air conditioner electricity-saving appliance

[Lc_shi]

Hi Sir
I've read many advertisement in my place to sell air conditioner electricity-saving appliance. It's said to save 20~30% electricity consuming. I don't know what the mechanism for it. Is there the similar products in your place? Is it mature technology?

best regards
LC

[Electrocoolman]

Hi LC,
I can only assume they are comparing Inverter driven airconditioner against standard (non-inverter) airconditioner with a fixed speed compressor.

You would expect that sort of reduction in electricity consumption from the inverter.

[Lc_shi]

seems not, it's said to lift the power factor. who understand it?

[Electrocoolman]

Power factor of a standard non-inverter system will probably be 0.6 - 0.8. An inverter has the effect of drawing power much closer to 1.0 (unity).

Generally though, small power users will only be charged for kWh (the power meter cannot measure reactive power). It is only the larger commercial users that are penalised for drawing excessive reactive power. This is because the supply infrastructure has to be oversized to carry the TOTAL current, not just the 'real' component of the current.

[Brian_UK]

LC, is this something that you are thinking about.....

http://www.savawatt.com/

[mr cool]

ive seen those boxes before in a few supermarkets, they were afew years old and every last one had been disconnected. need i say more!

[nh3simman]

...savawatt.com

Interesting... They don't say too much about how it works.

If I compare the 3kW electric geysor to the 0.2kW fridge compressor, there is much more potential for energy savings on the hot water side.

I'm also not sure if I would like to have something messing with the power to my fridge compressor.

[Lc_shi]

There's much doubt for these saving electicity applicance. I'm puzzled how these company survive if these tech is not real. Any expert can give a last word:)

regards
LC

[Electrocoolman]

Hi LC,
Have a look at these links:

http://www.fairford.co.uk/downloads/SD0001402%20Snake%20oil.pdf

http://www.fairford.co.uk/downloads/SPOSS_EATechHiResen.pdf

What they talk about is 'optimisation' for motors where the voltage is reduced to help reduce the motor losses.
There is probably some savings, but salesmen often claim bigger savings to make their product more attractive.

ECM

[Lc_shi]

Hi ECM
It's very helpful of your material. I finally take the point. It's a tech but exaggerated by salesman:)

regards
LC