Waste incineration has been around for a long time. From the time that humans first discovered fire, people have tended to burn what was not needed. During the 20th century, people began to understand that they could in effect kill two birds with one stone. People could rely on waste incineration as a means of disposing of refuse they did not need, rather than creating larger landfills, and they could also use the process of incineration itself to create energy.