Along with the methane produced by living microbes during the decomposition process in biodigesters, methane gas can also be sourced directly from the ground where it has been trapped for millions of years with the coal and surrounding rocks as the coal was formed.
This methane trapped in the ground may one day find itself escaping and being released into the atmosphere. As methane is a greenhouse gas which can trap heat from the sun and prevent it being lost back out into space, an increase in the amount of methane in the atmosphere can cause the average mean temperature of the planet to rise. This has serious implications for the environment and the health and wellbeing of all living creatures as issues including crop failure, extreme weather and coastal flooding through melting polar ice caps causing a rise in sea levels are all consequences of climate change.
Successfully capturing this methane to be used as a fuel source will prevent its future release into the surrounding air and rising up to the atmosphere, which will prevent a future negative impact upon the environment as described in the paragraph above. Not only this, but burning methane and using it as a fuel is cleaner and better for the environment than burning a fossil fuel such as coal or oil, as the harmful pollutants given off as a consequence of the combustion process are of a lower concentration. Burning methane will therefore be far more preferable in terms of preventing damage to the environment than relying upon fossil fuels to generate the required power.
There are disadvantages associated with methane recovery though. For starters, methane gas is extremely volatile in that the risk of explosion is high, and is the reason why landfill sites, even those cleared and used for other purposes such as an industrial estate, need to be carefully monitored to prevent the build up of methane and potential explosions occurring which can put the health and safety of anyone nearby at serious risk.
Along with the possible dangers, methane recovery can be awkward, difficult and expensive to achieve, particularly where newly-developed technologies and processes such as forced carbon dioxide displacement are involved. Not only can these high costs prevent methane recovery processes from beginning at all, but even ones that have started may mind that the costs and difficulties involved soon make the process unviable in the long term. Whilst there will be many who will argue that no price can be put on protecting the environment and safeguarding planet Earth for future generations, when the methane recovery process is being funded by a private company (or even cash-strapped governments!), they will require a financial return and at the very least not be losing money on the endeavour in order to continue with it.
Related Environmental Course
NEBOSH Environmental Certificate. Those attending this course will learn a wealth of information regarding how the activities of a business and its employees can negatively impact the environment, along with the safeguards and control measures that can be put into place to help reduce the likelihood and potential for an accident or environmental incident to occur. To find out more information regarding the NEBOSH Environmental Certificate and the other NEBOSH courses we offer please choose the "NEBOSH Courses" option from the "Health & Safety" drop-down menu at the top of the page.