Powering the Planet
The population of the planet has now exceeded seven billion. It is estimated that global energy consumption will increase by more than 25% in the next 15 years and may nearly double by 2050. But how much energy we need to use and how we harvest it depends on the choices we make now. These energy choices have an impact on the Earth’s climate. We’ve already seen the possibilities of renewable energy in the 21st century. But today, most powerful nations still rely heavily on 19th-century technology.
Some creative strategies show that the wind can power entire neighborhoods. Control, conservation and efficiency could reduce projected global energy demand by 30% by 2030. But how to do it at scale? This is not just a scientific question, it is based on political, economic, cultural, national and security decisions made by real people living in the real world.
Geologist Richard Alley is one of many climate experts to accept that ongoing human energy models on Earth are warming the planet. But he also believes the answers are out there…in the wind, in the sun, and in the minds of scientists, explorers, designers, architects and engineers.
The earth is filled with infinite energy. The oceans retain heat and generate wave and tidal energy. Plants harvest sunlight and accumulate energy in various forms. The sun heats the atmosphere and creates winds that we can use. But the biggest and most promising source of energy is the sun itself.
Sunlight that bathes the Earth’s crust provides about 120,000 terawatts. If the sun’s energy was evenly distributed around the world, it would average about 240 watts per square meter. Frank Shuman was the first scientist to invent a machine, circa 1910, that shines sunlight on metal pipes, heats liquids and drives a steam turbine. The steam powers a 75-horsepower engine that pumps water from the river to irrigate the soil.
