CO2 capture, transport and storage, also referred to as CCS, may well play an important role in reducing emissions of the greenhouse gas CO2, however, it should not be viewed as the answer to all environmental problems. CCS can actually contribute to other environmental problems, depending on the technology used. These are some of the conclusions of the PhD research conducted by Joris Koornneef at Utrecht University. His dissertation describes the effects of CCS on the environment, health and safety. Koornneef will defend his PhD research on 17 May.
It has been established with a high degree of certainty that greenhouse gas emissions from human activities are the cause of climate change. To limit this effect, emissions of greenhouse gases, including CO2, must be kept to a minimum wherever possible. One tool to achieve this is CCS, which entails the capture of greenhouse gases at sources such as power stations, followed by the compression, transport and underground storage of the gasses. “Before CCS can be carried out on a large scale, it must be clear how it will effect the environment, public health and safety” asserts Koornneef, whose research included an analysis of the total environmental impact of CCS and the risks of transporting CO2 by pipeline.
Total environmental impact of CCS
As part of the life-cycle analysis, Koornneef assessed the environmental impact of the entire chain for coal fired power stations involving CCS – from the coal mine to the generation of electricity. He then looked at the impact on various environmental problems. “CCS substantially reduces the contribution to the greenhouse effect”, says Koornneef. “CCS can also be beneficial at a more localised level, by significantly reducing emissions of fine particulate matter and sulphur dioxide, for example. However, additional energy is required for the capture, transport and storage of CO2.” Koornneef demonstrates that the use of post-combustion - a particular method of CO2 capture - at coal fired power stations, will lead to increased acidification and nitrogen pollution. It also contributes to other environmental problems, such as resource depletion and the destruction of the ozone layer. Selecting the right technology and improving existing technology will greatly affect the total environmental impact of CCS.
CO2 transport by pipeline
Koornneef also studied the uncertain factors in the risk analysis of CO2 transport by pipeline. This is an important aspect in the public debate on the safety of CO2 storage near Barendrecht in the Netherlands. According to Koornneef, the existing models have not been tested for high pressure CO2 release and dispersion. “However, that’s not to say that CO2 pipelines are unsafe. It looks as if the risks can be mitigated quite effectively with current technology, such as safety valves”, says Koornneef.
CO2 capture risk studies
Finally, Koornneef also researched the risk studies associated with CO2 storage projects, concluding that accurate calculation of the risks is not currently possible. However, this does not mean that we lack the knowledge to assess whether underground storage can be performed safely. Koornneef believes it is highly unlikely that CO2 will escape and have negative effects on the environment or public health. Nonetheless, it is important that storage projects be monitored in order to establish more precisely how CO2 behaves when stored underground, for instance.
This study was conducted within the context of the Dutch research programme CATO (which stands for CO2 capture, transport and storage), which took place from 2005 to 2009. Funded partly by the government, this research programme was a consortium of businesses, universities (including Utrecht University), research institutes and interest groups. In 2009, the research was continued with the launch of the CATO-2 programme.
PhD viva
Joris Koornneef will defend his dissertation on 17 May 2010 at 12.45 p.m. in University Hall (Academiegebouw) at Domplein 29 in Utrecht. Dissertation: ‘Shifting streams- on the health, safety and environmental impacts of carbon dioxide capture, transport and storage’, ISBN 978-90-8891-163-7. Supervisors: Prof André Faaij and Prof Wim Turkenburg, co-supervisor: Andrea Ramírez Ramírez.
Further information
Peter van der Wilt, Utrecht University press officer, +31 (0)30 253 3705, p.m.vanderwilt@uu.nl.
About CATO: http://www.co2-cato.nl