Page 601 - Environment: The Science Behind the Stories

In response to the prospect of lower tariffs, sales of PV promising to phase out the rest by 2022. This dramatic reduc-
modules skyrocketed as Germans rushed to lock in the old tion in electricity supply from nuclear power is causing rates to
rates. Since then, a series of reductions in the payment rates rise and puts added pressure on Germany to develop alterna-
have each spurred rushes to install more PV systems. In 2010, tive energy sources quickly.
2011, and 2012, Germans installed over 7 gigawatts of PV By developing renewable energy to replace some of its
solar capacity each year—an amount equal to the total cumu- fossil fuel use, Germany has decreased its emissions of carbon
lative capacity of the United States. In 2012 the government dioxide by 140 million tons per year—equal to taking 24 million
proposed to end subsidies once the nation reaches 52 giga- cars off the road. Since 1990, carbon dioxide emissions from
watts of cumulative capacity, roughly twice its total as of 2011. German energy sources have fallen by 24%, and emissions of
By reducing the subsidies gradually, the government aims seven other major pollutants (CH , N O, SO , NO , CO, VOCs,
X
4
2
2
to create a stronger solar industry that can sustain growth over and dust) have been reduced by 12–95%. At least half of these
the long term and can compete with foreign companies for reductions are thought to be due to renewable energy paid for
international business. Indeed, boosted by domestic demand, under the feed-in tariff system.
German industries have become global leaders in “green tech,” Germany’s success is serving as a model for other coun-
designing and selling renewable energy technologies around tries in Europe and around the world. As of 2013, more than
the world. Germany is second in PV production behind China, 90 nations had implemented some sort of feed-in tariff. Spain
leads the world in production of biodiesel, and has developed and Italy ignited their wind and solar development as a result.
several cellulosic ethanol (p. 590) facilities. Renewable energy In North America, Vermont and Ontario established feed-in
industries in Germany today employ nearly 400,000 citizens. tariff systems similar to Germany’s, while California, Hawaii,
By 2020, Germany aims to obtain 35% of its electricity Oregon, Washington, and New York conduct more-limited
from renewable sources, and plans to increase this percent- programs. In 2010, Gainesville, Florida, became the first U.S.
age to 50% by 2030, 65% by 2040, and 80% by 2050. To city to establish feed-in tariffs, and solar power is growing
make this happen, the government has been allotting more quickly there as a result. Moreover, utilities in 46 U.S. states
public money to renewable energy than any other nation—over now offer net metering, in which utilities credit customers who
$25 billion annually in recent years. Following the Fukushima produce renewable power and feed it into the grid. As more
nuclear disaster in Japan in 2011 (pp. 40–41, 578–579), the nations, states, and cities encourage renewable energy, we
German government responded to anti-nuclear demonstra- may soon experience a historic transition in the way we meet
tions by shutting down 7 of its 15 nuclear power plants and our energy demands.

“New” Renewable Energy New renewable sources are growing fast
Sources As with other energy sources, the new renewables provide
energy for three types of applications: (1) to generate elec-
Germany’s bold federal policy is just one facet of a global tricity, (2) to heat air or water, and (3) to fuel vehicles. Their
shift toward renewable energy. Across the world, nations potential is enormous, yet so far their contribution to our soci-
are searching for ways to move away from fossil fuels while ety’s overall energy budget remains small. Today we obtain
ensuring a reliable and affordable supply of energy for their just 1% of our global energy from the new renewable energy
economies. This is because the economic and social costs, sources. Fossil fuels provide 81% of the world’s energy and
security risks, and health and environmental impacts of fossil nuclear power provides 6%, while biomass and hydropower
fuel dependence (Chapter 19) are all continuing to intensify. supply nearly all of the 13% that renewable energy sources
The two renewable energy sources that are most devel- provide (see Figure 20.1a, p. 572).
oped and widely used are bioenergy, the energy from com- The new renewables make a similarly small contribu-
bustion of biomass (wood and other plant matter), and tion to our global generation of electricity thus far (see Fig-
hydropower, the energy from running water (Chapter 20). ure 20.1b, p. 572). Only 20% of our electricity comes from
These conventional alternatives to fossil fuels are renewable, renewable energy, and hydropower accounts for four-fifths of
but they can be depleted with overuse and exert some undesir- this amount.
able environmental impacts. Nations and regions vary in the renewable sources they
In this chapter we explore a group of alternative energy use. In the United States, most renewable energy comes from
sources that are often called “new renewables.” These diverse biomass and hydropower. As of 2012, wind power accounted
sources include energy from the sun, from wind, from Earth’s for 15%, solar energy for 3%, and geothermal energy for 3%
geothermal heat, and from ocean water. These energy sources (Figure 21.1a). Of electricity generated in the United States
are not truly new. In fact, they are as old as our planet, and from renewables, hydropower accounts for most, while as of
people have used them for millennia. We commonly refer to 2012 wind power accounted for 29%, geothermal for 3%, and
them as “new” because (1) they are just beginning to be used solar for just 1% (Figure 21.1b).
on a wide scale in our modern industrial society, (2) they are Although they comprise a small proportion of our
harnessed using technologies still in a rapid phase of develop- energy budget, the new renewable energy sources are grow-
ment, and (3) they will likely play much larger roles in the ing quickly. Over the past four decades, solar, wind, and
600 future. geothermal energy sources have grown far faster than has

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