generating power as this usually means an investment of a million or more dollars.
C. This kind of situation needs change. Countries where the production of methane from biogas is not practiced, realizing the seriousness of global warming and problems associated with fossil fuel usage, “green energy” generated from sources such as wind, biomass and, in a few cases, bio-methane are to be encouraged by law. Moreover, consumer pressure will likely be needed to motivate more electric utilities to purchase electricity generated from renewable methane thus ensuring energy security.
D. Biogas from manure or other wastes can be purified to yield pipeline grade methane. With the increase in price of natural gas it has become economically feasible in some cases to remove impurities from the methane and sell it to companies supplying natural gas (methane is chemically the same as natural gas). Due to the energy that must be used to clean, compress and transport the gas this is usually not as efficient a route for using methane as feeding it directly into a generator but, unless electric utility companies become willing to pay a fair price for electricity generated from farm methane, selling gas for pipeline use may become a more common practice.

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