Environmental Engineering Reference
In-Depth Information
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Solar Energy
The sun: the star that symbolizes and provides life, power, strength, force, clarity, and,
yes, energy.
ICARUS REVISITED AT IVANPAH
In Greek mythology, Icarus attempted to escape from Crete by means of wings that
his father constructed from feathers and wax. Icarus ignored instructions not to fly
too close to the sun, and the melting wax caused him to fall into the sea where he
drowned. At the Ivanpah Solar Electric Generating System in the Mojave Desert,
near the California/Nevada border, amid miles of rock and scrub, in a windy stretch
once roamed by tortoises and coyotes, is a vast array of 7- by 10-foot solar mirrors.
From above, these mirrors create the image of an ethereal lake shimmering atop the
desert floor. A modern Icarus-like horror is played out at this site whenever birds fly
over and end up with scorched wings and bodies, or even worse for those who dive
into this faux lake and are literally fried by the 1000°F degree heat flux radiated by
the mirrors. Unfortunately, for many of these feathered victims there is no Phoenix
complex. The victims are cooked alive without hope of regeneration.
ENERGY FROM THE SUN
The sun nourishes our planet. When we consider the sun and solar energy, we
quickly realize that there is nothing new about renewable energy. The sun was the
first energy source; it has been around for 4.5 billion years, as long as anything else
we are familiar with. On Earth, without the sun, there would be nothing—absolutely
nothing. The sun provided light and heat to the first humans. During daylight, the
people searched for food. They hunted and gathered and probably stayed together
for safety. When nightfall arrived and it was dark, we can only imagine that they
huddled together for warmth and safety under the light of the stars and moon, wait-
ing for the sun and its live-giving and life-sustaining light to return.
Solar energy (a term used interchangeably with solar power) uses various tech-
nologies to take advantage of the power of the sun to produce energy. Solar energy
is one of the best renewable energy sources available because it is one the cleanest
sources of energy. Direct solar radiation absorbed in solar collectors can provide
space heating and hot water. Passive solar can be used to enhance the solar energy
used in buildings for space heating and lighting requirements. Solar energy can also
be used to produce electricity, and this is the type of green (renewable) energy that
we focus on in this section. The two major categories of solar energy technologies
are distinguished by the way they convert sunlight into electricity: photovoltaics
(PV) and concentrating solar power (CSP). These two solar electric technologies
present the greatest potential (USDOE, 2010).
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