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dams across rivers, forming large lakes and putting thousands of
acres of land under water. The water flowing over the dams
turned turbines to generate electricity. Today giant power tines
carry electricity to distant cities. Some scientists say that these
power lines are dangerous because of the electromagnetic fields
they produce. More and more people object to hydroelectric
power because it seriously changes the balance of nature.
2. Thermonuclear power, or nuclear power, comes from the
splitting of atoms. It is a widely used and inexpensive form of
energy. However, it is possibly the most dangerous because
there are health risks from radiation.
3. Coal, one type of fossil fuel, is one of the dirtiest kinds of
energy used. It heats homes and runs factories. Other fossil fuels
that come from the earth are petroleum products: gasoline,
which is used for most vehicles, and natural gas, which is used
for some vehicles, but mostly for heating and cooking. At the
present time, some New York City buses run on natural gas,
which is cleaner and cheaper than regular gasoline.
4. Alcohol is quite commonly used as fuel in Brazil. It comes
from one of Brazil's main crops, sugar cane, which is easily
processed into alcohol. Methane gas, another source of fuel,
comes from garbage, but it is not widely used. From under the
ground, Iceland gets geothermal energy, which provides most of
the country's heat and hot water. Other sources of energy include
the wind and the sun. In Hawaii, for example, the strong winds
in some locations turn giant propellers to produce electricity. In
many parts of the world the sun fulfills many energy needs.
Solar panels heated by the sun produce electricity. Solar energy
already provides many homes with heat and hot water.
5. What about future sources of energy? Ralph Hansen, a NASA
engineer and the author of Sun Power, proposed a plan to use
solar-powered satellites to capture the power of the sun in space,
where the sun shines 24 hours a day, 365 days a year. His plan
would provide low-cost, nonpolluting energy for the entire
world. An additional energy source to be developed is fusion
energy, the process that powers the sun and the stars. Nuclear
fusion, or fusion, represents an unlimited source of energy. In
fusion, nuclei combine to form bigger nuclei while releasing
energy. Not much is known about how to make it usable, but it
seems promising, and millions of dollars of government money
will help develop it. Although these sources of energy seem
easily available, their high cost is a problem. They are expensive
to develop. As a result, they are not as widely used as cheaper
forms of fuel.
6. Energy is needed to warm us, cool us, light our way, carry us
from one place to another, and process our food. If the world
population increases as expected, resources for the kinds of
energy we use today may be insufficient. We will have to look
closer at different energy sources, such as fusion and solar power.
When will we decide to spend the money necessary to develop
these energy sources? Who will pay for it? These questions will
need to be answered before we can meet our growing energy
needs.
II. Reading for main ideas.
1. Underline the word or phrase that will complete a true
statement
a. Fossil fuels include (a) nuclear energy (b) hydroelectric
power (c) petrolium/coal
b. Natural sources of energy come from (a) wind, (b) fussion (c)
alcohol.
c. The problem with most alternative sources of energy is (a) the
technology is not ready (b) the costs are too high (c) the are
limited.
2. What is your opinion? Basing your opinion on the facts in the
article tell what makes solar energy a promising source of energy.
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