Burning the land and boiling the sea

Recently it was announced that licenses have been granted for underground coal gasification projects in the Firth of Forth along with 15 others in the UK.

The laws surrounding both are different due to the Scottish Government having their own environmental policies. Essentially the Scottish Government have prevented “fracking” on the basis of it being still under assesment. UCG is the conversion of coal to syngas whereas fracking is the release of gas underground and so the processes are often confused. I myself have gotten this wrong on a previous edition of this post, but I have since spoken to an expert and will try and set the record straight.

Fracking involves pumping fluid into the ground and forcing the gas upwards. UCG involves drilling into a coal seam, injecting gases and a partial combustion (gasification), before extracting the gas produced. Figure 1 illustrates the concept in more detail. The gas will most likely be used as a petrochemical feedstock.

How UCG works, if it works.

The possible problems are numerous with campaigners quick to point them out. With the combustion process reaching over 1500°C the effect on the water and rocks could be serious and subsidence is a worry for residents. However recent evidence suggests that the heat poses no environmental threat and that subsidence will only occur in the seabed to a very small amount. Secondly, the process can be highly polluting and in some cases projects have suffered leaks and pollution problems. The areas of sea where the projects are proposed all are home to UK fish and mammal species, all of which would be negatively affected if this happened. The Scottish WWF are branding the scheme “irresponsible and a complete non-starter”. If done correctly however the project is expected to be much less polluting than conventional coal burning and so the pollution aspect of this project is dependant on the precision of those involved rather than on chemistry. The drilling will occur on land and go under the seabed so marine life should not be affected by this. Underwater noise pollution is a possibility.

The RSPB have questioned why UCG was not banned along with fracking, “We are surprised that the Scottish government has excluded UCG, given many of the same concerns apply to this largely untested technology, like the risk of groundwater contamination,” said Alexa Morrison, conservation policy officer with RSPB Scotland. They did point out however the local people could try to deny planning permission to the scheme. The company involved involved is quick to point out that UCG and  fracking are in fact vastly different things that are being labelled together due to public confusion and not due to actually being similar.

It is currently believed that UCG produces only 20% of the CO2 given off from conventional coal gasification but this is yet to be verified. Exponents argue that doing it under the sea makes it safer and less polluting, although this has never been commercially done.

The Scottish Environmental Protection Agency (SEPA) has said that, although it cannot stop the project, it can impose pollution restrictions on the project. Regardless of the restrictions though the drilling, burning and pollution associated the scheme will not benefit any wildlife or the environment as a whole. At best the scheme will produce greenhouse gas, however groundwater contamination is a possible outcome. UCG has been tried around the world with mixed results.  Previous Australian and American projects have resulted in groundwater contamination in the past, however the projects in the UK mark the first time it has been tried under the sea. The comapny involved have said that what happened in Australia could not happen here due to changes in methods and better procedures. As the Chief Operations Officer of the proposed project said “you need to be very careful about comparing something different which happened somewhere else “. As mentioned previously on this blog, being against something doesn’t necessarily make you correct. Equally however, with high profile failures and low profile success, the public outcry is going to be a serious problem for companies to deal with.

It is a very interesting and controversial topic with local people and environmental groups being highly against the project. What will happen in the future is still unclear as the proposed gasification faces strong objection with the previous failures all being highlighted. The process does occur successfully around the world, although not under the sea.

Naturally, those opposed to fossil fuel use oppose this and so it is not surprising that many object as we try and move towards renewable energy. Being against the principle is fair but many sources are comparing projects which used very different technologies which is not a fair comparison As such, much of the commnonly quoted “evidence” is actually incorrect. As an environmentally friendly blog we are not in favour of fossil fuel use but nor are we disputing the evidence in favour of this project.

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