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Some Energy Issues, page 3
Issue 2: Pollution
The burning of substances like wood, coal, oil and gas in general pollute the environment. For most of human history, this has not been a problem. Until recently, only a small number of people were living on the planet and the ecosystem could easily digest the pollution they generated.
However, today the earth’s population exceeds 6 billion and their interactions are much more complex than in the past. The technological revolution multiplied the impact that these numbers have on the environment.
We are looking at scarcity of resources and rising resource prices, greenhouse gases and global climate change, radioactive waste that will remain for millennia and much, much more. The world has become a complex, interconnected system, whose parts influence each other continuously. It is no longer possible to control these systems with the linear approaches of the past but humankind seems to know little other ways.
The pollution through burning fossil fuel for energy originates partly in the resources itself, partly in the process. Burning methane, as a simple example, would theoretically result in the byproducts of carbondioxide (CO2) and water (H20):
CH4 + 2 02-> CO2 + 2 H20.
Carbondioxide is a greenhouse gas and a controlled pollutant. However, fossil fuels don’t come out of the earth as pure substances. They need preparation to increase the energy content and cleanup. Some other substances always remain, like sulfur (S), which are not part of the equation above. They contribute to the pollution, too.
However, an ineffective combustion process also produces carbon monoxide (CO) and other combinations of elements in the air, for example nitrogen, resulting in NO2 and other pollutants.
Some of these issues exist also with alternative energies. For example, if fossil fuel is used to generate the hydrogen for fuel cells, this generation process could produce the same pollutants as a process that burns the fuel. However, fuel cell systems are in general friendlier to the environment than a combustion process and also more efficient.
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