Preliminary assessment for global warming potential of leading contributory gases from a 40-in. LCD flat-screen television

As liquid crystal display (LCD) flat-screen televisions increase in popularity, their potential contribution to global warming has received wide attention. This study presents global warming impacts resulting from the life cycle assessment (LCA) of LCD flat-screen televisions for key global warming contributors from the “cradle-to-gate” and use stages of the product’s life cycle. The emissions from nitrogen trifluoride (NF₃), a greenhouse gas with a global warming potential (GWP) 17,000 times more potent than carbon dioxide (CO₂), are not monitored in the Kyoto Protocol. Emissions in the cradle-to-gate and use stages were modeled in this study according to their GWP (kg CO₂ equivalent), focusing and analyzing the most significant source of NF₃ emissions.

NF₃ is used during the manufacturing process of LCDs to clean the vacuum chambers. In this study, a system diagram of the cradle-to-gate stage and use stage of a 40-in. LCD television was proposed using the software package Gabi®, particularly investigating NF₃ to determine its possible effects on global warming based on a typical LCA.

The energy inputs in the use stage of the LCD flat-screen television resulted in major global warming impacts, while the contribution of GWP resulting from NF₃ was trivial. However, as energy efficiency continuously improves over time, the GWP resulting from NF₃ may become significant. Findings in this study allow industry to focus on those critical stages of the production life cycle that most directly affect global warming while permitting government agencies to enact proper regulations to help decrease CO₂ equivalent emissions.

The preliminary assessment of our LCA also offers manufacturers the ability to determine the largest sources of greenhouse gases and their connection in the life cycle analysis of a product. This extension may help guide legislation and industrial management in the future. For further decision making, an in-depth sensitivity analysis may be needed to strengthen the results.