Energy Saving with Digital Scroll compressor system

[nehetesj]

Hi....

I have a very fundamental question..Why digital scroll compressor system saves energy in Air Conditioning application. Can anybody help me out to understand this.
Is there any case study reference to compare Energy consumption of Digital Vs Fixed scroll system.
I understand digital helps in maintaining precise temperature but why it consumes less energy.

Rgds
Sachin

[sendhilkmar]

As per my understanding digital scroll modulates the capacity by Loading (pumping) and unloading (No pumping)to meet the demand. The energy saving comes at part load condition whereas the regular scroll cycles to meet the demand, by doing so it pulls extra cooling which is not useful and so the power consumption also.

[nehetesj]

That I can understand. But Digital systems motor will keep on running at part load, where as fixed system is OFF once the condition is achieved. Run time of fixed system will be very less at part load.

[NoNickName]

In the disengaged condition of a digital scroll, the rotors are not engaged. Therefore the energy consumed by the motor is limited to the energy required for self rotating, that is very next to nil.

[sendhilkmar]

Sachin,
When the compressor is loaded' the power consumption is 100% and in unloaded condition it is less than 10% (just to keep the motor running). So you have to calculate the total power consumption by the sum of time average method. The total run time of fixed system shoul be higher than the loaded time of Digital.