“Carbon capture and storage can bridge the gap for the next
few decades, cutting emissions until we can shift to a low carbon economy”,
Professor Jacqueline McGlade EEA Executive Director said. “Our report shows
that while CCS may have an overall positive effect on air pollution, emissions
of some pollutants may increase. Understanding these types of trade-offs are
extremely important if we are to deploy this technology across Europe and the
world.”

CCS technologies require approximately 15 – 25 % more energy
depending on the particular type of technology used, so plants with CCS need
more fuel than conventional plants. This in turn can lead to increased ‘direct
emissions’ occurring from facilities where CCS is installed, and increased ‘indirect
emissions’ caused by the extraction and transport of the additional fuel.

The EEA report identifies some of the potential benefits and
trade-offs for the main air pollutants. It also presents a life-cycle case
study for 2050 considering three different scenarios, showing the potential
impacts on emissions of air pollutants if CCS were widely implemented in
Europe. Key findings include:

• Sulphur
  dioxide (SO₂) emissions from power plants are predicted to fall
  when carbon dioxide (CO₂) is captured, as SO₂ must also
  be removed after the fuel combustion stage for technical reasons. Although the extraction
  and transportation of additional coal will lead to higher SO₂
  emissions from these stages of the CCS life-cycle, SO₂ emissions
  should decrease overall.
• Particulate
  matter (PM) and nitrogen oxide (NO_x)
  emissions are expected to increase in line with the amount of the additional
  fuel consumed if no additional measures to reduce emissions are installed.
• Ammonia
  (NH₃) is the only pollutant for which a significant increase in
  emissions is expected to occur, with emissions potentially increasing by a factor
  of 3 or more. The foreseen increase is due to the degradation of the
  amine-based solvents used to capture the CO₂. However, in absolute
  terms the increase is small compared to existing ammonia emissions in Europe,
  94% of which comes from agriculture. Ammonia contributes to acidification and
  eutrophication of the environment and also can form harmful fine particulate
  matter when released in the atmosphere.  
• Potential carbon
  dioxide (CO₂) savings from CCS vary greatly across the three
  scenarios in the report. Emissions of CO₂ in the EU would fall by around
  60 % by 2050 if CCS were implemented at all coal-based power generation plants.
  Implementing CCS at all coal, gas and biomass plants would result in net
  negative emissions – in effect removing CO₂ from the atmosphere.
  This assumes that all biomass is harvested sustainably without any net changes
  to the carbon stock.
• The case study also shows clearly that the extraction
  and transport of additional coal can contribute significantly to the life-cycle
  emissions for coal-based CO₂ capture technologies.  Overall, however, CCS is considered to be
  generally beneficial both in terms of climate change and air pollution. However,
  the potential increase in certain pollutants such as NH₃, NO_x
  and PM is important.

Carbon capture and storage
technologies are assumed to play a central role in helping Europe achieve its
long-term GHG reduction objectives in a cost-effective way, reducing domestic
GHG emissions by 80-95 % by 2050. Implementing CCS is therefore
considered as a bridging technology, and should not introduce barriers or
delays to the EU’s objectives of moving toward a lower-energy and
more resource-efficient economy.

In the EU, there are plans to
build several demonstration plants for CO₂ capture and storage in
order to commercialise the technology from 2020. Currently, there are around 80
large scale CCS projects at various stages of development around the world but
only a few are operational. There are as yet no large-scale CCS plants in operation
which cover all three elements of the CCS chain – the capture, transport and
storage of CO₂.