How to stop chiller from running while thermal energy storage still has capacity?
I'm looking into the IceStorage-Series-ChillerDownstream.idf energyplus example file which uses a ThermalStorage:Ice:Detailed object and other controlling objects to use thermal energy storage for cooling.
In particular, I'm trying to decrease the Time Dependent Valuation (TDV) total for a building. Thermal energy storage is perfect for this since the tank can be charged with a chiller during off peak hours at night and discharged during on peak hours for cooling instead of the chiller.
However, I ran the IceStorage-Series-ChillerDownstream.idf energyplus example file during the months of June, July, and August and measured the TDV with and without use of the Ice Tank, and the difference in TDV was small, and sometimes increased if I autosized certain values.
Looking deeper into the simulation results, looks like the Ice Tank isn't being fully utilized with the chiller still running most of the time.
As you can see, the chiller is running when it's hot outside during on peak hours and the Ice Tank still has a lot of cooling capacity left.
I tried making the Ice Tank capacity 100 times larger, so WAY more than the building needs, but the chiller still turns on when the Ice Tank could easily handle all the cooling load.
So my question is: How do I get the chiller to run only when charging the Ice Tank at night, or during the day AFTER the Ice Tank has been completely used up?
