The term “waste to energy” has traditionally referred to the practice of incineration of garbage. Today, a new generation of waste-to-energy technologies is emerging which hold the potential to create renewable energy from waste matter, including municipal solid waste, industrial waste, agricultural waste, and waste byproducts. The main categories of waste-to-energy technologies are physical technologies, which process waste to make it more useful as fuel; thermal technologies, which can yield heat, fuel oil, or syngas from both organic and inorganic wastes; and biological technologies, in which bacterial fermentation is used to digest organic wastes to yield fuel.
Waste-to-energy technologies convert waste matter into various forms of fuel that can be used to supply energy. Waste feedstocks can include municipal solid waste (MSW); construction and
demolition (C&D) debris; agricultural waste, such as crop silage and livestock manure; industrial waste from coal mining, lumber mills, or other facilities; and even the gases that are naturally
produced within landfills. Energy can be derived from waste that has been treated and pressed into solid fuel, waste that has been converted into biogas or syngas, or heat and steam from
waste that has been incinerated. Waste-to-energy technologies that produce fuels are referred to as waste-to-fuel technologies.
Advanced waste-to-energy technologies can be used to produce biogas (methane and carbon dioxide), syngas (hydrogen and carbon monoxide), liquid biofuels (ethanol and biodiesel), or
pure hydrogen; these fuels can then be converted into electricity. The primary categories of technology used for waste-to-energy conversion are physical methods, thermal methods, and biological methods.
