What is the energy content of heavy fuel oil?

Heavy fuel oil (HFO) is a type of residual fuel oil that is typically used in ships, boilers, and other large industrial equipment. It is made up of heavier hydrocarbons that remain after the lighter components of crude oil have been distilled off. The energy content of HFO varies depending on its composition, but it typically ranges from 9,500 to 10,500 British thermal units (Btu) per pound. This means that HFO has a lower energy content than some other fuels, such as diesel fuel or natural gas, but it is still a relatively efficient fuel source.