I don’t know where all these “it doesn’t work” comments are coming from.

Are these (uneducated) comments coming from electrical engineers or just sceptics who don’t understand how AC electricity actually works?

Yes they DO work.

They achieve up to 70% power saving (at the meter) but typically around 30-40% saving in a house/business with lots of motors (Aircon, fridges, pool/spa pumps, washing machines, dishwashers etc)

They correct for a few things including power factor errors introduced onto the home or business power circuits due to inductive (reactive) loads.

Country Energy says…

Power Factor is a measure of how effectively incoming power is used in your business and is defined as the ratio of real (working) power to apparent (total) power.

Real power is power that is put to productive use in your business and apparent power is the total power supplied by the distribution system to your business.

Power Factor is expressed as a value between zero and one.

If the ratio between real power and apparent power – the Power Factor – is 1, then all of the power supplied is being used for productive work. However, a Power Factor of 0.7, for example, indicates that only 70% of power supplied to your business is being used effectively and 30% is being wasted. The wasted power is known as reactive (non-working) power.

The reactive (nonworking) power increases the amount of apparent (total) power your business draws through the distribution system and has a negative impact on your Power Factor.

Reactive power is most often used by inductive loads such as transformers, electric motors, fluorescent lighting and air conditioning motors, which can make up a large proportion of the power consumed in some businesses.

If your Power Factor is low, you may be paying more than you need to for your electricity.

http://www.countryenergy.com.au/asset/cms/pdf/business/energyinsight/PF_Power_Factor.pdf

Energex Says…

Power Factor Explained (great brochure)
http://www.energex.com.au/network/network_prices/pdf/brochure_power_factor_explained.pdf

The Eathwise Power Saver constantly dynamically tracks the reactive (inductive) power consumption and then introduces an equal but opposite (capacitive) reactive load. This causes the power meter to see the “REAL” power which can be up to 70% lower (depending on the actual load).

I do not have enough data yet on the OZ Power Saver. Their site is thin on technical info but it probably uses similar logic. Maybe it is just a bank of capcitors?

Want to learn more?

Go to http://electricity-power-saver.com

and request the power saver report

(Disclosure: I sell Earthwise Power Savers)

This entry was posted on Monday, January 31st, 2011 at 23:57 and is filed under Earthwise, Power. You can follow any responses to this entry through the RSS 2.0 feed. Responses are currently closed, but you can trackback from your own site.