Following the Kyoto Protocol, the EU is committed to a reduction of 8%
in greenhouse gas emissions in the implementation period 2008-2012. One way of reducing CO2 emissions
is to capture CO2 from industrial point-sources and store it underground.
Approximately one-third of anthropogenic emissions arise from transport, one-third from industrial
and domestic sources and one-third from power generation. While achieving substantial reductions in emissions
from either of the first two will be a long-term process, the technology to capture CO2 from power plant is
already available and could lead quickly to significant reductions in emissions —provided mechanisms are
available to dispose of the CO2 thus captured. The capture and underground storage of industrial quantities
of carbon dioxide is currently being demonstrated at the Sleipner West
gas field in the Norwegian sector of the North Sea. It has been suggested that
such geological sequestration could offer potential long-term storage of significant
quantities of CO2 that would otherwise be emitted to the atmosphere.
However, if geological sequestration of CO2 is to become acceptable, certain key issues
must be addressed. These include the long-term safety and stability of storage underground and the potential
effects of leakage from an underground storage reservoir. Natural CO2 fields, and places where CO2 is
actively migrating from underground to the Earth's surface, are widespread in Europe and elsewhere in the
world. These are direct natural analogues for the geological storage (and leakage) of anthropogenic CO2.
They therefore provide natural laboratories in which to address key issues for geological sequestration.
EU policies are focussed on sustainable energy production and afforestation but can these
achieve necessary reductions? The EU TERES report estimated the overall potential renewable energy to be over
200 million tonnes of oil equivalent of final energy consumption for the 12 member states. It is predicted
that changing energy production practices (switching to natural gas and nuclear energy from coal and oil)
and increased efficiency in the transport sectors will contribute significantly to the EU's target reduction
for the Kyoto protocol. Nevertheless, by 2010 renewable energy is only expected to represent 15% of all
primary energy use. Within the EU there are still significant reserves of fossil fuels (some 200 years
supply of coal, 50 years supply of natural gas). Further, Kyoto is widely recognised as only the first
step towards achieving the necessary large-scale reductions in GHG emissions. Other mechanisms are therefore
proposed that involve different sinks for the emitted CO2. Sleipner and Weyburn indicate that underground
sequestration can be a cost-effective measure on the short-term. Do we know it is a viable option in the
medium to long term?