Energy Resources
Humans are using up the world’s energy resources in a way no other animal has ever done. We use them to provide light and heating in our homes, to plough the land, to cook our food, to travel, to run our factories, and in countless other ways. Whether we are rural workers in a developing country or workers in a wealthy industrial country, we all need energy, although the sources of the energy and the amounts used vary greatly from one society to another.
There are different forms or types of energy. Fuels such as coal, oil (petroleum), and wood contain chemical energy. When these fuels are burnt, the chemical energy changes to heat and light energy.
Electricity is the most important form of energy in the industrialized world, because it can be transported over long distances via cables and transmission lines. It is also a very convenient form of energy, since it can power a wide variety of household appliances and industrial machinery. It is produced by converting the chemical energy from coal, oil, or natural gas in power stations.
Energy resources fall into two broad groups: renewable and nonrenewable. Renewable resources are those which replenish(补充) themselves naturally and will either always be available hydroelectric power(水力发电), solar energy, wind and wave power, tidal energy, and geothermal energy (地热能) or will continue to be available provided supplies are given sufficient time to replenish themselves-peat(泥煤) and firewood. Nonrenewable resources are those of which there are limited supplies and which once used are gone forever. These include coal, oil, natural gas, and uranium (轴).
Coal, oil, and natural gas are called fossil fuels(化石燃料) because they are the fossilized(使成化石) remains of plants and animals that lived hundreds of millions of years age. Burning fossil fuels releases chemicals that cause acid rain, and is gradually increasing the carbon dioxide in the atmosphere, causing global warming.
Energy ResourcesElectricity is the most important form of energy in the industrialized world.