What is a common source of fuel for boilers?

Natural gas, oil, or coal are indeed common sources of fuel for boilers, primarily due to their historical usage and availability in various industrial applications. These fuels are preferred because they enable efficient combustion, which is essential for generating the steam or hot water needed in heating systems and power generation.

Natural gas is particularly favored in many applications due to its clean-burning properties, resulting in lower emissions compared to other fossil fuels. Oil has historically been used in many heating systems, particularly where natural gas may not be readily accessible. Coal, while less common in recent developments due to environmental concerns, still plays a significant role in certain industries that require high-temperature processes.

The other sources listed, such as electricity, solar, and biodiesel, while they can be used in specific applications, do not have the same widespread utility as the traditional fuels. Similarly, propane, wood, and ethanol might serve as alternative fuels but are not as predominant in traditional boiler operation. Wind, geothermal, and hydrogen represent more advanced or emerging technologies that may not yet be widely implemented in conventional boiler applications, making them less common sources of fuel at this time.