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ASHP End Uses Heating (ELECTRICITY is always 0)

asked 2020-05-14 14:54:36 -0600

sergerwehbe gravatar image

updated 2020-05-15 10:53:57 -0600

Hi All, Please, I'm trying to Design a heating/cooling system using ASHP and chiller, I added all objects related (WaterHeater:HeatPump:PumpedCondenser, WaterHeater:Mixed and Coilwaterheating:air to waterHeatPump:Pumped I set all the schedules to be always ON. I got the electricity consumption ( End Uses Cooling Electricity) In cooling but for heating is always 0!! I linked these 2 loops ( chiiler and ASHP) to a fan coil terminal units inside the building, I checked all output values such as heating coil capacity, tank Temp, Pump flow rate,.. everything goes well and the tank temperature goes up and down like the heating system is working properly but the Heating end Uses is always 0. In addition, I run the E+ example files ( ASIHPMixedTankTable.IDF, HeatPumpWaterHeaterStratified.IDF...) I always got the same result (End uses heating Electricity is 0). I noticed in the Plant Loop Demand Report Monthly For Hot Water Loop, "PLANT SUPPLY SIDE COOLING DEMAND RATE" and "PLANT SUPPLY SIDE HEATING DEMAND RATE" both columns have values during heating months. (Plz see Link Thank you in advance.

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answered 2020-05-14 15:28:30 -0600

updated 2020-05-14 15:28:49 -0600

It sounds like you modeled a heat pump water heater (HPWH), which heats water while rejecting heat to air. Usually, air-source heat pump (ASHP) systems heat or cool air while rejecting heat to another air stream.

Any heating for this HPWH will appear as electricity use in the "Water Systems" category and not the "Heating" category. If you wanted to separate this HPWH intended for space heating from other water heaters intended for domestic hot water or other purposes, then use a different End-Use Subcategory for the WaterHeater:Mixed object. You will then see the energy use for the subcategory appear in the End Uses by Subcategory table of the Annual Building Utility Performance Summary report.

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Well done, Thank you

sergerwehbe gravatar image sergerwehbe  ( 2020-05-15 02:05:33 -0600 )edit

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Asked: 2020-05-14 14:54:36 -0600

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Last updated: May 14 '20