Details

Autor(en) / Beteiligte

• Bennett, Simon J.
• Schroeder, David J.
• McCoy, Sean T.

Titel

Towards a Framework for Discussing and Assessing CO2 Utilisation in a Climate Context

Ist Teil von

• Energy procedia, 2014, Vol.63, p.7976-7992

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2014

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• This paper aims to place discussions about CO2 utilisation onto a more secure foundation from the perspective of climate change mitigation. A conceptual framework is proposed that comprises three criteria for evaluating CO2 utilisation options from the viewpoint of emission reduction potential. This framework places life cycle analysis at its forefront. Examples of emissions benefits for thermodynamic minimum energy inputs and possible real-world conditions are used to show that not all CO2 utilisation is equally beneficial from a climate perspective. Most current and potential uses of CO2 do not appear to yet satisfy the three main criteria of emission reduction benefits, revenue to cover CO2 feedstock costs and meaningful scale. The notable exceptions are certain (geographically limited) approaches to enhanced oil recovery (CO2-EOR). Due to the energy required to convert CO2 to useful products it appears highly likely that reducing CO2 emissions through CO2 utilisation will only be possible if the electricity (and, in some cases, the thermal energy) inputs are from renewable sources. This raises questions about the most appropriate use of renewable resources, especially if they are to be employed for the purpose of partially mitigating emissions from large stationary fossil fuel combustion plants. It also raises questions about how to match the potential revenue from and scale of CO2 utilisation based on variable renewable resources with investments in CO2 capture at meaningful scales. CO2 utilisation options that can proceed without a CO2 capture and purification step or can be located in regions where CCS is an ongoing commercial business may offer good opportunities for further development if they can scale to multi-million tonne per year activities. Climate policies that aim to support revenues for CO2 utilisation activities will need to carefully consider how the fossil fuel value chain allocates liability for environmental damages associated with life cycle emissions; these are likely to be greater than zero but not accurately predictable.