power factor

[8625]

This queation may sound very vague,

here it goes,

my mothly energy consumption is 8700 units( KWH) at a power factor of 0.7 . if the PF is improved to 0.9 what will be my energy consumptionin KWH assuming no changes in loading.

thanks.

 

[wowski]

Theoretically your KWH shouldn't change. The power factor is a measure of the ratio between real (kW) and reactive(kVAr). You can improve the power factor by increasing your kW load and keeping the kVAr component the same, or by reducing the kVAr and keeping the kW the same (as you say you will do).
You may notice a small difference as the reactive component can cause heating effects, and hence increase losses, but this would depend upon the size of the loads involved.

 

[230842]

Wowski is right. If there are no changes in loading, you can improve PF by the addition or capacitor batteries which generates reactive power without,theoretically, real (kWh) energy consumption (in practice, the actual increase is negligeable). Doing so, the equipment investment is largely compensated, in most Countries, by the bonus in energy unit (kWh) price. Julian

 

[jbartos]

Suggestion:
1. Theoretically, you cannot chage power factor without a change in loading in terms of kVA, or VA
2. Sometimes, if you lower kW you may either increase or decrease PF depending on nature of loads. E.g. if you increase load on the motor shaft, kW or HP, of lightly loaded motor the power factor will increase with increased motor shaft load, kW, and vice-versa.
3. If you add power factor compensating capacitors, the input voltage and kWhr may increase along with the power factor sufficiently enough to notice it on your bill.