302
B
y the late 19th century, fears
were already growing in
industrial Europe that the
world could not rely on fossil fuels
forever. When the first working
selenium solar cell panel was built
in 1883 by American inventor
Charles Fritts, the progressive
German industrialist Werner von
Siemens immediately recognized its
huge potential for renewable energy.
He declared: “the supply of solar
energy is both without limit and
without cost.” Yet, because no one
at the time understood exactly how
selenium created photoelectricity,
and Siemens’s calls for more
experiments went unheeded, solar
cells were not developed until the
1950s. Today, solar power is the
fastest growing source of new
energy and predicted to dominate
future growth in renewables.Renewables v. fossil fuels
Human civilizations have drawn
on renewable energy for millennia—
from burning firewood to
harnessing the wind to propel
sailing ships. Renewable sources
such as sunlight or tidal power
are not at all depleted by use.By contrast, fossil fuels—such
as coal, oil, and gas—have taken
thousands of years to form, and
when exhausted, cannot be
replaced. Natural gas is an
abundant fossil fuel, but its
extraction can cause environmental
problems, such as earth tremors
and water contamination. Nuclear
power, although sustainable for a
long period of time, is not considered
renewable because its production
requires a rare type of uranium ore.
Energy sources such as solar
power, wind, and water are also
generally “clean”—unlike fossil fuels,
they produce zero or very low
greenhouse gas emissions. However,
not all renewables are clean. People
have burned wood and animal dung
for heat and light for hundreds of
thousands of years. Trees can be
replanted and animals produce more
dung, so the practice is sustainable,
but burning such fuels also emits
carbon dioxide (CO 2 ), which is oneRENEWABLE ENERGY
IN CONTEXT
KEY FIGURE
Werner von Siemens
(1816–92)BEFORE
2nd century bce The first
water wheels mark a labor-
saving turning point in the
history of technology.1839 French physicist Edmond
Becquerel creates the first
photovoltaic cell, using light to
produce a weak voltage.1873 French inventor Augustin
Mouchot warns that fossil fuels
will run out in the future.1879 The first hydroelectric
power plant is built at Niagara
Falls in the United States.AFTER
1951 Construction of the first
grid-connected nuclear power
plant begins at Obninsk in the
USSR. It produced electricity
from 1954 to 1959.1954 Bell Laboratories in the
US develop the first practical
silicon photovoltaic cell.1956 American geologist
Marion King Hubbert predicts
declining oil production after
the year 2000.1966 The world’s first tidal
power station starts operating
on the Rance River in France.2018 The International Energy
Agency predicts that the share
of renewables in meeting
global energy demands will
increase by a fifth to reach
12.4 percent in 2023.The Ivanpah solar plant in the
Mojave Desert, California, generates
enough concentrated solar power
to serve more than 140,000 homes
at peak hours of the day.US_300-305_Renewable_energy.indd 302 12/11/18 6:26 PM