Evaluation of the Energy Performance for a nZEB Office Building under Specific Climatic Conditions

This paper presents the results from simulation work regarding the design of a net zero energy office building with a mixed-mode ventilation system which assures the thermal comfort of the occupants according to the ASHRAE 55/2010 Standard, with a rational consumption of energy and a minimal environmental impact. This was a particular difficult task as the studied city, New Delhi, is one of the most polluted in the world. The study relied on the use of easily accessible building materials and customary Air Conditioning (AC) equipment, in order to meet the requirements. For this purpose, three different AC systems had been selected: a Chilled Beams (CB) system, a Fan Coil Units (FCU) system, and a Variable Refrigerant Flow (VRF) system. All the simulations have been performed within the Design Builder platform, a user-friendly interface of the Energy Plus software. The chilled beams AC system came on top of the energy performance ranking, with 4,6% less energy consumption than the fan coil units system and 2,3% less than the variable refrigerant system, for a payback period of 11,3 years. As for the energy production, 160 modules of photovoltaic panels with a total energy yield of 64260 [kWh/year] were used to cover the building electrical needs (lighting and appliances).