Botkin Environmental Science Earth as Living Planet 8th txtbk

300 CHAPTER 14 Energy: Some Basics
CRITICAL THINKING ISSUE
Use of Energy Today and in 2030
Note: Before proceeding with this exercise, refer back to A Closer Look
4.1 to be sure you are comfortable with the units and big numbers.
The Organization for Economic Cooperation and Development
(OECD) is a group of 30 countries, 27 of which are classified
by the World Bank as having high-income economies. Non-
OECD members are not all low-income countries, but many are.
The developing countries (all of which are non-OECD) have
most of the world’s 6.8 billion people and are growing in population
faster than the more affluent countries. The average rate of
energy use in 2010 for an individual in non-OECD countries is
46 billion joules per person per year (1.5 kW per person), whereas
for the OECD countries it is 210 billion joules per person
per year (6.7 kW per person). In other words, people in OECD
countries use about 4.5 times more energy per person than those
in non-OECD countries. In 2010 each group—OECD and
non-OECD—used about 250 EJ (1 EJ is 10 18 J). The world average
is 74 billion joules per person per year (2.3 kW per person). 19
If the current annual population growth rate of 1.1% continues,
the world’s population will double in 64 years. However, as
we learned in Chapters 1 and 4, the human population may not
double again. It is expected to be about 8.5 billion by 2030. More
people will likely mean more energy use. People in non-OECD
countries will need to consume more energy per capita if the less
developed countries are to achieve a higher standard of living;
thus, energy consumption in non-OECD countries as a group is
projected to increase by 2030 to about 55 billion joules per person
per year (1.7 kW per person). On the other hand, energy use
in OECD countries is projected to decline to about 203 billion
joules per person per year (6.4 kW per person). This would bring
the global average in 2030 to about 80 billion joules per person
per year (2.5 kW per person), up from 74 billion joules in 2010. If
these projections are correct, 58% of the energy will be consumed
in the non-OECD countries, compared with 50% today.
With worldwide average energy use of 2.3 kW per person in
2010, the 6.8 billion people on Earth use about 16 trillion watts
annually. A projected population of 8.5 billion in 2030 with an
estimated average per capita energy use rate of 2.5 kW would use
about 21 trillion watts annually, an increase of about 33% from
today. 19
A realistic goal is for annual per capita energy use to remain
about 2.5 kW, with the world population peaking at 8.5
billion people by the year 2030. If this goal is to be achieved,
non-OECD countries will be able to increase their populations
by no more than about 50% and their energy use by about 70%;
OECD nations can increase their population by only a few percent
and will have to reduce their energy use slightly.
Critical Thinking Questions
1. Using only the data presented in this exercise, how much energy,
in exajoules, did the world use in 2010 and what would
you project global energy use to be in 2030?
2. The average person emits as heat 100 watts of power (the same
as a 100 W bulb). If we assume that 25% of it is emitted by
the brain, how much energy does your brain emit as heat in
a year? Calculate this in joules and kWh. What is the corresponding
value for all people today, and how does that value
compare with world energy use per year? Can this help explain
why a large, crowded lecture hall (independent of the professor
pontificating) might get warm over an hour?
3. Can the world supply one-third more energy by 2030 without
unacceptable environmental damage? How?
4. What would the rate of energy use be if all people on Earth
had a standard of living supported by energy use of 10 kW
per person, as in the United States today? How do these
totals compare with the present energy-use rate worldwide?
5. In what specific ways could energy be used more efficiently in
the United States? Make a list of the ways and compare your
list with those of your classmates. Then compile a class list.
6. In addition to increasing efficiency, what other changes in
energy consumption might be required to provide an average
energy-use rate in 2030 of 6.4 kW per person in OECD
countries?
7. Would you view the energy future in 2030 as a continuation
of the business-as-usual approach with more large, centralized
energy production based on fossil fuels, or a softer path,
with more use of alternative, distributed energy sources? Justify
your view.
SUMMARY
The first law of thermodynamics states that energy is
neither created nor destroyed but is always conserved
and is transformed from one kind to another. We use
the first law to keep track of the quantity of energy.
The second law of thermodynamics tells us that as
energy is used, it always goes from a more usable
(higher-quality) form to a less usable (lower-quality)
form.