Definition of the word coal gas

The term "coal gas" originated in the early 19th century, as an outcome of the industrial revolution and the increasing demand for more efficient fuel sources. Coal, which had been used primarily for heating and cooking, was beginning to gain attention for its potential to produce a gas that could be used for lighting and power generation. Initially, coal gas was extracted accidentally during coal mining, as certain natural gases such as methane and carbon monoxide mixed with air in the coal seams. These gases were highly flammable and proved ideal for lighting purposes. However, producing coal gas on a commercial scale required a more controlled environment, which was achieved by heating coal in a retort, a device consisting of a closed chamber with air or steam introduced at one end. The resulting gas, known as gasworks gas, contained around 50% methane, along with CO, hydrogen, and other impurities. This was far more efficient than the previously used methods of lighting, such as candles or oil lamps, and revolutionized the way cities lit their streets. Today, the term coal gas is less commonly used, as natural gas has largely replaced it as a fuel source, due to its lower carbon footprint and higher efficiency. However, coal gas continues to have a significant role in certain industries, such as the production of certain chemicals, albeit in a more controlled and refined manner than in the past.