General knowledge of roasting of coffee beans electrothermal baking technology

Electricity was only used to drive the rollers of traditional drum dryers and blowers and cooling fans at the end of the 19th century, but it was not an effective source of heat for large-scale baking at that time. Any chef knows that the rate at which electricity is converted into heat is much lower than that at which gas is converted into heat; in addition, the price of gas is much cheaper than electricity. Just from here.