Why is the steam engine important?

Heat water to its boiling point and it changes from being a liquid to become the gas or water vapor we know as steam. When water becomes steam its volume increases about 1,600 times, that expansion is full of energy.

An engine is a machine that converts energy into mechanical force or motion that can turn pistons and wheels. The purpose of an engine is to provide power, a steam engine provides mechanical power by using the energy of steam.

Steam engines were the first successful engines invented and were the driving force behind the industrial revolution. They have been used to power the first trains, ships, factories, and even cars. And while steam engines were definitely important in the past, they also now have a new future in supplying us with power with geothermal energy sources.

How Steam Engines Work

To understand a basic steam engine, let's take the example of the steam engine found in an old steam locomotive like the one depicted. The basic parts of the steam engine in a locomotive would be a boiler, slide valve, cylinder, steam reservoir, piston, and a drive wheel.

In the boiler, there would be a firebox where coal would be shoveled into. The coal would be kept burning at a very high temperature and used to heat the boiler to boil water producing high-pressure steam. The high-pressure steam expands and exits the boiler via steam pipes into the steam reservoir. The steam is then controlled by a slide valve to move into a cylinder to push the piston. The pressure of the steam energy pushing the piston turns the drive wheel in a circle, creating motion for the locomotive.

History of Steam Engines

Humans have been aware of the power of steam for centuries. Greek engineer, Hero of Alexandria (circa 100 AD), experimented with steam and invented the aeolipile, the first but very crude steam engine. The aeolipile was a metal sphere mounted on top of a boiling water kettle. The steam traveled through pipes to the sphere. Two L-shaped tubes on opposite sides of the sphere released the steam, which gave a thrust to the sphere that caused it to rotate. However, Hero never realized the potential of the aeolipile, and centuries were to pass before a practical steam engine would be invented.

In 1698, English engineer, Thomas Savery patented the first crude steam engine. Savery used his invention to pump water out of a coal mine. In 1712, English engineer and blacksmith, Thomas Newcomen invented the atmospheric steam engine. The purpose of Newcomen's steam engine was also to remove water from mines. In 1765, a Scottish engineer, James Watt began studying Thomas Newcomen's steam engine and invented an improved version. It was Watt's engine that was the first to have a rotary motion. James Watt's design was the one that succeeded and the use of steam engines became widespread.

Steam engines' had a profound effect on the history of transportation. By the late 1700s, inventors realized that steam engines could power boats and the first commercially successful steamship was invented by George Stephenson. After 1900, gasoline and diesel internal combustion engines began replacing the steam piston engines. However, steam engines have reappeared in the last twenty years.

Steam Engines Today

It may be surprising to know that 95 percent of nuclear power plants use steam engines to generate power. Yes, the radioactive fuel rods in a nuclear power plant are used just like coal in a steam locomotive to boil water and create steam energy. However, the disposal of spent radioactive fuel rods, the vulnerability of the nuclear power plants to earthquakes and other issues leaves the public and the environment at great risk.

Geothermal power is power generated using steam produced by heat emanating from the molten core of the earth. Geothermal power plants are relatively green technology. Kaldara Green Energy, a Norwegian/Icelandic manufacturer of geothermal electrical power production equipment, has been the major innovator in the field.

Solar thermal power plants can also use steam turbines to generate their power.

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Bellis, Mary. "How Do Steam Engines Work?" ThoughtCo. https://www.thoughtco.com/steam-engines-history-1991933 (accessed December 17, 2022).

Steam engines found many uses in a variety of industries, most notably mining and transportation, but its popularization shaped nearly every aspect of the industrial society, including where people could live, labor, and travel;  how goods were produced, marketed, and sold; and what technological innovations followed.

Learning Objective

Give examples of the industries powered by steam

Key Points

• The steam engine was one of the most important technologies of the Industrial Revolution, inspiring other innovations and initiating further technological advancements. In 1775, James Watt formed an engine-building and engineering partnership with manufacturer Matthew Boulton. This served as a kind of creative technical center for much of the British economy. They supported talents and other companies, creating a culture where firms often shared information that they could use to create new techniques or products.
• From mines to mills, steam engines found many uses in a variety of industries. The introduction of steam engines improved productivity and technology and allowed the creation of smaller and better engines. Around the start of the 19th century, Cornish engineer Richard Trevithick and American Oliver Evans began to construct higher-pressure non-condensing steam engines, exhausting against the atmosphere. After Trevithick’s development, transport applications became possible and steam engines found their way into boats, railways, farms, and road vehicles.
• The steam engine was originally invented and perfected to be used in mines. The introduction of the steam pump by Savery in 1698 and the Newcomen steam engine in 1712 greatly facilitated the removal of water and enabled shafts to be made deeper, enabling more coal to be extracted. The adoption of John Smeaton’s improvements to the Newcomen engine followed by James Watt’s more efficient steam engines from the 1770s reduced the fuel costs of engines, making mines more profitable.
• Steam locomotives were invented after the introduction of high pressure steam engines when the Boulton and Watt patent expired in 1800. Steam-hauled public railways began with the Stockton and Darlington Railway in 1825. The use of steam engines on railroads proved extraordinary since large amounts of goods and raw materials could now be delivered to cities and factories alike at a fraction of the cost traveling by wagon.
• Following the advent of the steamboat, the United States saw an incredible growth in the transportation of goods and people, which was key in westward expansion. The steamboat dramatically reduced time used to transport goods and allowed for increased specialization. The steamboat was also critical to facilitating the internal slave trade. With the steamboat came the need for an improved river system and infrastructure along the rivers.
• Steam engines are a particularly illustrative example of how changes brought by industrialization led to even more changes in other area.Water power, the world’s preceding supply of power, continued to be an essential source even during the height of steam engine popularity. The steam engine, however, provided many novel benefits. While many consider the potential for an increase in power generated o be the dominant benefit (with the average horsepower of steam powered mills producing four times the power of water powered mills), others favor the potential for agglomeration. Steam engines made it possible to easily work, live, produce, market, specialize, and viably expand without having to worry about the less abundant presence of waterways. Cities and towns were now built around factories, where steam engines served as the foundation for the livelihood of many of the citizens. By promoting the agglomeration of individuals, successful local markets were established. Cities quickly grew and the quality of living eventually increased as infrastructure was put in place. Finer goods could be produced as acquisition of materials became less difficult and expensive. Direct local competition led to higher degrees of specialization and labor and capital were in rich supply. The steam-powered towns encouraged growth both locally and on the national scale.

  What is the importance of the steam engine?

  The introduction of steam engines improved productivity and technology, and allowed the creation of smaller and better engines. After Richard Trevithick's development of the high-pressure engine, transport applications became possible, and steam engines found their way to boats, railways, farms and road vehicles.

  How did steam engine impact society?

  Steam engines made it possible to easily work, live, produce, market, specialize, and viably expand without having to worry about the less abundant presence of waterways. Cities and towns were now built around factories, where steam engines served as the foundation for the livelihood of many of the citizens.

  Why was the steam engine important to the industrial?

  Steam power became the energy source for many machines and vehicles, making it cheaper and easier to produce commodities in large amounts. This in turn increased the demand for raw materials used to build more machines that can produce even more commodities.

  Why were steam trains so important?

  The steam engine was central to the industrial revolution. Only through providing a convenient source of energy could major forms of transportation grow and prosper. Steamships and steam locomotives allowed for the quicker transportation of raw materials that could be used to produce finished goods.