power factor correction

[dlt27]

Hi can anyone help please.
I was asked the following question today.
An organisation has determined their sites total power is 25KVA and it's power factor is 0.8. Calculate the site's useful power( including units). Could anybody please help or provide me with equation to calculate the answer...
Much appreciated.

 

[Darkwood]

We do not actively promote giving or helping with answers to homework in the main forum, there are a few reasons for this but if you PM a Mod' and ask for access to the training section then you would be helped by like minded trainee's some who of which will be doing the same homework.

 

[Des 56]

Apparently there is a section of the forum where power factor is discussed and thats true

 

[dlt27]

It's not homework. I just had an auditor ask me today. I couldn't remember. I though it was 0.8 x 25 so equals 20 KW. However it's been a long time....

 

[Andy78]

Apparently there is a section of the forum where power factor is discussed and thats
true

Lead me to it as my knowledge on this subject is lagging a bit.

 

[Des 56]

I suppose I should have some sort of reactance to the posts

 

[dlt27]

I know Pf = useful power/ total power. Its the cos bit that is throwing me.
Is my calculation right or am I missing something��

 

[Leesparkykent]

I know Pf = useful power/ total power. Its the cos bit that is throwing me.
Is my calculation right or am I missing something��

Power Factor is expressed as COS phi Ø (The angle between Apparent Power and Active power)

kVA x pf=kW