Simple Grate	Chain Grate	Reciprocating Grate
Fuel feeding	Manual	Using a chain conveyor to furnace	Automatically using a conveyor system
Ash Disposal	Mostly manually	The ash gets disposed from end of grate automatically using the chain	The ash is disposed automatically from grate end by the movement of grate
Mechanism	Fixed grate with a passage for ash to fall to pit	Furnace where the fuel travels using a chain	Grate which keeps moving shifting the fuel from one to another.
Efficiency	Lowest	Mid Level	Highly Efficient
Fuel types	Low Moisture fuels like oil, natural gas, LDO , Coal and dried wood logs	Solid Fuel with uniform sizes such as coal, biomass, wood chips and rice husk	Higher range of fuels including agricultural and municipal waste as well.

Thus, a boiler must be chosen based on fuel availability , space and nature of operations.