Wednesday, October 5, 2005
Carbon Capture and Storage (CCS) is a strategy to allow continued use of fossil fuels while reducing CO2 emissions. The IPCC has issued a special report on CCS -- the report essentially indicates that CCS may be a technically and economically feasible strategy to reduce CO2 emissions. But... the IPCC summary indicates that there are environmental and public health risks associated with the technology. Geological sequestration is being piloted; any threats appear to be from accidental release. Ocean sequestration is still in the experimental research stage; the potential risks to marine life may be substantial. One risk the IPCC has put to rest is the threat of sudden release from ocean sequestration -- stating there is no known mechanism for sudden release in the ocean. Yet the specter of 1800 people who died from a previously unknown mechanism that suddenly released lethal amounts of CO2 from Lake Nyos two decades ago haunts sequestration efforts.
Here is the summary for decision-makers. IPCC Carbon Capture and Storage Summary Full text of the IPCC special report should be available soon.
Some of the salient points covered in the Summary are:
CCS has the potential to reduce overall climate change mitigation costs and increase flexibility in achieving greenhouse gas emission reductions.
- The use of CCS for large-scale power plants (the potential application of major interest) still remains to be implemented
- CCS enables the control of the CO2 emissions from fossil fuel-based production of electricity or hydrogen, which in the longer term could reduce part of the dispersed CO2 emissions from transport and distributed energy supply systems.
- Most modelling as assessed in this report suggests that CCS systems begin to deploy at a significant level when CO2 prices begin to reach approximately 25 - 30 US$/tCO2.
- Available evidence suggests that worldwide, it is likely that there is a technical potential of at least about 2,000 GtCO2 (545 GtC) of storage capacity in geological formations. This is likely sufficient to cover the demand for geological storage over the century.
- Depending on the type of capture and storage, CCS would add 0.01 - 0.05 US$/kWh to the cost of electricity production.