For the majority of human history, people used their own muscles to provide almost all of the work required for survival and development. A thin slice of humanity achieved a moderate amount of personal comfort and leisure because they were able, often through an accident of birth, to control a portion of the daily work output of hundreds to thousands of their fellow humans. The only sources of work—in the engineering sense—that were not either human or animal muscle came from capturing falling water or intermittently by capturing the breezes through devices like cloth sails or wind mills.
Humans understood fire. They used it to keep warm, to process their food, to produce some implements from metal, and as a weapon of destruction. It was not, however, until inventive people with names like Savery, Newcomen, and Watt started to work out ways of using the useful vapor (steam) produced when fire boiled water that humans learned how to become masters of the earth’s vast store of combustible materials.
The seemingly simple act of boiling water provided humans the means necessary to gradually invent and manufacture their way out of a life of drudgery. Steam power was the key; H2O had always been important for people, but when they learned to pump it as a liquid, heat it into a pressurized gas, and condense it back down into a liquid, H2O became the vital working fluid that could turn heat into work and force machines to become the drudges in service of human beings.
It is not an exaggeration to note that without the act of boiling water to create and use steam, getting rid of serfdom and slavery would have been virtually impossible. One of the inspirational books in my personal library, titled “Power from Steam: A History of the Stationary Steam Engine,” has a chapter titled “The Noblest Machine” that leads with a quote from an influential author from the 1880s:
England is the birth-place of the steam engine. Its invention has been a grand triumph over the material which nature has placed at our disposal. There is no limit to the sphere of its usefulness, nor can anyone measure the benefits which directly and indirectly accrue to society from its employment.
Though internal combustion engines have replaced steam engines in almost every machine that most people ever see, steam is still the working fluid for a very important class of machines. Approximately 70–80 percent of the world’s electrical power comes from machinery that uses heat from either combustion or fission to boil water. The resulting steam spins turbines that rotate conductors through magnetic fields and create the current that is the lifeblood of modern society.
Every year, humans dig up, transport, and burn more than 7,800,000,000 tons of coal, most of which is consumed in the deceptively simple activity of boiling water to create steam. Modern societies also consume millions of tons of natural gas, oil, and wood every year producing steam. Boiling water is still a foundational process that enables people in developed countries to live, study, work, and play with a leisure enabled by harnessing a variety of heat sources to be their mechanical slaves.
Unfortunately, most people do not understand just how large a debt they owe to those thousands of engineers and material scientists who figured out how to safely boil water, capture the resulting vapors at enormously high pressures, and efficiently use that high-energy fluid to spin turbines.
Not very many people in modern societies have actually seen steam machinery in action, have measured its temperature and pressure, or have seen how destructive it can be if not handled with the utmost care. Because of the efforts of organizations like the American Society of Mechanical Engineers, which has worked hard for about 100 years to develop and document the technical codes that prevent boiler explosions, most people take steam power for granted.
In fact, one of the frequently used phrases used in disrespect of nuclear energy is that it is “essentially a very complicated way to boil water”. One of the fiercest and most effective nuclear energy opponent, Ralph Nader, used to use a similar phrase with depressing regularity. My interpretation of the way that people use the phrase is that they expect their audience to think, “Heck, anyone can boil water, you just turn on the stove and it happens. Why do you need to make it complicated?”
I would bet that most of the people who nod their heads at that phrase have never had to cut and carry enough wood to boil a large pot of water. I am sure that few have ever spent much time watching a coal conveyor steadily feed a large boiler that is producing some of the electricity that feeds the sockets and stoves in their homes. Boiling water is not only important, but it is not as simple as it may seem. It generally requires the consumption of a vast quantity of increasingly expensive materials and it requires a tacit agreement on the part of everyone in the area of the fire to accept their share of the waste products that are spread far and wide from every fire.
The exception to that general rule is the water that gets boiled by the heat released from atomic fission. Once the work of the talented engineers and builders is complete, operating a fission heated boiler is a rather simple task. The task is not made simple by complex automation or hard working pumps and conveyors, it is enabled by physics. Once a moderate amount of fuel is loaded into a nuclear reactor, it will reliably and simply produce heat for somewhere between 18 months and 33 years (for a Virginia class submarine) with relatively little additional effort.
That fuel is not even terribly expensive; the average fuel cost for a nuclear plant operating in the United States is just 0.75 cents for every kilowatt-hour generated. Even “cheap” coal costs about three times that amount, and natural gas can cost about 3-50 times as much per unit of electricity produced depending on when and where that gas needs to be delivered. The average total production costs (fuel plus operations and maintenance) for a U.S. nuclear power plant in 2012 was just 2.4 cents per kilowatt hour.
The fact is that nuclear energy is a cheap, clean, simple, elegant way to perform the vital act of boiling water.
ANS Nuclear Cafe published the above commentary on February 1, 2011 with the title Nuclear energy is a disruptively cheap and simple way to boil water. I updated the cost figures in the penultimate paragraph with the latest available numbers and made a few other small revisions.
I’m reintroducing it to lay the groundwork for a follow-on piece about using nuclear heat as a replacement for combustion heat in applications that do not necessarily involve boiling water, as important as that activity has been for industrial development.