Energy Use—Chapter 1:
Without energy, nothing happens. With energy, things start happening. An intricate web of energy connects everything. The sound of rain on the leaves, the sound of a waterfall, and the sound of a rock concert are all related. Here’s how . . .
The Sun shines on oceans, rivers, lakes, and sunbathers wet from a swim. Water, absorbing the Sun’s energy, becomes vapor, and is carried by the wind. It returns to Earth as rain or snow. Some of it falls in sections of North America and drains through rivers and streams into the Great Lakes. Each minute 379,000 tons of this water tumbles over Niagara Falls, dropping more than 160 feet, accelerating by the force of gravity to nearly 70 mph. The energy of this tumbling mass is transformed to heat and tremendous noise as the water crashes below. Tunnels upstream from the falls divert some of the water through powerful water turbines which drive some of the largest electrical generators in the world. Electricity flows through wires to supply the energy needs of millions of people, including those enjoying the sounds from a band’s amplifiers at a rock concert.
All living things need energy for growth, reproduction, survival, and comfort. In channeling energy, each species changes its environment. Changes can happen quickly, as when a beaver’s dam turns a woodland valley into a pond. Changes can be slower and more far-reaching, as when microbes on the shores of ancient oceans transformed our planet’s atmosphere from suffocating gases into the oxygen-rich air that supports life today. Humans have the ability to rapidly and profoundly change the environment through their use of energy.
Our ways of channeling energy have important side effects. People who wash their clothes by the river bank and dry them in the Sun affect the environment differently from those who use electric washers and dryers. Thousands of morning commuters in cars affect the environment differently from people who go on foot.
The standard of living of industrialized nations is built on a use of energy many times higher than that of the non-industrialized world, and many times higher than at any other time in history. Side effects of this energy use include increases in air and water pollution, with associated health problems. Also, our current energy use produces large quantities of carbon dioxide which may bring about planet-wide climate changes from an increased greenhouse effect and global warming.
Since the beginning of the Industrial Revolution more than 150 years ago, the ways people use energy have changed, and the pace of change has increased. We can easily divide the history of energy sources into three eras.
In the past few decades other energy sources, including nuclear and hydroelectric power have been added to the energy source pie. Hydroelectric power is the harnessing of the energy of rivers, such as at Niagara Falls. Nuclear power harnesses the energy stored within atoms. Nuclear power, aside from nuclear bombs, is used to generate electricity.
Side Effects of Our Energy Use
Today, the average person uses far more energy than that person’s grandparents used—and there are more people alive today than ever before. Since we rely mostly on oil, coal, and gas, our energy use generates serious problems, including the following.
• Pollution from burning fuel causes health problems.
We can help to limit our effects on the environment by learning how to use energy wisely. However, wisdom does not come from memorizing a few simple rules. There will be many choices related to energy use in the future—including some that we cannot even imagine today. In order to acquire the wisdom to make the right choices, it will be important to learn about how people use energy now. That’s what this book is all about.
Humans and Energy
(video segment from Earth: The Operator's Manual)
Back to the top
NEXT CHAPTER >>