Achieving Negative Emissions with the Most Promising Business Case for Bio-CCS in Power and CHP Production

Abstract

The urgency for significant reductions in global greenhouse gas (GHG) emissions highlights the importance of carbon sinks, i.e. solutions that can remove CO2 from the atmosphere, and the possibility for offsetting historical emissions. The later the global GHG emissions turn to decline, the greater is the need for sinks or so called “negative emissions”. Achieving negative CO2 emissions is possible by applying carbon capture in processes using biomass as feedstock (bio-CCS).Electricity production efficiency of chemical looping combustion (CLC) power plant is higher than in power plants based on solid fuel and other CO2 capture technologies. The higher efficiency of CLC in comparison to other CCS technologies emphasizes the cost benefit of bio-CLC in terms of both, merit order and overall economic feasibility. The advantage of combined heat and power production (CHP) over the sole power production has been recognised also in the case of CCS applications. By CHP, process efficiencies over 90% (on LHV basis) are possible and efficiency penalties of the CCS processes can be minimised as decreased efficiency in power production can be compensated by additional heat production.In this paper, the most feasible concept for bio-CCS in power and CHP production is presented based on improved efficiency, negative emissions and benefits of CHP within Nordic bioenergy context. Techno-economic analyses of industrial scale CLC power plant and CHP plant are presented in different market situations. Feasibility of CLC investment and the utilization of such plants are investigated and compared to oxy-fuel and air combustion references in a fictive energy system. In general, the smaller scale is often limiting biomass applications, CLC, CHP and utilisation of CO2. In the presented bio-CLC concept, all of these advantages are combined in a scale which is realistic for commercial application.