Retrofit

Retrofitting Strategy	Using spot cooling for local air-conditioning zone
	Spot cooling is designed to provide cooling air to limited required area or certain time period without the need to cool the entire area that is not normally occupied. Energy-efficient ceiling fans can be used to provide quiet air movement to cool semi-outdoor areas.
	Consideration
	The required air-conditioning zone/space may not aims to satisfy the thermal comfort requirement of the occupants but the operation requirement of both operators and the operation system.
	Estimated Saving
	Waterside: 1/COP_CH_PRE * QBLDG_PRE * OPHR_PRE,yr – 1/COP_CH_POST * QBLDG_POST * OPHR_POST,yr Where COP_CH = 0.605COP_CH_SM + 0.395COP_CH_WN COP_CH_SM = (COPa_SM + COPb_SM)/2; COP_CH_WN = (COPa_WN + COPb_WN)/2 QBLDG_PRE = 0.605[0.77(0.88NCH_SMQCH_SM + 0.12NCH_WNQCH_WN)] + 0.395[0.596(0.184NCH_SMQCH_SM + 0.816NCH_SMQCH_SM)] QBLDG_POST = QBLDG_PRE * (LWH)_POST/(LWH)_PRE Airside (AHUàSCU): SkW_AHU_PRE * OPHR_PRE,yr – SkW_SCU_POST* OPHR_POST,yr Where SkW_AHU_PRE = (0.605LF_SM,PRE + 0.395LF_WN,PRE)NAHU_PREkW_AHU_PRE SkW_SCU_POST = (0.605LF_SM,POST + 0.395LF_WN,POST)NSCU_POSTkW_SCU_POST For CSD: LF_SM = LF_WN = 1, For VSD: LF_SM = 0.795, LF_WN = 0.562; For EC or DC-motor: LF_SM = 0.71, LF_WN = 0.38 OPHR,yr = hr/dayday/wk52 Please click HERE to view the list of terminology.