The sustainability of LNG evaporation

Numerous LNG (Liquefied Natural Gas) import terminals are under construction to fulfil the growing demand for energy carriers. After storage in tanks, the LNG needs to be heated and evaporated, also called ‘regasified’, to the natural gas needed in households and industry. Several options exist for providing the required heat. In the interest of sustainable development it is important to decide carefully upon which technology to apply for LNG evaporation. In this research, three options for LNG evaporation have been investigated: using the waste heat from a power plant, integrating the LNG terminal with an air separation unit and an oxy-fuel power plant, and combining the evaporation process with an Organic Rankine Cycle to produce electricity. The research consisted of an environmental life cycle assessment, calculation the life cycle costs, conducting a social life cycle assessment and determining the cumulative exergy extracted from the natural environment (CEENE). The option in which the LNG terminal is integrated with an air separation unit and an oxy-fuel coal power plant appeared to be preferable. This research is part of a study after the effects of involving exergy analysis in decisions regarding future energy supply on the environmental, economic and social aspects of its sustainability.