Humanities ? History & Culture The History of the Refrigerator Share Flipboard Email Print Sean Malyon / Getty Images History & Culture Inventions Famous Inventions Famous Inventors Patents & Trademarks Invention Timelines Computers & The Internet American History African American History African History Ancient History and Culture Asian History European History Genealogy Latin American History Medieval & Renaissance History Military History The 20th Century Women's History View More By Mary Bellis Inventions Expert our editorial process Mary Bellis Updated November 01, 2019 The refrigerator is such an important component of modern life that it is hard to imagine what the world was like without it. Before mechanical refrigeration systems were introduced, people had to cool their food using ice and snow, either found locally or brought down from the mountains. The first cellars for keeping food cold and fresh were holes that were dug into the ground and lined with wood or straw and packed with snow and ice. This was the only means of refrigeration throughout most of human history. Refrigeration The advent of modern refrigerators changed everything, eliminating the need for ice houses and other crude means of keeping food cool. How do the machines work? Refrigeration is the process of removing heat from an enclosed space, or from a substance, to lower its temperature. To cool foods, a refrigerator uses the evaporation of a liquid to absorb heat. The liquid or refrigerant evaporates at an extremely low temperature, creating cool temperatures inside the refrigerator. In more technical terms, a refrigerator produces cool temperatures by rapidly vaporizing a liquid through compression. The quickly expanding vapor requires kinetic energy and draws the energy it needs from the immediate area, which then loses energy and becomes cooler. Cooling generated by the rapid expansion of gases is the primary means of refrigeration today. Early Refrigerators The first known artificial form of refrigeration was demonstrated by William Cullen at the University of Glasgow in 1748. Cullen's invention, though ingenious, was not used for any practical purpose. In 1805, an American inventor, Oliver Evans, designed a blueprint for the first refrigeration machine. But it wasn’t until 1834 that the first practical refrigerating machine was built by?Jacob Perkins. The refrigerator created cool temperatures using a vapor compression cycle. Ten years later, an American physician named John Gorrie built a refrigerator based on Oliver Evans' design. Gorrie used the device to cool the air for his yellow fever patients. In 1876, German engineer Carl von Linden patented the process of liquefying gas that has become part of basic refrigeration technology. Improved refrigerator designs were later patented by African-American inventors Thomas Elkins?and?John Standard. The Modern Refrigerator Refrigerators from the late 1800s until 1929 used toxic gases such as ammonia, methyl chloride, and sulfur dioxide as refrigerants. This led to several fatal accidents in the 1920s, the result of methyl chloride leaking out of refrigerators. In response, three American corporations launched collaborative research to develop a less dangerous method of refrigeration, which led to the discovery of?Freon. In just a few years, compressor refrigerators using Freon would become the standard for almost all home kitchens. Only decades later would people realize that these chlorofluorocarbons endanger the ozone layer of the entire planet. As of 2018, compressor refrigerators were still the most common, though some countries have made efforts to phase out the use of chlorofluorocarbons. Some machines now use alternative refrigerants such as HFO-1234yf that are not as harmful to the atmosphere. There even exist refrigerators that operate using solar, magnetic, and acoustic energy.