“I am ashamed at the number of things around my house and shops that are done by … human beings. Hereafter a motor must do all the chores.” – Thomas Edison
Labor Day is an opportunity to appreciate the resource of resources, energy. Energy is the capacity to do work. Work is labor, and the more done by inanimate energy, the greater the reward in terms of productivity, wealth creation, and leisure.
For much of human history, the ability to do work was limited by the strength of men, women, children, and animals. But by harnessing massive amounts of (dense) energy in machines, the amenities of modern life sprang into being.
A life of opulence once took hundreds of human helpers. Approximately 500 were required to create meals for King Louis XIV at Versailles in 1700. Today, the typical supermarket has countless more food choices than available to this ruler living in the world’s richest palace.
Today’s energy-powered transportation and communications options would be unimaginable to the wealthiest of yore. Consider the cell phone and the Internet for instant global communication. In contrast, John D. Rockefeller and leading industrialists of his era were informationally isolated.
How many human laborers would it take to approach the energy consumption of an average American? Assuming a fit person can generate a tenth of one horsepower, around 150 servants would need to be working round-the-clock. And still much could not be done.
The transition from human power to animal power to machine power has made energy the master resource. The labor-enhancing, labor-saving characteristic of energy-enabled machinery was described by resource economist Erich Zimmermann in the mid-twentieth century as follows:
The shift to machine power changed America from a rural agricultural nation to an industrial giant. It also made men’s lives easier and richer. In 1850, the average American worked seventy hours a week. Today he works forty-three. In 1850, our average American produced about 27 cents’ worth of goods an hour. Today he produces about $1.40 worth in dollars of the same purchasing power.
“By providing energy flows of high-power density, fossil fuels and electricity made it possible to embark on a large-scale industrialization,” noted energy polymath Vaclav Smil, “creating a predominantly urban civilization with unprecedented levels of economic growth reflected in better health, greater social opportunities, higher disposable incomes, expanded transportation and an overwhelming flow of information.”
The benefits of modern energy have continued to mount even since Erich Zimmermann’s day. Zimmermann was astounded that the average American in 1950 worked only 43 hours a week, compared to his grandfather’s 70 hours per week. So, where grandpa worked just about six 12-hour days, Zimmermann’s reader worked just over five eight-hour days. In July 2025, the average American worked only 34 hours per week, according to the Federal Reserve Bank of St. Louis. That is just over four 8-hour days. Imagine telling your ancestor of 1850 that, of the 168 hours in a week, his great-grandson would have to work only 34. The other 134 hours would be all his. He would assume we were all going to be aristocrats. And he would be right.
Zimmerman’s second comparison is a bit harder to calculate. Our 1850 ancestor, with one hour of work, could buy 27 cents worth of produced goods. In 1950, adjusting for inflation, Zimmermann calculated that one hour of work in America could buy $1.40 of finished goods (in 1850 dollars). Given our debased currency, the easiest way to think of it is this: In 1950, one hour of labor in America could buy five times as much as it bought in 1850. In 2025, one hour of labor can buy 10 times what it bought in 1850, and twice as much as it bought as recently as 1950.
What changed? Energy. Circa 1850, the coal-powered steam engine finally replaced the waterwheel as America’s leading source of energy. In 1859, the oil industry began in Titusville, Pennsylvania. In 1882, Edison launched the Pearl Street Station.
Labor Day is an appropriate time to recognize and appreciate energy exceptionalism. And come workday Tuesday, support public policies that make energy more plentiful, affordable, and reliable for all Americans and those around the world.
