How Electricity is Generated


Coal is an inexpensive fuel and there is a lot of it but coal plants now require expensive air-pollution controls to capture mercury and sulfur dioxide. These plants are significant contributors to acid rain and they spread enormous quantities of fly ash across wide areas. Furthermore, the coal is not cheap in terms of human misery: hundreds of miners die each year. Coal requires an extensive transportation system to get the coal to plants.

Nuclear energy is the most concentrated energy source available and the fuel is inexpensive and easy to transport. Furthermore nuclear plants have no environmental impact like coal emissions. However, nuclear plants require a large capital up-front cost because of the containment and storage systems. While the waste is very compact and stable it has become a political football because it requires either recycling or long-term storage. Furthermore, despite more than half a century of operation around the world with only three accidents nuclear plants are still perceived by some sections of the public as dangerous.

Hydropower is clean and very inexpensive once the dam has been built. However, there are now limited locations were new dams could be built without displacing large populations and causing environmental damage to the land taken over. Unfortunately too dams are not safe and collapse regularly around the world resulting in thousands of deaths downstream.

Gas and oil are easy to obtain once the sites have been found but they are limited resources in the long term. There are large swings in cost with supply and demand and they are both better used for other energy uses (transport and space heating) than in generating electricity. Furthermore, oil has caused several wars over its control the last still in progress after five years.

Wind has limited application although it is free once the infrastructure has been constructed. Large amounts of land are required for a wind farm and yet the amount of energy produced is a small contributor to an industrialized nation. The equipment is expensive to main especially that located offshore in salt water. It is highly dependent upon moderate climate (not available in mid summer or in windstorms.) As noted the use of wind is very damaging to the environment and to bird populations.

Solar power is very diffuse and it requires expensive equipment and extensive dedicated land to accumulate enough to make electricity. A facility requires an immense amount of material for mirrors etc. although a solar plant could be built in stages so that capital investment is spread out over years. Solar energy is excellent for use in powering remote roadside signs and in providing a little add-on heat to homes and swimming pools but like wind it is insignificant in an industrialized nation.

Biomass and refuse incinerators have very low efficiency and output although small facilities can be built for small applications. The fly ash waste contains metals such as lead and cadmium, which require expensive separation equipment and controls. However, biomass electricity is a useful byproduct when it is necessary to burn agricultural wastes.

Fusion has the promise of producing large amounts of energy from the use of tritium and hydrogen in seawater. However it is not yet feasible even after 60 years of expensive research. No power has been produced by any of the experimental facilities. If such a facility were to be built half a century from now although it would have low levels of radiation in operation like present nuclear plants it generates very large quantities of radioactive metals as waste. These would require disposal.