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Results by Cases
In this chapter, the results of the costing exercise are presented. All costs are reported in €/tonne CO2 stored.
5.1
Cost overview totals
For each case, the cost model was first run with the input cost elements set to their base (most likely) values, according to the case. The resulting costs correspond to what has been termed the “Medium” scenario. The model was then run to determine the three major uncorrelated drivers that had the largest impact on cost – field capacity, well capacity (injectivity times the life of the well) and liability. Note that other cost items related to well capacity sometimes have a large impact on cost (e.g. well completion cost), but these are related to the well capacity driver. Liability, however, is completely decoupled from other items and has a large impact on Low cost scenarios. The Low and High cost scenarios were then obtained as follows: for each case, the model was run with these three major drivers set to their minimum values for the Low cost scenarios and maximum values for the High cost scenarios, whilst taking care of their combined effects. This method has the advantage over mathematically more rigorous techniques (e.g. Monte Carlo techniques) in that the Low and High scenarios correspond to a transparent set of input cost elements, while still representing realistic (i.e. reasonably probable) Low and High scenarios.
Figure 5: Storage cost per case, with uncertainty ranges – triangles correspond to base assumptions The resulting total storage costs are presented in Figure 5, with the CAPEX/OPEX split in Table 4. A key conclusion is that within each case there is a wide cost range, the High cost scenario being three to up to 10 times more expensive than the Low cost scenario. This is mainly due to natural variability between storage
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