This document discusses how geographic information technology (GIT) can help plan a green, low-carbon sustainable city. GIT tools like GIS allow planners to integrate spatial data on factors like population, land use, wind patterns and more to evaluate suitable locations for renewable energy projects. For example, GIS could be used to identify regions with high energy demand and steady winds for a potential wind farm by overlaying wind data with population and land use maps. GIT also enables simulation of scenarios to test things like voltage fluctuation from wind turbines. The document also discusses how building design can promote sustainability through better ventilation and consideration of building height and density to reduce urban heat islands.