This study presents an energy performance evaluation for new Yaodong dwellings located in the Zaoyuan village in Yanan city, China. Numerical simulations of heating and cooling energy consumption are conducted on the building models using the energy simulation program Energyplus. The energy performance is assessed using the indices of energy consumption, CO2 emissions, and heat balance analysis as well as the air temperature profiles. The results show that the new Yaodong dwelling consumes 39% of the heating energy used by the old Yaodong dwelling and only 23% of that used by a brick house, and the energy consumption during the cooling season is zero. Convective heat transfer by warm air from the sunspace to the inner rooms can further reduce the heating energy consumption by approximately 28%. This study shows that the new Yaodong dwelling, with its traditional heavy envelope, attached sunspace and improved thermal insulation, can significantly reduce energy consumption and CO2 emissions compared with those of the old Yaodong and brick houses. (C) 2013 Elsevier B.V. All rights reserved.