CO Capture and Storage - Energy and Climate: How to Achieve a Successful Energy Transition - page 105

8

CO 2 Capture and Storage

Stakes ahead

Fossil energy sources are still going to be used during the transition period.
Therefore, it will be necessary to deploy CO 2 capture and storage
(CCS) technologies on a large scale, especially with respect to the strong
impact upon the environment of coal-fired power plants.
Climate change requires urgent actions. Unfortunately, the decrease of
the share of fossil fuels in the world energy supplywill not be rapid enough
to reduce CO 2 emissions to the required level by 2050. For keeping the
right overall balance, it will be necessary to capture and store at least a
fraction of the CO 2 released by fossil fuels.
In order to avoid emitting into the atmosphere the CO 2 produced by
combustion, different means can be considered:

- Producing biomass through a process, fixing the

carbon and releasing oxygen into the atmosphere. Natural biomass
reservoirs are called carbon

photosynthesis

. In order to capture CO 2 and
reduce its content in the atmosphere, it is necessary to grow

sinks

addi-

quantities of biomass.
- Storing CO 2 deep underground: such a

tional

geological storage is the main

option considered presently.
- Storing CO 2 in oceans: the risks which might result from such ocean

storage (ocean acidification) are often considered too high to select

such an option.