Why Are We Concerned?
Introduction
Texting your friends, shopping for new clothes, listening to your favorite song – for
almost everything you do, you rely on energy. In the future will there be enough
energy to meet all of our needs and wants? What changes will occur over the next
10, 20, or 50 years? Why should we be concerned? When thinking about energy
today, there are two main concerns. Greenhouse gas emissions are having an effect
on our climate. There is also an increase in demand for energy due to population
and economic growth.
Greenhouse Gas Emissions and Global Climate Change
Greenhouse gases, such as carbon dioxide (CO2), methane (CH4) and water vapor,
are gases that let sunlight into the atmosphere. When the sunlight hits the earth’s
surface, some of its heat is reflected back toward space. Greenhouse gases absorb
this heat and trap it in the atmosphere. The temperature of the earth would stay just
about constant if the amount of energy sent from the sun to the earth was almost the
same as the amount of heat reflected back toward space. Without greenhouse
gases the earth would not be warm enough for us to live. However, the
concentration of greenhouse gases in the atmosphere is increasing and the
temperature of the earth is increasing. This increase is caused in part by
greenhouse gases that are released by burning fossil fuels, such as coal, petroleum,
and natural gas. Concentration of carbon dioxide in the atmosphere has risen 35%
since the start of the Industrial Revolution. Between the years 2000 and 2025, global
greenhouse gas emissions are projected to rise 57%. We rely mainly on fossil fuels
for our energy. Therefore, greenhouse gas emissions result from most of our daily
activities.
Population and Economic Growth
The countries that tend to emit the most greenhouse gases are countries with large
populations, large economies, or both. A country’s economy is its system of
producing, distributing, and consuming wealth. In years to come, populations are
expected to increase. Economic growth, especially in developing countries, will
place the greatest demand on global energy resources ever experienced.
By the year 2030:
 The world’s population is expected to be about one third larger than it is
today. That’s two billion more people.
 The energy demand worldwide is projected to be more than 50% higher than
it was in 2006, with most of that growth coming from developing Asian
countries, especially China and India.
 Today only 12% of the people in the world own automobiles. As the
population increases and economies thrive, more people are expected to own
© 2011 Project Lead The Way, Inc.
GTT-EE Activity 3.2.1 Why Are We Concerned? – Page 1
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automobiles. Almost all of the energy used to power automobiles today
comes from petroleum. However, it is not likely that petroleum alone is going
to be able to supply all of the world’s growing automotive energy needs.
We must find a way to meet the demand for more energy. Yet we also must
address long-term concerns about the environment.
In this activity you will graph the past, present, and predicted future use of our
energy sources.
Equipment
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Evernote
Computer with Internet access and spreadsheet program
Procedure
Use the Internet to research and then create appropriate graphs to answer the
following questions.
1. How has the consumption of energy per person changed over the last 50 years?
2. How has the percentage of energy we import from other countries changed in the
last 50 years?
3. How has the mix of energy sources changed in the last 50 years in production
and consumption? Consider renewable, exhaustible, and inexhaustible sources.
4. Use your graphs to answer the questions in the conclusion section below.
Conclusion
1. Describe a trend that you notice in your graphs.
2. Was there a historical event that affected the trend you just described?
3. Why do you think CO2 emissions have been increasing since the industrial
revolution?
© 2011 Project Lead The Way, Inc.
GTT-EE Activity 3.2.1 Why Are We Concerned? – Page 2
4. If we continue to meet our energy needs with fossil fuels, what might be different
about the way we live in 2030 and why?
5. How would the implementation of a Smart Grid affect our lives?
© 2011 Project Lead The Way, Inc.
GTT-EE Activity 3.2.1 Why Are We Concerned? – Page 3