Energy consumption, world

World resources of sulfur have been summarized (110,111). Sources, ie, elemental deposits, natural gas, petroleum, pyrites, and nonferrous sulfides are expected to last only to the end of the twenty-first century at the world consumption rate of 55.6 x 10 t/yr of the 1990s. However, vast additional resources of sulfur, in the form of gypsum, could provide much further extension but would require high energy consumption for processing. 

The average daily incident solar radiation, or insolation, that strikes the earth s surface worldwide is about 220 W/m (1675 Btu/ft ). The annual insolation on 0.01% of the earth s surface is approximately equal to all energy consumed (ca 1992) by humans in one year, ie, 321 x 10 J (305 X 10 Btu). In the United States, the world s largest energy consumer, annual energy consumption is equivalent (1992) to the insolation on about 0.1 to 0.2% of U.S. total surface. 

The demand for energy is continually increasing and the highest energy consumption in the world occurs in the United States. In 1989 consumption totaled 8.6 x 10 MJ (81.3 x 10 Btu) or 11.7 metric tons of coal-equivalent per capita (85). World recoverable reserves were about 120 times the annual coal production in 1988 and about 10 times that for the additional reserves beheved to be in place (1). Estimated coal consumption reduces the known recoverable reserves at about 1%/yr. Whereas the use of bituminous coal is expected to continue to increase in terms of tonnage, the percentage of coal used in the United States has stabilized as shown in Table 11. 

Besides operational energy use, corporate decisions have an impact throughout society. One reason that per capita energy consumption in North America is much higher than in the rest of the world was the decision of corporate leaders to expand and relocate away from city centers and to major beltway loops in the suburbs. This necessitated more trucking and a workforce reliant on the private automobile instead of mass transit. In an era of tremendous job insecurity, even the most energy-conserving person... 

The U.S. Department of Energy has estimated that the total usable geothermal energy resource in Earth s crust to a depth of 10 kilometers is about 100 million exajoules, which is 300,000 times the world s annual energy consumption. Unfortunately, only a tiny fraction of this energy is extractable at a price that is competitive in today s energy market. 

From the onset of the Depression (1929) to the beginning of World War II (1941), petroleum s share of total U.S. energy consumption continued to expand, from 24 percent to more than 34 percent (while natural gas increased its share from 8 to 11 percent). Coal continued to lose share in the nation s energy output, from 62 percent to 54 percent. Over the same period, output of motor fuel, while not matching the growth of the previous decade, nevertheless continued its upward trend, from 256.7 million barrels to 291.5 million barrels. 

Over 80 percent of the world s energy consumption comes from nonrenewable sources that cannot be sustained indefinitely under current practices. If technological advances continue to make conventional energy resources plentiful and affordable for many years to come, the transition to more sustainable energy sources can be smooth and minimally disruptive. 

From various U.S. DOE sources, projections have been made that the worldwide annual energy consumption in 2020 could be 75 percent higher than it was in 1995. The combined use of fossil fuels is projected to grow faster from 1995 to 2020 than it did from 1970 to 1995. Natural gas is expected to account for 30 percent of world electricity by 2020, compared to 16 percent in 1996. 

The energy consumption of the world is about 40 X 1015 kj/y and does not change with time. 

Sulfur dioxide Is formed primarily from the Industrial and domestic combustion of fossil fuels. On a global scale, man-made emissions of SOj are currently estimated to be 160-180 million tons per year. These emissions slightly exceed natural emissions, largely from volcanic sources. The northern hemisphere accounts for approximately 90% of the man-made emissions (13-14). Over the past few decades global SOj emissions have risen by approximately 4%/year corresponding to the Increase In world energy consumption. 

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