We analyzed energy consumption by a newly constructed part of a city in Korea to forecast the LNG demand for 14 years. The electricity, heating, cooling, and hot-water demands for a cogeneration-based CES (Community Energy System) accommodating 86,000 people in 29,000 houses are estimated using load models developed through direct measurements and statistical surveys. Based on published occupancy rates and forecasts of the rate of increase in energy consumption by third parties through independent study, the energy demands were driven in the form of 8760-h time series for each of the 14 years. Next, we simulate the demand-supply matching processes of a specifically chosen cogeneration engine for the CES to forecast the LNG consumption and the electricity trade for each year. We simulated the demand-supply matching processes with an automation tool specifically developed for this study. The methodology we established in this study can be applied to similar problems which may arise anywhere in the world. (C) 2014 Elsevier Ltd. All rights reserved.