The negatives of Carbon Capture and Storage

The negatives of Carbon Capture and Storage

Earlier this months Aberdeenshire Council approved the construction of a Carbon Capture and Storage facility at Peterhead. one of the first of its kind. This facility will pump millions of tonnes of CO2 back into depleted gas wells in the North Sea. There was little protest, with many praising the project’s potential to create jobs in the area and reduce CO2 emissions. Leader of the SNP Nicola Sturgeon said it was a “big opportunity for Scotland”. There was however, little discussion about the potential negative effects of such a project and little debate as to whether encouraging continued use of fossil fuels is really a sustainable approach.

Plants fitted with Carbon Capture and Storage (CCS) capabilities require 15-25% more energy than conventional plants. This additional energy use can increase emissions indirectly, such as emissions caused by the extraction and transportation of this additional fuel. The technology used in CCS can also increase certain aspects of air pollution. Particulate matter and Nitrogen Oxide are both predicted to increase due to the additional fuel consumption. Ammonia is expected to increase by more than 3 times current levels from energy plants, due to the degradation of the solvents in the process of capturing Carbon. Ammonia can lead to acidification and Eutrophication as well as forming particular matter in the atmosphere. Particulate matter is considered by the World Health Organisation to be the deadliest form of air pollution due to its ability to enter the respiratory system. Some of the potential effects can include DNA mutations (which can lead to cancer), heart attacks, respiratory illness and premature death. The overall increase in Ammonia is likely to be small overall as the agricultural sector is by far the biggest emitter, however it is still important to consider these consequences when there are safer alternatives available.

CCS has also been linked with damaging the environment due to leakage of CO2 from the pipelines or storage reservoir. Leakage of CO2 underground has been shown to increase plant mortality, reduce growth and create potentially severe localised damage to ecosystems. The mining and transport of the additional fuel needed for CCS, usually Coal, produces its own environmental damages as well as the environmental cost of building such a plant and all of the required pipelines. Gradual leakage of CO2 or large scale leakage caused by catastrophic failure of the system could remove the benefits of capturing CO2 as well as producing additional environmental damage and damage to human health. The CO2 would need to remain stored for 100s of years or potentially indefinitely and the feasibility of this has been questioned. The built up of pressure underground may also lead to small seismic events.

Some have claimed that the environmental risks and risks to human health involved in CCS are similar to those already experienced in the oil and gas industry. But is that really acceptable? Surely we should be considering solutions that do less damage, not a similar amount.

The nightmare scenario associated with Carbon Capture and Storage is the threat of sudden catastrophic leakage of CO2, which would decimate human and animal life in the surrounding area. A good example of this is the sudden release of CO2 from Lake Nyos in 1986. This resulted in the deaths of 1700 people in rural Cameroon. Nuclear power has long been frowned upon despite having no direct carbon emissions because of the nightmare scenarios associated with it, so these events are worth considering. This situation is of course, unlikely, however this technology is new and untested and it needs to endure for extremely long timescales, which is a challenge unlike any Humans have faced before.

A more likely scenario is gradual leakage of CO2. This could occur if the incorrect site is selected or the site is not prepared correctly. Leakage of CO2 would remove the purpose of Carbon Capture and Storage and may also pose a risk to fresh groundwater resources if the site is incorrectly selected. Aquifers that are not connected with groundwater systems have been proposed as potential site for CCS. However it has also been argued that injecting CO2 into these aquifers can cause acidification of the water, increasing its ability to break down the surrounding rocks, increasing the potential for leakage into the soils or water table. Considering the fact the CO2 would have to be stored for 100s or 1000s of years, we cannot be certain what would happen.

Overall CCS carries a host of risks and unanswered questions, so needs to be carefully regulated and scrutinised. CCS may be useful in carefully selected sites however it is important it is not viewed as a panacea, as it doesn’t address the core problem of fossil fuel usage, it simply masks the main problem associated with it, which is carbon emissions. There are ways to reduce emissions which carry none of these risks and will be required when fossil fuels run out anyway, so is it really worth taking all of these risks for a technology which requires further use of fossil fuels, distracts from the adoption of renewable energy and doesn’t address the core issue of unsustainable fossil fuel dependence?