This paper aims to compare fuel alternatives to a boiler used for steam generation. Among the options compatible with the boiler model used by the company, the fuel options were firewood of Acacia decurrens, Eucalyptus globulus, Pinus taeda or Pinus elliottii and dry biomass. There was the cost versus calorific value of the alternatives found, and the wood of Acacia decurrens is the fuel that has the lowest price.