The power of a boiler may be defined as

• A. the ratio of heat actually used in producing the steam to the heat liberated in the furnace
• B. the amount of water evaporated or steam produced in kg per kg of fuel burnt
• C. the amount of water evaporated from and at 100 C into dry and saturated steam
• D. the evaporation of 15.653 kg of water per hour from and at 100 C