Martin Neumaier, Ben Kurtenbach ArianeLogiX; Arnold Neumaier, University Vienna
We present a new asset evaluation workflow which enables fast and transparent screening of carbon storage assets, optionally constituting “hybrid assets”, i.e., a combination of CCS assets with standard oil and gas reservoirs. This workflow builds up on an existing asset evaluation software called Ariane, which will be extended to accommodate carbon storage evaluations in a similar manner. In the presented paper, we lay out our vision of how to extend the current methodologies and software so that transitioning geoscientists can perform the evaluation of CCS and hybrid oil & gas / CCS assets based on a solid understanding of pore space, fluid PVT properties, sealing dynamics, and other advanced geological processes.
As a starting point, we present an advanced methodology for oil and gas screening where one can derive fluid occurrence (oil or gas, or both), column heights and properties (densities, fluid ratios) from quantitative assumptions of charge and seal processes and PVT data. With only little modification, this oil and gas workflow can already be used for a static pore space-based assessment of injection volume prior to leakage through the top or fault seal, or structural spill.
For an advanced solution, future development of the methodology is proposed. First, dynamic injection needs to be modelled at human time scales, as well as the seal response. Also, alternative ways of capturing CO₂ such as water solution or mineral precipitation will need to be considered. Finally, the mixing of CO₂ with other fluids occupying the trap can complicate the simple approaches currently used.
The combined evaluation of oil and gas assets together with a carbon sequestration asset, and possibly other energy or resource assets, in a single workflow allows for the evaluation of “hybrid assets”. A very good example of a long term “fluids out – fluids in” pilot projects of such combined assets is the Sleipner Field offshore Norway. For a full quantitative evaluation of hybrid assets, the two (or more) parallel workflows and their calculations need to meet in a common denominator measuring value. This value is likely a combination of NPV (net present value), in any world monetary currency (USD, EUR, etc.), and total carbon footprint balance (in mega or giga tonnes), which ideally is negative.
In conclusion, implementing screening workflows for a diversity of assets into a single resource assessment system enables the combined evaluation of hybrid assets. All components of the hybrid assets are appraised and ranked for their combined economic value but also for carbon footprint. We think that many future energy assets will be of such a hybrid nature, both from an economic but also a social acceptance perspective. Setting up those hybrid assessments workflows, combining oil and gas, CCS and potentially other energy resources or subsurface storage opportunities, shall enable experienced staff from oil and gas companies to evolve into new technologies as required by the transition developing in the industry.