Climate change mitigation by biomass gasification combined with CO2 capture and storage

Abstract

Biomass products can be used to generate electricity with only a low net emission of CO2. This is because the carbon is “recycled” via the atmosphere. Gasification technology combined with CO2 capture is being seriously considered in several countries for reducing CO2 emissions from power generation. It could also be applied to power generation from biomass; the net result would be to generate electricity with a net “negative emission” of CO2. In this chapter, the potential effectiveness of this approach is assessed in terms of cost, quantity of emissions avoided, and feasibility. The conclusion is that, despite the negative emissions of CO2, biomass gasification combined with CO2 capture and storage is likely to be less attractive than more established fossil fuel and biomass-based mitigation options. Biomass gasification with gas turbine combustion in an integrated cycle (BIGCC) combined with CO2 capture and storage is not a cheap option. This applies to both the cost of electricity generated, and the cost per ton of CO2 emission avoided. It is more expensive than a coal IGCC with CO2 capture, and more expensive than biomass use in BIGCC without CO2 capture. The extent of technology development required is significant to clean raw synthesis gas sufficiently to use in a shift-conversion catalyst, but it is possible that the technology could be used in a country that had a highly developed biomass energy industry and cheap biomass feedstock.