Question: When did coal become a major energy source?

Disambiguated questions and answers:
context: The history of coal mining goes back thousands of years. It became important in the Industrial Revolution of the 19th and 20th centuries, when it was primarily used to power steam engines, heat buildings and generate electricity. Coal mining continues as an important economic activity today. Compared to wood fuels, coal yields a higher amount of energy per mass and can often be obtained in areas where wood is not readily available. Though it was used historically as a domestic fuel, coal is now used mostly in industry, especially in smelting and alloy production as well as electricity generation. Large-scale coal mining developed during the Industrial Revolution, and coal provided the main source of primary energy for industry and transportation in industrial areas from the 18th century to the 1950s. Coal remains an important energy source because of its low cost and abundance compared to other fuels, particularly for electricity generation. Coal is also mined today on a large scale by open pit methods wherever the coal strata strike the surface or are relatively shallow. Britain developed the main techniques of underground coal mining from the late 18th century onward, with further progress being driven by 19th century and early 20th century progress. However, oil and gas were increasingly used as alternatives from the 1860s onward.
question: During what time period did coal become a major energy source globally?
short_answers: Industrial Revolution

19th and 20th centuries
wikipage: History of coal mining

context: The history of coal mining goes back thousands of years. It became important in the Industrial Revolution of the 19th and 20th centuries, when it was primarily used to power steam engines, heat buildings and generate electricity. Coal mining continues as an important economic activity today. Compared to wood fuels, coal yields a higher amount of energy per mass and can often be obtained in areas where wood is not readily available. Though it was used historically as a domestic fuel, coal is now used mostly in industry, especially in smelting and alloy production as well as electricity generation. Large-scale coal mining developed during the Industrial Revolution, and coal provided the main source of primary energy for industry and transportation in industrial areas from the 18th century to the 1950s. Coal remains an important energy source because of its low cost and abundance compared to other fuels, particularly for electricity generation. Coal is also mined today on a large scale by open pit methods wherever the coal strata strike the surface or are relatively shallow. Britain developed the main techniques of underground coal mining from the late 18th century onward, with further progress being driven by 19th century and early 20th century progress. However, oil and gas were increasingly used as alternatives from the 1860s onward.
question: When did coal first start to become a major energy source?
short_answers: 18th century
wikipage: History of coal mining

Long answers:
long_answer: Coal became a major energy source globally during the time period of the 19th and 20th centuries, while it first started to become a major energy source in the 18th century.