I am trying to model a rainwater collector on the roof of a building that will be sent to a rainwater tank as a WaterUse:Storage component in EnergyPlus. That tank is then connected to my DHW WaterUse:Connections component as the "Supply Water Storage Tank Name" to supply cold water when the tank has ample volume, otherwise mains water will be used. Here are my issues:
1) When it is raining, my output .csv file doesn't show a change in rainwater tank volume from the initial value.
2) My annual simulations show no change in mains water used for DHW loads whether rainwater is collected or not.
3) The volume for the graywater tank also doesn't change from the initial value.
Here is an excerpt from the .idf file:
WaterUse:Connections,
Restroom DHW Connections,!- Name
Restroom DHW Inlet Node, !- Inlet Node Name
Restroom DHW Outlet Node, !- Outlet Node Name
Rainwater Tank, !- Supply Water Storage Tank Name
Graywater Tank, !- Reclamation Water Storage Tank Name
, !- Hot Water Supply Temperature Schedule Name
, !- Cold Water Supply Temperature Schedule Name
, !- Drain Water Heat Exchanger Type
, !- Drain Water Heat Exchanger Destination
, !- Drain Water Heat Exchanger U-Factor Times Area {W/K}
Restroom DHW Equipment; !- Water Use Equipment 1 Name
WaterUse:RainCollector,
Rainwater Collector ,!- Name
Rainwater Tank , !- Storage Tank Name
CONSTANT, !- Loss Factor Mode
0.2 , !- Collection Loss Factor
, !- Collection Loss Factor Schedule Name
100000, !- Maximum Collection Rate
Rainwater Collector Surface ; !- Collection Surface Name
WaterUse:Storage,
Rainwater Tank, !- Name
Rainwater Harvesting, !- Water Quality Subcategory
, !- Maximum Capacity {m3}
5, !- Initial Volume {m3}
, !- Design In Flow Rate {m3}
, !- Design Out Flow Rate {m3}
, !- Overflow Destination
None, !- Type of Supply Controlled by Float Valve
, !- Float Valve On Capacity {m3}
, !- Float Valve Off Capacity {m3}
, !- Backup Mains Capacity {m3}
, !- Other Tank Name
ScheduledTemperature , !- Water Thermal Mode
Rainwater Temp Schedule , !- Water Temperature Schedule Name
, !- Ambient Temperature Indicator
, !- Ambient Temperature Schedule Name
, !- Zone Name
, !- Tank Surface Area {m2}
, !- Tank U Value {W/m2-K}
; !- Tank Outside Surface Material Name
Schedule:Constant,
Rainwater Temp Schedule, !- Name
Any Number, !- Schedule Type Limits Name
16; !- Hourly Value
I have created a Site:Precipitation object with an annual schedule from the PrecipitationSchedulesUSA.idf dataset, and that works fine. Any help would be greatly appreciated. I've thought about if there should be a pump connected to the rainwater loop, but there aren't input or output nodes for the WaterUse:RainCollector or WaterUse:Storage components.
