Sources of power such as fossil fuels, nuclear energy, and the sun are essential for modern civilization. In this high-interest video, we learn about the history of earth’s energy resources. This video is one of the three part series NOVA: Treasures of the Earth: Gems
The importance of energy for modern life is underscored by a visit to the Ravenswood Generating Station, or “Big Alice”, a power plant the provides much of the electricity for New York City. Today, the station burns natural gas to power its electricity generating turbines. It once used coal, a fossil fuel resource of past importance.
Fossil fuels helped to make modern civilization possible. Coal formed from the remains of plants in ancient swamps. The weight of overlying layers compressed the organic remains into a black rock of nearly pure carbon. A lump of coal can be likened to a charged battery. The potential energy stored in the coal can be released through burning.
Starting in the 1700s, the exploitation of coal enabled the potential of individual workers to be multiplied. Burning coal was used as a power source in factories and later electrical power plants. The heat from burning coal was used to drive turbines, devices that convert the chemical energy stored in coal into mechanical and electrical energy. Coal was the original fuel of the industrial revolution, and it helped to elevate the life of the average worker from a “nasty, brutish” existence into one of greater prosperity.
The next great fossil fuel resource was oil or petroleum. Today, oil is refined into gasoline to drive our cars. Oil is still pumped today in California. Many of today’s power plants burn natural gas, the cheapest and cleanest fossil fuel resource. Natural gas helps to mitigate some of the negative effects of fossil fuel usage such as air pollution and man-influenced climate change. Scientists have linked carbon introduced through fossil fuel burning to climate change and global warming. The carbon dioxide gas created by burning fossil fuels is considered a “greenhouse” gas, and it helps to trap the sun’s heat in earth’s atmosphere. A warmer earth has led to an increase in global sea level, the melting of earth’s glaciers, and the damage and degradation of the ocean’s coral reefs.
The problem of climate change has spurred efforts to find alternative energy sources. The sun emits tremendous amounts of “free” energy as it fuses hydrogen into helium at its core. Cloudy weather, and the expense of creating solar panels, has led to experiments to mitigate these situations. In China, large arrays of rechargeable batteries are being tested to store energy during periods of cloudy weather. Chinese scientists are also working to lower the cost and increase the efficiency of solar panels. The horrific air pollution in Chinese cities has encouraged these efforts to replace coal-burning power plants.
Another power source already in use, nuclear energy, is also being reassessed in today’s world of global warming. Nuclear power utilizes energy from ancient stars that died in titanic supernova explosions that occurred before the earth's formation. In brief instances of incredible temperature, heavy elements such as uranium were fused in these ancient dying stars. Today, it is realized that heavy elements such as gold and uranium formed when neutron stars, the remnants of stars that previously went supernova, spiral together and collide. Despite having an “image problem” due to its use in bombs, and nuclear accidents in Russia, Japan, and the United States, nuclear energy can provide carbon-free energy. We are introduced to uranium by Taylor Wilson, a young nuclear scientist famous for creating a nuclear reactor at the age of 14! One pound of uranium fuel is the energy equivalent of 3 million pounds of coal. If the safety issues inherent in nuclear power generation can be solved, it will provide a viable substitute for fossil fuels and help to mitigate climate change.
The PDF contains a two-sided video worksheet consisting of 49 multiple choice and true-or-false questions, along with an answer key, and an MS Word download link. You will need to obtain a DVD of the video, use the PBS Internet site, or YouTube