Prospects for producing low carbon transportation fuels from captured CO2 in a climate constrained world

Abstract

Abstract The climate implications of technologies that capture CO 2 to produce transportation fuels (CCTF) are investigated by studying two examples: Biodiesel from microalgae and Sandia National Laboratory’s S2P process. Simple performance and economic models for each technology are examined in the context of a bifurcated–“pre-CCS” vs. “post-CCS”–climate regime in which CCTF uses CO 2 that is, respectively, captured from power plant flue gases or taken from CCS pipelines. CCTF promises to improve domestic energy security by converting sunlight and waste CO 2 into transportation fuels; in addition, these fuels are roughly climate neutral when CO 2 is captured from either flue gases or directly from the atmosphere. However, after the power sector becomes largely decarbonized under a stringent climate policy, large point sources of concentrated CO 2 are likely to be relatively rare, and unfortunately, fuels made from pipeline CO 2 destined for storage do not have markedly reduced net GHG emissions. Thus, absent the development of economical CO 2 capture from air, it’s difficult to see how CCTF can play a significant long term role in decarbonizing the US transportation sector (and thus reaching US climate goals).