Today world consumes approximately 600 Exa Joules of energy per annum, which is equivalent to approximately 275 million barrels of oil equivalent per day. If the global business carries on as usual i.e. present energy consumption trend continues, the global energy consumption could increase by 30% in next twenty five years. Presently the global energy demand is met mostly by fossil fuels i.e. oil, natural gas and coal. Fossil fuels meet approximately 80% of the global energy demand, while other sources of energy i.e. nuclear, hydro, bio energy and renewables (solar & wind) meet remaining 20% of the energy demand. Among fossil fuels, oil meets approximately 30% of global energy demand while coal and natural gas meet approximately 27% and 23% of that demand respectively.
Key question is whether this energy-mix (dominated heavily by fossil fuels) is sustainable? Fossil fuels emit greenhouse gases in process of producing energy, which leads to global warming. Presently, approximately 36 billion tonnes of CO2 (a major greenhouse gas) related to energy is emitted in atmosphere. If there is no check on emission of greenhouse gases, its consequences on climate could be catastrophic. Some of the islands may face existential threat due to risk of being inundated due to rise in seawater level as a result of global warming, besides other impacts such as floods, droughts, loss of biodiversity to name few.
Global concern on climate change due to global warming has manifested in Kyoto Protocol in 1997 followed by Paris Agreement in 2015. Paris agreement sets a target to limit global warming level to well below 2 deg C and preferably 1.5 deg C from pre-industrial levels. The only way to limit the level of global warming is by limiting greenhouse gas emissions. This requires energy transition from present high CO2 emission energy-mix to low CO2 emission fuels. Several countries and groups such as European Union, US, Canada, Japan and many others have announced the goal to achieve net zero CO2 emissions by 2050.
Of the three fossil fuels, coal emits highest quantity of CO2 followed by oil and natural gas in that order for every unit of energy produced. Natural gas emits approximately half as much CO2 as coal and approximately three quarters of CO2 emitted by oil. If combustion of natural gas is accompanied with carbon capture and storage (CCS) technology, CO2 emissions can further be reduced by 85-90%. This means maximizing the use of natural gas as a source of energy along with use of CCS can bring down CO2 emissions substantially. So, if a fossil fuel energy-mix has to be sustainable, it would have to maximize the share of natural gas along with application of CCS technology.
But, major constraint in use of natural gas is its restricted availability to many countries. Its production is concentrated in a few countries only. Currently, world produces approximately 4000 billion cubic meters (bcm) of natural gas per annum, out of which US alone produces nearly 1000 bcm followed by Russia at approximately 650 bcm. That is, approximately 40% of global natural gas production comes from US and Russia only. If we add Iran, China, Qatar, Canada and Australia, nearly 65% of global natural gas production is contributed by these seven countries. If we further add Saudi Arabia and Norway, nearly 70% of global natural gas production comes from those nine countries.
In order to make natural gas available in different parts of the globe, it has to be transported to other countries from major producing countries. Though natural gas is transported to some countries through pipelines e.g. from Russia to European countries, it’s economically unviable to lay subsea pipelines to transport natural gas to other countries which are connected with producing countries through sea. So, there is another economically viable option to supply natural gas to such countries. That is, supply liquefied natural gas (LNG) through LNG carriers through sea routes.
Presently, nearly 1250 bcm per annum natural gas is traded internationally, of which approximately 60% traded through pipelines and around 40% as LNG through ships. While present global natural gas liquefaction capacity is approximately 450 million tonnes per annum (mmtpa), it is expected to climb to approximately 750 mmtpa in 2026. This shows the global acceptability of LNG as a fuel of future and that it can play a key role in sustainable and low-carbon energy transition.
About Author: Satyendra Kumar Singh, B.Tech. (Chemical Technology) + M.B.A., is proprietor of Satsha Management Services-an award winning design engineering and management consulting company (www.satshamanagement.com). He possesses approximately 30 years’ experience in engineering consultancy in process and energy industries. Satyendra has authored several papers on energy, business and management, which have been published in some renowned journals/magazines such as ‘Chemical Engineering’, ‘Process Worldwide’, ‘Modern Manufacturing India’. He may be reached at satyendra.singh@satshamanagement.com, Ph. +919811293605.
