Application to UK Case Studies

The methodology has been applied to assess the techno-economics of several combinations of carbon-dioxide source capture technology and storage reservoir. The number of parameters that can influence scheme techno-economics mean that it is only possible to present overview data here. For detailed assessment of particular combinations of technology and storage reservoir, it is suggested that the reader uses the model, which can be made available on request.

4.7.1 Assumptions

The techno-economic results are dependent on the unit costs of several consumables and products. For the indicative results described here, the costs in table XXX are assumed. All other consumables and products are assumed to have no value associated with them. To calculate carbon abatement costs, comparison has been made with the cost and CO2 emissions of supplied electricity, taken to be equal to UK

grid supply averages.

Quantity Assumed value

Coal cost Gas cost

Supplied electricity cost

4.7.2 Case studies

The case studies considered comprised permutations of power station location, power station type and storage location. The combinations of power station location and storage location considered are shown in table XXX.

Power station location Storage reservoir

Midlands (Ratcliffe on Soar)

4.7.3 Results

The ranges of costs of carbon dioxide avoidance for each of the power station technologies is shown in table XXX. It should be noted that the ranges reflect the effect of the variations in the case studies, rather than uncertainties in the input data,

Power plant Carbon avoidance costs

PFFGD + MEA

IGCC CCGT

4.8 Conclusions

4.8.1 Achievements

The major outcomes from this work are as follows:

• A whole system cost model for the implementation of CCS plant in the UK has been developed and demonstrated.

• The model has been used to investigate the techno-economics of building CCS systems in the UK, as a function of plant type and geography. Some consideration was also given to the impact of energy supply scenarios. However as the model has been formulated only for single source to single sink analysis, this was not treated in detail in the current work.

• The extent of the study was largely limited by poor data availability on the capital cost of carbon dioxide capture plant as a function of the overall technical parameters. For techno-economic assessment purposes, a detailed parameter of the costs of capture equipment would be of great values. This however would only be practical with significant industry involvement and issues of commercial confidentiality would need to be tackled.

• Due to the data uncertainties, the developed modelling framework and computer code are the primary outputs from the study. The capabilities of the model significantly exceed the validity of the input data available from the open literature. Thus the model, and its underlying methodology provide a

basis for future studies of CCS in the UK as more reliable data becomes available.

• A GIS for the techno-economic investigation of candidate pipeline routes from carbon dioxide sources to offshore pipeline landing points has been developed. The GIS has been used to investigate the impact of routing constrains, and in particular environmental impact considerations, on the relative pipeline construction cost.

4.8.2 Recommendations for further work

The work described has fulfilled the objectives set out in the original proposal. A major difficulty encountered, which was not fully anticipated at the outset, was the poor availability of cost data for components. The data availability, rather than the capabilities of the developed model, has constrained the study and thus the main suggestions for further work are oriented around the collation of better input data. Specific recommendations are as follows:

• The key recommendation from this work is that the scope for assessment and overall design optimisation of CCS systems is severely limited by the

availability of cost data in the open literature. There is an urgent need for collation of cost data associated with the fossil fuel supply chain. It is unlikely that reliable decisions regarding the viability of CCS in the UK can be taken until such data is collated.

• The issue of monitoring of storage sites needs to be considered in more detail. In particular a detailed model for the cost of monitoring, which is currently almost impossible to predict, should be developed. Although not discussed substantially on the main text there is considerable debate in the community over the extent of the monitoring required and the linked question of the time period over which it is desirable that carbon dioxide is retained in storage reservoirs. These questions can only be answered through an economically oriented risk analysis, which in turn requires a cost model for the monitoring processes.

• There is a need for design guidance on the construction and routing of CCS pipelines. Existing UK guidance, perhaps unsurprisingly, makes no reference to the construction of long pipelines carrying supercritical carbon dioxide.

4.9 References

Center for Energy and Environmental Studies, Carnegie Mellon University, Integrated Environmental Control, http://www.icem-online.com, Pittsburgh PA (2005)

Chapter 5