Feasibility Study Of CCHP Systems In A Neighborhood Project In Changsha Jin-waitan

With the improvement of people’s living standards, air conditioning becomes the basic requirements for residential and non-residential buildings. District heating and cooling (DHC) or combined heating cooling and power (CCHP) system is a rational way for domestic heating and cooling in densely populated towns, especially in areas with hot summer and cold winter such as Changsha. DHC or CCHP can maximize primary energy efficiency by cascading the energy uses with different building types.On the basis of the principles of Green Infrastructure and Building (GIB) in LEED for Green Neighborhood Development (LEED-ND), this paper studies the technical feasibility, economic soundness, and environmental effectiveness of a CCHP energy system in Jinwaitan project, a6.5million square feet mixed-use neighborhood development project in Changsha, Hunan Province, China. Various energy efficient measures are applied in the building design, and the simulation results by Energy Plus show that the buildings saves31.8%electricity and34.85%thermal energy comparing to the basecase as defined by ASHRAE90.1-2007. Two case are compared in the study. The two energy systems are:System One. two internal combustion engines (ICE) with power generation capacity2100kWe each, and associated Water-LiBr absorption chillers to recover the rejected heat from ICEs. The system will provide electric base load for buildings, and the recovered heat will be used to produce heating and cooling for buildings; System Two, The buildings will use electricity from power grid, and the heating and cooling will be provided by natural gas fired absorption chillers.The study shows that System one can operate13,848hours annually with10,175hours in full load operation. The annual energy efficiency of System one is about83.6%. System one demonstrates31%more efficient than System two. The cost benefit analysis indicates that System one saves￥15,780,000RMB Yuan operation cost annually, and the payback period for System one is about2.9years. The environmental analysis shows System one will save2,418tons of Carbon Dioxide emission annually than System two.