About 2000 years ago, the most advanced societies around the Mediterranean Sea and around the Chinese Sea used various forms of non-animal energy for their everyday tasks, including the burning of wood for drying and heating, the burning of organic and inorganic oils for lighting, and the capture of winds for propulsion. It has been estimated that during the largest extension of the Roman Empire, the world population was about 300 million, and the energy utilization about 150 million tons of oil equivalent (toe), that is, about 0.5 toe/yr per capita. this figure did not change significantly until the industrial revolution in a few countries in the nineteenth century. For example, the energy utilization per capita in the United Kingdom anged from about 0.5 toe/yr in 1800 to about 2.8 toe/yr in 1900, to 3.3 toe/yr in 1982.
Worldwide, the population has increased from 300 million at the time of Christ, to 5 billion in 1986, and the energy utilization from 150 million toe 2000 years ago to 7.6 billion toe in 1986, that is, from 0.5 to 1.5 toe/yr per capita. Of course, worldwide averages are misleading because the energy utilization per capita varies by more than a factor of 20 between the most and the least industrialized countries. For example, the 1986 per capita values (in toe/yr) for a few countries are: United States, 7.6; Soviet Union, 5; West Germany, 4.5; Japan, 3.1; Italy, 2.7; Portugal, 1.2; China, 0.65; and Central Africa, 0.3.
(a) Comment briefly on the figures just cited and on how you think the energy utilization of a country may be influenced by demographics (increase in population), geography and climate, type of society (agricultural versus industrial, rural versus urban), technological progress, and economic activity (gross national product).
For your country, answer the following questions.
(b) What fraction of energy consumption is transformed into electricity?
(c) Of the energy consumed, what fraction is coal, oil, natural gas, and nuclear?
(d) What have been the trends in your answers in part (c) over the past few decades?