KDHC is a government run energy company established with the aim of actively responding to climate change agreements and promoting energy savings and people’s healthy life., efficiently implementing them. KDHC is the largest Korean district energy business that has more than 30 years of experience in business and heat supply network in Seoul metropolitan area. In Dongtan2 project, LNG combined heat and power plant capable of producing up to 757MW of electricity and 524Gcal/h of heat at the same time was completed by investing about 1 billion Dollars in project costs to supply stable district heating and cooling to the new city and to supply electricity to the nearby metropolitan area. Business competitiveness can be secured by establishing an integrated/connected heat transfer pipe with the existing district energy facilities around Dongtan 2. This has the effect of using the surplus heat from the existing facilities. At the same time, it contributes to stabilizing heat tariffs by drastically reducing investment/operation costs. Also, by maximizing wasted heat, we can create excellent energy savings and air environmental improvement. By utilizing new and renewable energy, wasted heat from power generation, significant energy savings and environmental improvement were achieved, such as a 32% reduction in energy compared to individual heating, an 89% reduction in air pollutants, and a 57% reduction in greenhouse gases.