Monday, September 9, 2019

Life Cycle Assessment of Greenhouse Gas Emissions From Natural Gas And Literature review

Life Cycle Assessment of Greenhouse Gas Emissions From Natural Gas And Biomass Power Plants - Literature review Example This means that all stages in the life of the product is assessed. The assessment evaluates the impact of extraction, processing, transportation of the raw material used for processing and fuels along the operation of the plants to the final decommissioning (Mann and Spath, 2011). Green house gases - GHG is the gas that leads to greenhouse effects by absorbing and emitting infrared radiation, leading to the gradual increase in temperature. Main gases that are GHG are water vapour, CO2, Methane, Nitrous Oxide, Ozone and CFC or Chlorofluorocarbons. These are available naturally in the environment but when the percentage is increased beyond the specified limit, it can lead to global warming. The unit used for measurement is in gCO2e/kWhe or grams carbon dioxide equivalent per kilowatt hour equivalent (Weisser, 2010). Carbon capture and storage - CCS is a process used to separate CO2 from industrial and energy related resources. It includes transportation to the storage location and isol ating the gas from mixing with the atmosphere. Reduction of emissions of power plants depends on the CO2 capture system used. Cost of CSS is high and as seen in the below figure, it costs 10 USD/ ton of CO2 to transport the captured carbon to 800 kilometres. Smaller volumes cost higher. Hence, sites near to the power plant are preferred (PACE, 2009). Figure 2.1. Cost of CSS (Azar, et al, 2006) Carbon storage needs a lot of effort in identifying the proper site and ensuring that there is no leakage. Please refer to the following figure that gives the potential for underground carbon storage. Figure 2.2. Potential for underground carbon storage (Azar, et al, 2006) Advantages of carbon capture is that it provides a means to control emissions and to... The paper has examined the LCA of natural gas and biomass plants with and without CCS. It is seen that natural gas has much higher emissions and even with CCS, GHG are still high. Biomass has much lower emissions and with CCS, the fuel source is very attractive. However, biomass fuel is difficult to procure and costly to transport in bulk. This paper gives the results from the literature review and a brief comparison of the two fuels is done to understand the manner in which they perform. CNG is highly commercialised and about 37% of power in the world is generated through CNG. Sufficient stocks are also available and the level of energy security is high. However, with biomass, the energy security is less and extensive use of wood, barley and maize for production of ethanol can lead to shortage of grain and can impact the food security. Development of transport and logistics technology such as refrigerated trucks and ships, pipelines and dedicated outlets have allowed this fuel to become portable. This means, natural gas mined in Nigeria is transported economically to Europe or even China. The author of the report this flexibility and ease of use is not possible with biomass. Compressed gas has a much higher GHG emission and more power is consumed in processing and transporting the fuel. Biomass has a much lesser amoun t of GHG emissions but the fuel cannot be transported economically over longer distance. Hence, it use is only in power plants in the area where plant vegetation and wood is available.

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