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Author Topic: Can a capacitor reduce home electritity use?  (Read 24283 times)

Offline evan_au

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Re: Can a capacitor reduce home electritity use?
« Reply #25 on: 09/08/2016 22:43:40 »
Quote from: Scott Mayers
What is the OP here interpreting a 'capacitor' is though? It's not something a general consumer would be able to be concerned about nor could 'install' without a background in electronics.
There were rumors years ago that by connecting a big capacitor across an electricity meter, you could make it run backwards (or at least slow it down). I once had a holiday job calibrating electricity meters, and if you adjust them to be optimized for an inductive load (like most houses), it is possible that an extreme capacitive load could make them run (slowly) backwards. But any savings disappears as soon as you turn on a real load like an electric jug or a refrigerator.

In Australia, all traditional-style fluorescent light fittings came with an inductor (a "ballast" to smooth the current and kick-start the glow discharge) and a capacitor (to improve the Power Factor: PF).

Newer light fittings still have the inductor, but not a capacitor.

Long ago, I saw one of these capacitors "smoke", and I imagine they could cause the occasional fire, so I guess the regulations were changed so they were no longer required. Residential users don't have a huge impact on the power factor of the grid.

The newer compact fluorescents have an electronic ballast, and I imagine that these (and the numerous electronic chargers we use today) could be designed to have a PF close to 1.
 

Offline syhprum

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Re: Can a capacitor reduce home electritity use?
« Reply #26 on: 10/08/2016 09:47:15 »
There seems to some confusion about using a capacitor to reduce the voltage of your domestic supply , a capacitor in series with the supply will certainly do this but the reduction will vary with the load, what is required is a transformer the output voltage of which will vary little with the load but will in its self consume some power in iron losses.
In theory this would also require a capacitor across the line to correct for the magnetising current but domestic power supplies are metered in such a manner that that the power factor is of little consequence.

Apologies to Geezer I seem to have repeated largely what he had already said but his was the only mention of transformers in all the replies and I missed it
« Last Edit: 10/08/2016 10:16:23 by syhprum »
 

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Re: Can a capacitor reduce home electritity use?
« Reply #26 on: 10/08/2016 09:47:15 »

 

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