Susan S. Van Biersel
For hundreds of years, man has found ways to harness energy, such as using animals to do work or designing machines of varying sophistication to tap the power of wind or water. The advent of the Industrial Revolution in the late 1800s, however, was accompanied by the widespread and growing use of fossil fuels such as coal, oil, and natural gas. It was at this point in time in America that the total work output of engines surpassed that of work animals1. As the United States industrialized, coal began to replace wood as a primary fuel. As industrialization proceeded, petroleum and natural gas replaced coal for many applications. The United States has since relied heavily on these three fossil fuelscoal, petroleum, and natural gas for the majority of their energy needs.
Until the 1950s, the United States was nearly energy self-sufficient. However, during the 1960s, energy consumption began to outpace production, largely due to the increased use of the automobile. For the following three decades, the gap between domestic energy production and consumption has continued to grow. This has resulted in America’s dependence on other countries for some of its energy needs, in particular, petroleum. Since the mid 1980s, the United States has imported nearly half of its petroleum needs. Some of it has come from countries other than those in the Middle East, such as Mexico, Venezuela, and Nigeria. In 1994, U.S. oil imports broke through the halfway mark at 50.4 percent, the first time that our foreign-oil consumption exceeded that of our domestic production. All of this, of course, has had serious international implications. As quoted by Harvey Blatt, in one of his recent college textbooks, “Any industrial nation with a petroleum-based economy that imports half its oil is on shaky ground regarding oil price and stability of supply”2
Historical Perspective
We will open the unit by touching briefly on the political implications of energy policy. Particularly given the current situation in the Middle East, an entire unit could certainly be written on that issue. However, an effort will be made at the onset of the unit, and throughout, to give the students somewhat of an historical perspective on U.S. energy policies, what broad-range effects they can have, and how they do, indeed, affect their everyday lives (look at today’s gas prices). Students will compare and contrast the energy policies of the last four Presidential administrations, beginning with Ronald Reagan (1980-1988). The platform of the Reagan administration was to downplay the importance of government responsibility for dealing with the energy problem. The ensuing Republican administration of President George H.W. Bush (1988-1992) continued the Reagan policies of minimizing government regulation of the energy industry. The following Democratic administration of President Bill Clinton (1992-2000) returned government involvement to energy and environmental issues. Several major energy bills were proposed by this administration, but were defeated by the Republican Congress in power. Nevertheless, the Clinton administration did increase funds for alternative energy research, mandate new energy efficiency measures, and enforce emission standards. The major energy policy goals of the following (and current) Republican administration of President George W. Bush (2001-present) were “to increase and diversify the sources of America’s oil supplies and to make energy security a priority”3. To date, President Bush has not demonstrated an environmentally friendly agenda. He staunchly refused to sign the Kyoto Protocol, an international effort to reduce greenhouse gas emissions and air pollution. He also encouraged efforts to permit drilling in environmentally sensitive areas such as the Arctic National Wildlife Refuge in Alaska. It will be interesting to see what repercussions the Iraq war, a war he lobbied hard for against domestic and international opposition, will have on U.S. energy needs.
Engines and What Drives Them
After setting this historical perspective, we will review the internal combustion engine, which was begun in Ms. La Voie’s unit. We will discuss human’s increased dependence on engines in the last fifty years. Students will be asked to reflect on what their lives would be like without engines and machines. One activity might include a series of interviews with people who know what life was like before America was an automobile society. This could possibly involve a trip to a local retirement center or nursing home, which might jump-start a community outreach project for the students. Outputs might include essays, journal entries or even poems.
Our specific lessons on the internal combustion engine will focus on the four-stroke and two-stroke engines. We will review the premise that a gasoline-fueled engine is a mechanism designed to transform the chemical energy of burning fuel into mechanical energy. In operation, it controls and applies this energy to mow lawns, cut trees, and propel tractors, trucks and cars4. The four-stroke cycle engine is probably the most common engine type in use today. It powers almost all cars and trucks. Two stroke engines are used to power chainsaws, line trimmers, outboard motors, snowmobiles, jet-skis, light motorcycles, and model airplanes. We will discuss the specific fuel usage and the environmental impacts of the four-stroke and two-stroke engines. We will also look at the evolution of engine design, and efforts that have been made to reduce pollution.