Environmental Engineering Reference
In-Depth Information
by machines. Those machines live on energy—
their
ability to act—and without energy, they are the same
as the energy-starved machines that can't save the Gambian babies: useless.
And we desperately need machines to do work for us because we are naturally
very weak.
Without ma-
chines to help us, we don't have anywhere near all the energy that we need to survive and flourish.
The average human being needs about 2,000 calories a day to give him enough energy to do everything
he needs to do—from going to the office to taking a walk to manual labor to sleeping. That's equal to
2,326 watt-hours, which is the amount of energy it takes to power a 100-watt lightbulb for 23.26 hours.
Essentially, your body uses the same amount of energy as a 100-watt lightbulb. Pretty interesting, right?
The more physical work you need to do, the more calories you use. A farmer doing vigorous physical
work for a day might exert 4,000 calories.
3
An Olympic athlete like Michael Phelps might use 8,000 cal-
ories of energy a day.
4
The more energy you are using at any time, the more
power
you are exerting. Power is defined as the
rate of energy use. Power is energy in action; the gasoline is the energy, the engine turns it into power.
And here's where the problem of human weakness comes in. We are not very powerful—about one
tenth as powerful as a horse that's one two-hundredth the power of the average car—and thus we can use
only so much energy and do only so much work, not nearly enough for a good standard of living.
The story of energy for over 99 percent of history is that human beings couldn't get enough of it to live,
and if they could, they could make very limited use of it, because they lacked
power
. Thus they spent their
lives engaging in grueling physical labor just to keep their bodies going long enough to engage in the next
day of grueling physical labor.
Now if we were all like Superman, it would be a different story. Imagine if Superman, instead of de-
voting himself to saving Lois Lane and others, decided to help poor countries industrialize. He would be
amazing! Superman's superpower, after all, is
power
. He is a high-powered machine that stores a lot of
energy in his body. He can melt iron, forge steel, plow fields, build buildings, even run an electrical system
by turning some sort of especially large crank.
He could transform any place for the better.
And so can we, with enough energy and high-powered machines. Using human ingenuity, we have
made ourselves into supermen.
Consider the amount of energy at the average American's disposal. The average American's total ma-
chine energy use is 186,000 calories a day—ninety-three humans (or twenty-three Michael Phelpses)!
5
This is one of the greatest achievements in human history. In the past, before modern energy technology,
the main way to overcome the problem of human weakness was putting others into a state of servitude or
slavery—which meant that only some could prosper, and at the great expense of others. But with machine
energy and machine servants, no one has to suffer; in fact, the more people, the merrier.
ThemostmemorablesummaryI'vereadaboutthisamazingdevelopmentisbyeconomistMiltonFried-
man:
Industrial progress, mechanical improvement, all of the great wonders of the modern era have meant
little to the wealthy. The rich in ancient Greece would have benefited hardly at all from modern plumb-
ing—running servants replaced running water. Television and radio—the patricians of Rome could en-
joy the leading musicians and actors in their home, could have the leading artists as domestic retainers.
Ready-to-wear clothing, supermarkets—all these and many other modern developments would have
added little to their life. They would have welcomed the improvements in transportation and in medi-
cine, but for the rest, the great achievements of western capitalism have redounded primarily to the
