In　order　to　improve　the　utilization　of　solar　energy　in　buildings,　a　new　system　combining　an　active-passive　ventilation　wall　with　phase　change　material　(PCM)　and　solar　concentrators　was　proposed,　and　a　two-dimensional　unsteady　numerical　heat　transfer　model　of　the　proposed　wall　was　established　and　validated　using　data　collected　from　field　measurement.　Using　this　model,　influencing　factors,　namely,　velocity　and　inlet　temperature　of　air,　thickness　and　length　of　air　tunnel,　have　been　identified　to　have　influence　on　its　thermal　performance.　Then　optimum　operational　conditions　have　also　been　identified　to　guide　the　optimal　design　of　the　proposed　wall　and　the　application　of　solar　energy　in　buildings.　(C)　2016　Published　by　Elsevier　Ltd.