Biomass-fired cogeneration systems with CO2 capture and storage

In this study, we estimate and analyze the CO2 mitigation costs of large-scale biomass-fired cogeneration technologies with CO2 capture and storage. The CO2 mitigation cost indicates the minimum economic incentive required (e.g. in the form of a carbon tax) to make the cost of a less carbon intensive system equal to the cost of a reference system. If carbon (as CO2) is captured from biomass-fired energy systems, the systems could in principle be negative CO2 emitting energy systems. CO2 capture and storage from energy systems however, leads to reduced energy efficiency, higher investment costs, and increased costs of end products compared with energy systems in which CO2 is vented. Here, we have analyzed biomass-fired cogeneration plants based on steam turbine technology (CHP-BST) and integrated gasification combined cycle technology (CHP-BIGCC). Three different scales were considered to analyze the scale effects. Logging residues was assumed as biomass feedstock. Two methods were used to estimate and compare the CO2 mitigation cost. In the first method, the cogenerated power was credited based on avoided power production in stand-alone plants and in the second method the same reference output was produced from all systems. Biomass-fired CHP-BIGCC with CO2 capture and storage was found very energy and emission efficient and cost competitive compared with other conversion systems.