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Text 10
ENERGY FOR THE FUTURE
I. Before reading
1. Say which forms of energy are most used today?
1. _________
2. _________
3. _________
4. _________
2. Read the article and say which form(s) of energy you
probably did not mention.
1. Is there really an energy crisis? Or do we depend too much on
a single form of energy? During recent generations, the world
depended mostly on hydroelectric power. Governments built
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
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