Tue, Jan 04, 2005 - Page 8 News List

Letters

Reduce greenhouse gases

Carbon dioxide is considered the major gas that causes the greenhouse effect, or global warming. The combustion of fossil fuels (coal, oil and natural gas) provides energy but emits exhaust containing nitrogen, oxygen, carbon dioxide (CO2), water vapor, sulfur dioxide (SO2), and nitrogen oxides (NOx). CO2 is generated in massive amounts, typically at 2-3 times the amount of coal burned. In terms of CO2, SO2 and NOx emissions, natural gas is the cleanest fuel, followed by oil and coal.

SO2 and NOx are acid rain precursors but their emissions are far less than CO2 emissions and can be reduced by more than 90 percent with currently applied exhaust cleanup technologies. For example, SO2 can be reacted with a lime solution to form gypsum as a byproduct; and NOx can be catalytically reduced with ammonia to form harmless nitrogen and water, with oxygen as a by-product.

In contrast, it is difficult, if not impossible, to reduce CO2 emissions by more than 90 percent unless the fossil fuel consumption can also be slashed by more than 90 percent through a combination of energy conservation, efficiency improvements and lifestyle changes. For example, energy savings can be achieved to a certain extent by preheating combustion air with flue gas waste heat, using oxygen (at an extra cost) or oxygen-enriched air instead of air for combustion, installing fuel cells for electricity generation, etc.

Alternatively, CO2 can be recovered from exhaust, compressed and injected underground or undersea. However, the environmental impacts of CO2 injection have to be assessed carefully since, in essence, CO2 is moved from air to land or water.

There has been an idea to dispose CO2 by catalytically reacting it with hydrogen to produce methane, which is the major component of natural gas. This idea sounds good but has a fallacy: the generation of hydrogen from fossil fuels also involves CO2 emissions. The so-called hydrogen economy has the same fallacy. Even if hydrogen is generated by the electrolysis of water, the generation of electricity from fossil fuels involves CO2 emissions as well. Incidentally, methane in air is another greenhouse gas more potent than CO2 per molecule.

Eventually, when fossil fuels are used up, people will have to use solar energy (including biomass and other regenerable energy) and nuclear energy. The CO2 emission problem might vanish. However, will a "global cooling" or other problems occur instead?

Charles Hong

Columbus, Ohio

Democratize China

One only has to look at the one party government of the People's Republic of China (PRC), including its legislative body, to see how absurd this "anti-secession" is ("Anti-secession bill makes no sense," Dec. 28, 2004, page 8).

Hong Kong's legislative body, however miserable it is, at least has 49 percent of its representatives directly elected by the population. While the "people's" Congress in Beijing, consists exclusively of communists, whose members number around 30 million. In other words, the 1.3 billion Chinese people have no representation -- only the obligation to pay taxes and to die in wars waged by the communists.

As an American, this "taxation without representation," looks to me like a good reason for revolution, be it against colonialists or anything else.

Communist China, from its "Constitution" on, has the same farcical authoritarian laws as previous imperial regimes. They do not recognize the concept of rule of law, or any legal standards outside of China, be it international law or UN declarations. The laws they do have are arbitrarily enforced by layers of bureaucracy, which, in practice, twists these laws to the breaking point.

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