Environmental Engineering Reference
In-Depth Information
The Enigma of Energy
By the twentieth century, scientists had learned to quantify and measure energy, yet there
remained something inherently mysterious about the concept. Richard Feynman, one of the
towering figures of modern physics, went as far as to admit that “in physics today, we have
no knowledge of what energy is” (
1970
).
Energy, as we currently understand it, is force, work and power. It is at the heart of what
it means to be alive: the ability to manipulate our environment to meet our needs. Thus,
Aristotle's definition of energy remains essentially valid today. If the father of Western
philosophy were to have stepped into a time machine that touched down on Times Square,
he would recognise around him the principle of energy in action, through two factors:
motion and work.
1.2 Energy: What Gets Lost in 'Translation'
Robert Frost memorably defined poetry as “what gets lost in translation.” Just as meaning
is inevitably lost as ideas are converted from one language to another, there is no way to
convertenergywithoutloss.Energyefficiency,liketranslation, ismerely aboutminimizing
that loss.
As a teacher, I always require that my students work in groups, where each person's
grade is influenced by that of the whole group. It often happens that a student complains
about a group-mate, typically that he or she is not pulling their weight and therefore
jeopardising the performance of the group. This reflects the second principle of
thermodynamics. The second principle states that an enclosed system naturally tends
towards maximum disorder, or entropy. Mountains are gradually worn down by wind and
water, houses need to be regularly repaired and maintained, and teenage students have a
gift for creating mayhem. Being a good student means applying a great deal of order to
one's behaviour. Yet this is an energy-consuming process. Sometimes my students opt for a
strategy that involves a much lower energy investment; instead of studying and supporting
each other, they try to sow doubt in my mind and blame each other, thus creating disorder
in the classroom.
Students are not the only ones affected by entropy. All living beings expend an
enormous amount of energy every day of their lives just maintaining the status quo. Order
is needed to survive and triumph, at least for a while, over the many external forces that
are out to get us. To live we must actively counteract the second principle, and this requires
that we expend energy. The second principle implies not only that it is far easier to destroy
(creatingdisorder)thantobuild(creatingorder)butalsothatanyconversionwillinevitably
