Page 567 - Environment: The Science Behind the Stories

54.5 mpg by 2025. If this strong improvement comes to pass, it drive more because he or she feels it’s okay to do so now that
will enable a huge reduction in oil use. New technologies will less gas is being used per mile. This phenomenon is called the
add over $2000 to the average price of a car, but drivers will rebound effect, and studies indicate that it is widespread and
save perhaps $6000 in fuel costs over the car’s lifetime. significant. In some instances, the rebound effect may com-
In 2009, Congress and the Obama administration took pletely erase efficiency gains, and attempts at energy efficiency
another major step to improve automobile fuel efficiency may end up actually causing greater energy consumption! As
while stimulating economic activity and saving jobs during our society pursues energy efficiency in more and more ways,
a severe recession. The popular “Cash for Clunkers” pro- this will be an important factor to consider.
gram—formally named the Consumer Assistance to Recycle
and Save (CARS) Act—paid Americans $3500 or $4500 each
to turn in old vehicles and purchase newer, more fuel-efficient We need both conservation and renewable
ones. The $3-billion program subsidized the sale or lease of energy
678,000 vehicles averaging 24.9 mpg that replaced vehicles
averaging 15.8 mpg. It is estimated that 824 million gallons of Despite concerns over the rebound effect, energy efficiency
gasoline will be saved as a result, preventing 9 million metric and conservation efforts are vital to creating a sustainable
tons of greenhouse gas emissions and creating social benefits future for our society. It is often said that reducing our
worth $278 million. energy use is equivalent to finding a new oil reserve. Some
U.S. policymakers could do still more to encourage estimates hold that effective energy conservation and effi-
oil conservation. So far the United States has kept its taxes ciency in the United States could save 6 million barrels of oil
on gasoline extremely low, relative to most other nations. a day—nearly the amount gained from all offshore drilling,
Americans pay two to three times less per gallon of gas than and considerably more than would be gained from Canada’s
drivers in many European countries. In fact, gasoline in the oil sands. In fact, conserving energy is better than finding a
United States is sold more cheaply than bottled water! As new reserve because it alleviates health and environmental
a result, U.S. gasoline prices do not account for the sub- impacts while at the same time extending our future access
stantial external costs (pp. 164, 183) that oil production and to fossil fuels.
consumption impose on society. Some experts have esti- Yet regardless of how effectively we conserve, we will
mated that if all costs to society were taken into account, still need energy to power our civilization, and it will need to
the price of gasoline would exceed $13/gallon. Instead, our come from somewhere. Most energy experts feel that the only
artificially low gas prices diminish our economic incentives sustainable way of guaranteeing ourselves a reliable long-term
to conserve. supply of energy is to ensure sufficiently rapid development of
renewable energy sources (Chapters 20 and 21).

WEIGHING THE ISSUES Conclusion
MORE MILES, LESS GAS If you drive an automobile, what
gas mileage does it get? How does it compare to the vehicle Over the past two centuries, fossil fuels have helped us build
averages in Figure 19.27? If your vehicle’s fuel efficiency were the complex industrialized societies we enjoy today. Yet
10 mpg greater, and if you drove the same amount, how many sometime soon our production of conventional fossil fuels
gallons of gasoline would you no longer need to purchase will begin to decline. We can respond to this challenge by
each year? How much money would you save? seeking out new sources of fossil fuels and continuing our
Do you think the U.S. government should mandate fur- way of life but paying ever-higher economic, health, and
ther increases in the CAFE standards? Should the government environmental costs. Or, we can encourage conservation and
raise taxes on gasoline sales as an incentive for consumers efficiency while aggressively developing alternative clean
to conserve energy? What effects (on economics, on health, and renewable energy sources. The path we choose will have
and on environmental quality, for instance) might each of these far-reaching consequences for human health and well-being,
steps have? for Earth’s climate, and for the stability and progress of our
civilization.
The debate over the Canadian oil sands and the Keystone
The rebound effect cuts into XL pipeline is a microcosm of this debate over our energy
efficiency gains future. Fortunately, we are not caught in a simple trade-off
between fossil fuels’ economic benefits and their impacts on
Energy efficiency is a vital pursuit, but it may not always save the environment, climate, and health. Instead, as renewable
as much energy as we expect. This is because gains in effi- energy sources become increasingly feasible and economical,
ciency from better technology can be partly offset if people it becomes easier to envision freeing ourselves from a reliance
engage in more energy-consuming behavior as a result. For on fossil fuels and charting a bright future for humanity and
instance, a person who buys a fuel-efficient car may choose to the planet with renewable energy.

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