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I am trying to calculate energy savings for implementing a VFD and premium efficiency motor as an RTU retrofit. I am thinking to use the Variable Air Volume object to model the VFD, and changing the fan efficiency since it is a product of motor and fan efficiency. My question comes in to the Load Factor and % full rated speed of the fan air flow rate. Since I am going to make a lump system energy savings due to the interactive energy savings between the VFD and efficient motor, I need the % full rated speed (cubed) due to the fan affinity laws. Additionally I would need the motor load factor. I know that there is a design max air flow field in the variable air volume fan class, but I have not seen an output for hourly air flow rate to get the average % flow rate. Additionally I'm not sure about the load factor on the motor, although I may just assume the same load factor for both baseline and proposed cases. Any feedback on my line of thought or about the air volume fraction would be greatly appreciated.

I am trying to calculate energy savings for implementing a VFD and premium efficiency motor as an RTU retrofit. I am thinking to use the Variable Air Volume object to model the VFD, and changing the fan efficiency since it is a product of motor and fan efficiency. My question comes in to the Load Factor and % full rated speed of the fan air flow rate. Since I am going to make a lump system energy savings due to the interactive energy savings between the VFD and efficient motor, I need the % full rated speed (cubed) due to the fan affinity laws. Additionally I would need the motor load factor. I know that there is a design max air flow field in the variable air volume fan class, but I have not seen an output for hourly air flow rate to get the average % flow rate. Additionally I'm not sure about the load factor on the motor, although I may just assume the same load factor for both baseline and proposed cases. Any feedback on my line of thought or about the air volume fraction would be greatly appreciated.

I am trying to calculate energy savings for implementing a VFD and premium efficiency motor as an RTU retrofit. I am thinking to use the Variable Air Volume object to model the VFD, and changing the fan efficiency since it is a product of motor and fan efficiency. My question comes in to the Load Factor and % full rated speed of the fan air flow rate. Since I am going to make a lump system energy savings due to the interactive energy savings between the VFD and efficient motor, I need the % full rated speed (cubed) due to the fan affinity laws. Additionally I would need the motor load factor. I know that there is a design max air flow field in the variable air volume fan class, but I have not seen an output for hourly air flow rate to get the average % flow rate. Additionally I'm not sure about the load factor on the motor, although I may just assume the same load factor for both baseline and proposed cases. Any feedback on my line of thought or about the air volume fraction would be greatly appreciated.

I am trying to calculate energy savings for implementing a VFD and premium efficiency motor as an RTU retrofit. I am thinking to use the Variable Air Volume object to model the VFD, and changing the fan efficiency since it is a product of motor and fan efficiency. My question comes in to the Load Factor and % full rated speed of the fan air flow rate. Since I am going to make a lump system energy savings due to the interactive energy savings between the VFD and efficient motor, I need the % full rated speed (cubed) due to the fan affinity laws. Additionally I would need the motor load factor. I know that there is a design max air flow field in the variable air volume fan class, but I have not seen an output for hourly air flow rate to get the average % flow rate. Additionally I'm not sure about the load factor on the motor, although I may just assume the same load factor for both baseline and proposed cases. Any feedback on my line of thought or about the air volume fraction would be greatly appreciated.