Trends of fluidized bed boiler industry to meet the requirements of future power generation

The age profile of the existing power plants results in a high demand for new power production capacity within the next years. The replacement or the modernisation of the old power plants utilising modern technology with high steam parameters and high efficiencies would contribute to the saving of the resources and to the reduction of all kind of emissions. The new investments must be able to compete decades forward in order to secure competitive power production. CFB combustor with high fuel and operational flexibility including wide range of coals would give an extra opportunity for the operators to improve competitiveness in power generation business. Currently circulating Fluidized Bed (CFB) boilers with conventional design have been successfully demonstrated at the < 300 MWe scale. The net efficiency of those plant designs are on level of 38-40% depending on fuel and condenser conditions. During the past years, the once through supercritical (OTSC) CFB technology has been developed and readiness to propose commercial projects at medium scale < 500 MWe has been created. The CFB technology has many advantages also in utility scale (fuel and operational flexibility, multifuel capability, low emissions, in-situ sulphur reduction, etc), that would fulfil the requirements of utility operators at deregulated energy markets. In addition the foreseen need for new power production capacity which should first compensate the retirement of the older units and second cover the forecasted increase in electricity demand will require new clean coal technologies to secure coal competitiveness and improve acceptance of coal utilisation in power production. New plants with supercritical steam parameters can now achieve overall net efficiencies in the 43-45% range but even higher efficiency, up to 50%, is achievable due to development of new superheater materials.