Coal Seam Gas
– Without the Hot Air
by Scott Bales
Depending on who you talk to, Coal Seam Gas can be portrayed as anything from the solution to our energy problems to an environmental disaster waiting to happen. We’ve compiled a simple guide to the subject, to help you sort the fact from the spin.
What is Coal Seam Gas, and what is fracking?
Coal Seam Gas (CSG) is a type of natural gas, which forms in underground areas where coal is present. It can be burnt and used as a fuel, similarly to conventional natural gas. CSG shares many properties with conventional natural gas, such as low CO2 emissions compared to coal. [Ed: reader Matt points out that doubts have been cast as to whether CSG truly does emit less greenhouse gas. He writes “Yes, it produces lower emissions than coal when burned, but that fails to take into account for the lifecycle of the gas which involves a lot of energy, particularly moving the water around, and significant fugitive emissions. We actually don’t have a good study on the lifecycle emissions from Australian CSG yet.”] More information here and .
Fracking is a method of harvesting gas, which can be used to access areas too deep to make drilling cost effective. Water, sand and various chemicals are pumped below the ground to create fractures. The coal seam gas can then escape up these holes and be harvested. This allows a very thin shaft to be drilled, making it much easier to drill long distances down or across.
Why is fracking now so popular?
Coal and conventional gas reserves are becoming increasingly scarce, and difficult and costly to acquire. Recent advances in fracking have made it possible to access previously difficult to reach gas, making underground gas reserves a financially sound investment, and arguably an important stop-gap to give more time for research into renewable energy sources.
What are the problems?
Earthquakes: Fracking has been found by many studies to have caused a large number of microearthquakes, ranging from 2 – 3.8 on the Richter scale. This should be weighed alongside the fact that there are over 100, 000 earthquakes in the range of 3 – 3.9, and over a million in the range of 2 – 2.9 worldwide each year. The Christchurch quake was magnitude 6.3 and very large earthquakes can reach around 8. Details of how the Richter scale works can be found here, but it is sufficient to say that powerful earthquakes can release millions of times the energy that microquakes proved to be caused by fracking do.
This is not to say that we should assume that fracking cannot cause dangerous earthquakes. It certainly is sensible to be researching the topic. However, you should be careful when reading attention grabbing headlines about earthquakes caused by fracking.
Chemical Contamination: A less commonly discussed concern about fracking is the use of harmful chemicals. Over 20% of the water pumped underground as part of the fracking process is not reclaimed, and often seeps into water catchments, dams, and eventually our drinking water. Those in favour of fracking are quick to point out that the water contains only small amounts (0.5%) of the various chemicals used, but some of these chemicals are dangerous even in small quantities.
There have also been cases of greenhouse gas methane escaping as a result of fracking activities, and this can take place in a wide area, not just at the drill site.
Additionally, the sheer amount of water used for fracking means that there is still a huge amount of these chemicals being poured into the ecosystem. It has been estimated that fracking uses 5400 GL of water per year – roughly triple that used in all households. Considering that 80% of this remains underground, where it cannot re enter the water cycle, and 20% returns to the surface contaminated, this is of major concern in a country which is predicted to only become more arid.
Short term solution to a long term problem
Whatever anyone may tell you about fracking, remember this: it can only be a temporary energy source. It allows us to reach additional energy deposits, but these are not going to last. We still need to consider the long term energy problem and find solutions that won’t pollute our drinking water.
People in Australia and abroad are moving to stop CSG expansion. Here are few links for more information about what’s happening.
And please remember that your voice counts: write to your local members of parliament and Tony Burke MP and let them know you support a moratorium on Coal Seam Gas exploration and mining in Australia.