Guy Allinson

CO2 Geological Storage Economics

Publisher Summary This chapter illustrates the effects of uncertainties involved in estimating the costs of storing CO2. The analyses show that the costs are particularly sensitive to parameters such as the CO2 flow rate, the physical properties of the underground reservoir, and the market prices of equipment and services. Therefore, variations in any one of these inputs can lead to significant variation in the costs of CO2 storage. When one allows for reasonable variations in all the inputs together in a Monte Carlo simulation, a large range of total CO2 storage costs is possible. This chapter also analyzes the impact of storing other gases together with CO2. The other gases include methane, hydrogen sulphide, nitrogen, nitrous oxides, and oxides of sulphur, all of which could be captured together with CO2 depending on the source and the relative economics of capture and storage. Allowing these other gases in the CO2 stream requires higher compression power and/or a larger diameter pipeline and more and/or larger diameter wells etc. We show the effect on storage costs when varying quantities of other gases are injected with the CO2.

The economics of CO2 and mixed gas geosequestration from stationary greenhouse gas emitters

Publisher Summary This chapter illustrates that greenhouse gas emission sources produce mixed gases. It analyzes the cost of separating a gas mixture from a power station flue gas stream followed by offshore sub-surface storage. It also examines the use of gas membrane separation as well as chemical absorption to achieve varying concentrations of CO 2 , in the gas mixtures sequestered. The results indicate that, using a gas membrane separation system, the lowest sequestration cost per ton of CO 2 avoided occurs when a mixed gas with a CO 2 content of about 60% is sequestered. Lower costs and higher tonnages of CO 2 avoided can be achieved using an amine based absorption separation system. The results also confirm that at the lowest cost point, and over most of the range of cases studied, the cost of separation is significantly greater than the cost of storage. However, this would depend on the source of the CO 2 , the distance between the source and the injection site, and, the reservoir into which CO 2 is injected.