Comparison of concepts for thermal biomass utilization, with the example of the Netherlands

Biomass and waste, which are the focus of the activities at the section Thermal Power Engineering of the TU Delft, are the most important renewable energies today. They will maintain their role in the future. There are different possibilities to convert biomass and waste to power and heat. The combustion of biomass can be considered state-of-the-art technology and plants ranging in capacity from a few kW up to several MW are available on the market. The selection of the combustion technology is dependent on the scale and the kind of biomass. Power can be produced by means of a steam turbine, which is attractive in units above 1 MW. Gasification, in contrast, is a technology that could not yet find a wide use. But, in combination with gas engines, gas turbines or fuel cell, gasification has the advantage of a high electrical efficiency. Direct co-combustion of biomass in coal-fired steam power plants is the most economic choice and it is widely applied in the Netherlands. By an additional pyrolysis or gasification step, it is possible to separately remove and utilize the ashes of coal and biomass, and expected operational problems, such as corrosion, can possibly be avoided.