03-09-14, 09:16 PM | #1 |
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Efficiency of DC ceiling fans?
Have been see in a lot of talk about the energy savings of ceiling fans with DC motors. Do they really save that much electricity or is it spin?
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03-09-14, 09:29 PM | #2 |
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ECM is a lot more efficient than induction for multi speed fan motors. The very nature of making an induction motor multi speed (without an inverter) greatly drops efficiency.
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03-10-14, 05:02 PM | #3 |
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03-10-14, 05:18 PM | #4 |
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Pretty sure those values are for shaded pole motors. Even the cheap PSC motors do a lot better than 12%, maybe 60% for a bad one. In contrast, ECM easily does 80% or more.
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03-10-14, 07:51 PM | #5 |
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I'm just sayin' the average $50 ceiling fan is not real efficient. A $180 Brushless DC model might use a third of the power at the same speed. The flat, oar-shaped blades don't help out either. That being said, ceiling fans don't use that much power unless you don't turn them off when you leave the area. A fan not running uses no energy.
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03-10-14, 08:33 PM | #6 |
Steve Hull
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Interesting discussion as we have several ceiling fans that are on a LOT in the summer. I had honestly not thought of the DC motor fans as that much more efficient. Dumb me as I am certainly aware of the impact DC motors have on furnace fan performance.
Now to the point - which specific ECM ceiling fans are the best buy? I need to buy a new one. Steve
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03-10-14, 08:58 PM | #7 |
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03-17-14, 06:11 AM | #8 |
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296 CFM per watt, but fan will set you back $300. Really would like to see LED light kit as an option on this.
Last edited by Servicetech; 03-17-14 at 06:15 AM.. |
03-17-14, 08:42 AM | #9 |
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Maybe it's possible to DIY a ceiling fan out of an ECM HVAC motor and a condenser fan blade? Probably won't be particularly cheap unless you can get a "bad" motor and repair it...
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03-17-14, 09:00 PM | #10 |
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Would fail the WAF test. Wouldn't be the safest thing in the world either.
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