1. Energy, Economy, Population Yu Kuwabara Submitted to Prof. Husar Sustainable Air Qualtiy 02-10-02

2. Energy trends with economy and population  The wealth of resources in the U.S. has provided U.S. the ability to use many types of energy.  With the growing technology, energy sources have changed drastically in the last 50 years.  Although total energy consumption has been increasing, the use of energy per person and per dollar of the GNP have been decreasing in recent years.  Many of the trends have been affected by major events, such as world wars, OPEC, recessions, etc.

3. Overall Energy Consumption  The United States was self-sufficient in energy until the late 1950s when energy consumption started exceeding the domestic energy production.  From 1970 to 2000, U.S. energy consumption grew 45 percent while production rose only 13 percent.

4. Energy use per person  The rate of energy use per person increased from 215 million Btu in 1949 until the oil price shocks of the mid-1970s and early 1980s.  The trend in the 1990s was upward again, reaching 350 million Btu per person in 2000, but not reaching the peak, which was reached in 1978 and 1979.

5. U.S. Population Trend  The U.S. population has been increasing at a steady rate for the last half of the century.  The overall energy consumption has tripled since 1950, while the population has more than doubled.

6. Energy use per dollar  Over the second half of the 20th century, the rate at which energy was consumed per dollar of the economy’s output of goods and services fell dramatically.  By the end of the century, the rate was half of the mid-century level. The rate in 2000 was 44 percent below that in 1970.

7. U.S. GDP Trends  The GDP trends in the U.S. have dramatically increased in the last 50 years.  The rate of increase of the GDP has increased at a much quicker rate than the overall energy use.

8. Energy consumption by end-use  The industrial sector of the economy used the largest share of energy and showed the greatest volatility.  There were two major drops in 1975 and 1980-83 in response to high oil prices.  Transportation was the next largest energy consuming sector, followed by residential use and commercial use.

9. Residential & Commercial  Coal, the leading source of energy prior to 1950 was gradually replaced by other forms of energy.  Natural gas rapidly rose until the early 1970s, and fluctuated around the 1970 level over the next three decades.  The use of electricity steadily rose, as did the losses that came with it.

10. Industrial  Similar to residential and commercial use, Coal gave way to natural gas and petroleum in the late 1950s.  Compared to the residential sector, the industrial consumption had more fluctuations.  The use of electricity grew tenfold over five decades.

11. Summary  With the advancement of technology and the growth of environmental concerns, the sources of energy changed hands numerous times.  Overall, the use of energy per person has been decreasing since its peak in the late 70’s, although it has been increasing in the recent years.  The energy per dollar of the GDP has been decreasing since the last half of the century.