W.G. Allinson, Y. Cinar, and P.R. Neal, Cooperative Research Centre for
Greenhouse Gas Technologies (CO2CRC) and The University of New South Wales; J.
Kaldi, CO2CRC and The University of Adelaide; and L. Paterson, CO2CRC and CSIRO
Earth Science and Resource Engineering
SPE Asia Pacific Oil and Gas Conference and Exhibition,
18-20 October 2010,
Brisbane, Queensland, Australia
This paper argues that any capacity estimation method requires a combination of
geological, engineering and economic analysis in order to provide rigorous
capacity estimates. It also argues that the classification of capacity
estimates should follow concepts in the existing SPE Petroleum Resource
Management System as closely as possible. The Energy & Environmental
Research Centre (EERC) (Gorecki et al., 2009) have developed a definition of
“practical storage capacity” that parallels the definition of petroleum
reserves as “the quantity of hydrocarbons which are anticipated to be
commercially recovered from known accumulation at a given date forward”, but
the EERC acknowledge that there is currently a problem with implementing a
price of carbon. This paper develops the economic analysis further than the
EERC. Like the EERC, we demonstrate that analytical and numerical injectivity
modelling based on geological models of the subsurface can help determine
practical storage capacity.
In doing this, the paper makes observations about methods for estimating
storage capacity, shows results of reservoir simulations and economic analyses,
draws on SPE and internationally accepted methodologies and definitions of
petroleum resources and discusses how equivalent definitions can be applied to
storage capacity. Finally, the paper provides recommendations for an improved
CO2 storage capacity classification system.
As the technology surrounding carbon capture and storage moves from research to
deployment, there is a need to estimate the amount of CO2 that can be safely
and securely stored in the subsurface. There is an ongoing discussion about
methods for determining CO2 storage capacity and an appropriate storage
capacity classification system.
Much of the literature on estimating the capacity of geological sites for
storing CO2 focuses on determining the total pore volume of a formation and
then applying “storage efficiency factor” to quantify the portion of this
resource that can be most likely accessed for storage. This paper identifies
the theoretical and practical pitfalls of such storage capacity estimation
methods and argues that the most appropriate means of producing rigorous
estimates of CO2 storage capacity is by a combination of geological, reservoir
engineering and economic analyses. Such an approach leads directly to
definitions of capacity that have direct correspondence with SPE definitions of
reserves and resources.
The aims of this paper are to —
(a) Discuss the difficulties in applying existing methods of determining CO2
storage capacity in the subsurface.
(b) Suggest an approach for determining CO2 storage capacity that involves
geo-science, engineering and economics.
(c) Illustrate this approach by applying it to different types of potential CO2
(d) Compare our illustrative results with the results obtained using other
(e) Suggest a CO2 storage capacity classification system that corresponds
closely to that used worldwide to classify petroleum resources.