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PFC for home use Answered

I'm thinking about using PFCs (power factor correction capacitors) for my whole house. Has anyone here done it? I currently use PFCs on my neon sign transformer (an d it works), but I have a question. Why wouldn't one capacitor effect my whole house? or does it and it's just because it's a tiny cap (only about 20uF) that the results are negilagble? Also, what stops it from just affecting my house to the whole power grid? thankyou EDIT: I just read somewhere that the power company for residential homes charges the same whether you use PFCs or not, they just somehow mesure the real power... Is that true?



9 years ago

My understanding matches 111010010110's: PFC correction won't change your power meter one way or the other, but has a more subtle effect on the efficiency of the overall power distribution system.

psh, well don't mean to sound like a jerk but it's about the money, not being green (lol, if I had the caps right now i'd do it, but I don't feel like spending 70 dollars worth of caps on my house if it doesn't pay for it's self.

PFCs do affect the whole grid. thats why power company does want you to use PFCs - their generators and transformers do feel the difference

however homes are very small PF destructors compared to factories with huge motors. thats why most power co's bother to require PFC at factories only

you should match the capacitance to the load. the closer it matches the better the results are. thats why individual cap for each load is usually the best solution. the cap is exactly sufficient to balance the load and is switched on and off together with the load

i wrote some explanation about PFC myself here which may be usefull https://www.instructables.com/id/Mod_light_fixture_to_low_watt_PL/ see steps 9 and 16

only inductive loads (motors / transformers / lamp ballasts etc) power factor can be corrected with a capacitor. thats cause the wave shape of the current is still sine and is just moved in phase. many devices like computers and CFLs have power factor issues too but of another type - current waveform is spikey and not sine. this cannot be corrected with capacitor and requires more complex PFC system

PFC does not affect the reading of your meter (it may however with future meters) but affects the efficiency of the system. for example a fluorescent lamp takes 11 W. with PFC the source supplies say 13 W of which 2 are wasted as heat in the ballast. without PFC the lamp and ballast still use the same 11 and 2 W respectively. but additionally similar amount of power is wasted as heat in the generator and transformers of the power grid after 'bouncing' from the lamp ballast