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Next Generation Ceiling Fan Motors

09/18/2010 10:29 AM

I am looking for help on the design of a next generation ceiling fan motor that can reduce energy consumption using new magnets and perhaps generate small amounts of electricity to power the radio for the remote control.

Can anyone point me in the right direction?

Regards,

Lou

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#1

Re: Next Generation Ceiling Fan Motors

09/18/2010 11:32 AM

No,

That direction doesn't exist. You can't get more energy out of a motor than energy put in. This is referred to as over-unity and will draw tons of ridicule and vitriol from this group.

Do yourself a big favor. Search "over-unity" on your favorite engine.

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#2
In reply to #1

Re: Next Generation Ceiling Fan Motors

09/18/2010 2:26 PM

Your not implying that we're unsympathetic to people's dreams are you.

Now how many little windmills does it take to run a radio, how many little windmills can one ceiling fan power ? ? ? ?

Don Quixote springs to mind

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#3
In reply to #2

Re: Next Generation Ceiling Fan Motors

09/18/2010 2:36 PM

Better still, why not use photovoltaic cells. They'd generate enough electricity for the

"small amounts of electricity to power the radio for the remote control."

At night, just shine a spotlight on the PV cells for power.

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#4

Re: Next Generation Ceiling Fan Motors

09/18/2010 3:38 PM

Ceiling fans motors are already fairly efficient in terms of power consumption. You need to consider the trade-off between the cost of the new magnets and the overall cost of the fan. You might be better-off looking into the aerodynamics of the fan blades. You might also look at techniques to minimize the blades becoming coated with dust.

Forget about 'generating' power for the remote control circuitry; it would be much more efficient to tap-off some of the 110/60 Hz power to run the controller.

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#5

Re: Next Generation Ceiling Fan Motors

09/18/2010 4:06 PM

There are gains to be had with electric motor efficiency, but they are so miniscule that nobody is pursuing them.

There are some very interesting developments currently being researched in electric motor technology, but these are all aimed at reducing weight, size and cost. This is obviously driven by automotive and mobile applications.

The size, weight, cost and efficiency of current ceiling fan motors are probably not worth trying to better (I make huge assumptions, not having too much call for ceiling fans in this neck of the woods, but if you look at cooling fans/motors over here, eg from EBM Papst (no connection on my part), to quote a highly esteemed Pythoner, "What is the bloody point?")

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#6

Re: Next Generation Ceiling Fan Motors

09/19/2010 3:11 AM

Hello,

Replace the capacitor assisted single phase induction motor in the Ceiling Fan with BLDC motor.

Rgards

Madhav Chowdhary

SWEE Technologies

(founder / owner)

Pune (India)

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#7
In reply to #6

Re: Next Generation Ceiling Fan Motors

09/19/2010 3:22 AM

Kindly give phone number, email ID etc of your set up in Pune

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#8
In reply to #7

Re: Next Generation Ceiling Fan Motors

09/19/2010 3:39 AM

Hi,

Name of the firm: SWEE Technologies

Founder / Owner: Mr. Madhav Chowdhary

Activities: Product - Systems - Project identification / conceptualization / design / development in the field of Renewable Energy / Energy Efficiency / Waste to Energy / Waste Heat Recovery

CR4 Admin - phone number and other contact info. removed

From the Site FAQ: Do not post phone numbers or email addresses. The CR4 Admin will delete all phone numbers posted in threads or comments, and we strongly urge you not to put up email addresses.

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#13
In reply to #7

Re: Next Generation Ceiling Fan Motors

09/21/2010 7:41 AM

google powerweb technologies philadelphia pa url 2powerweb lbudike

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#9

Re: Next Generation Ceiling Fan Motors

09/19/2010 10:54 AM

All ceiling fans vibrate, even on the "low" setting. You might look into installing a PZT element to generate a voltage for charging a battery in the remote controller.

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#10
In reply to #9

Re: Next Generation Ceiling Fan Motors

09/20/2010 12:23 PM

You might look into installing a PZT element to generate a voltage for charging a battery in the remote controller.

... and the remote controller would be mounted to the fan motor to recharge it? Seems to reduce the utility of a "remote" controller. Or are you thinking of using power delivery through air technology? Hand shaking the remote for a few minutes each day?

Of course, the obvious issue with mounting the PZT on the motor is that the PZT element must extract energy from the imbalance, and in doing so must slightly reduce the oscillation orbit, which in turn increases the electric load on the motor, which drives up overall cost and environmental impact. (Look at the wear pattern in the bearings and journals of an automotive balance shaft, and you can see that considerable torque is required to drive the shaft to counter the torque created by imbalance.)

To the OP:

If recharging the batteries in a remote were an issue, then perhaps solar cells, which can absorb energy for which you are not billed, would be a better bet.

Manufacturers are well aware of motor efficiency issues, and can and have done the economic trade-off analysis. More efficient motors cost more. They do the math and market research, and optimize accordingly.

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#12
In reply to #9

Re: Next Generation Ceiling Fan Motors

09/20/2010 10:01 PM

Regards.

It means old stable fans has not been ever seen now a days.

Vibrations in MODERN days is due to less weight of suspensions, higher speeds due to curves of blades in-capable of sufficient air displacement, un-balanced blades, ...

I can see still old fans in Pakistan Railways' waiting rooms, running at low speed and giving a comfortable displacement of air.

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#11

Re: Next Generation Ceiling Fan Motors

09/20/2010 6:46 PM

Thank you for all of your replies.

The basic AC ceiling fan motor utilizes approximately 75 watts of power in full operation. There are new linear DC ceiling fan motors that claim 35 watts of power during full operation. The idea is similar to a actual windmill, if we could get the fan spinning for 35 watts and somehow have the kenetic energy of the spinning blades connected to a generator could we then not generate additional power for the lights of the fan or the remote control or store the energy for DC utilization in other componets? I understand that we cant get out more than we get in but it would be a nice feature for selling the fan putting a windmill approach on it.

Lou

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#14
In reply to #11

Re: Next Generation Ceiling Fan Motors

09/22/2010 12:29 PM

The Emerson Eco is the most efficient ceiling fan on the market, and runs at 24 watts on high. Its output ranges from 620 cfm/watt on low to 289 cfm/watt on high. Another fan that claims high efficiency, but does not deliver it is the Sycamore (Uno at Dan's Fans) which was inspired by the incorrect and simplistic notion that things that look like things in nature are efficient. They advertise 110 cfm/watt, as if it is good, which it its not.

My guess is that the Emerson motor/motor control (especially motor control) is responsible for about 1/3 of the high efficiency, and that aerodynamics are responsible for the bulk -- it is one of very few ceiling fans that has had any aerodynamic thought given to the blades at all -- most blades are just boards.

The idea is similar to a actual windmill, if we could get the fan spinning for 35 watts and somehow have the kenetic energy of the spinning blades connected to a generator could we then not generate additional power for the lights of the fan or the remote control or store the energy for DC utilization in other componets?

No, this is completely wrong. The idea of a windmill is to convert wind (naturally created air motion, which is essentially free, environmentally and economically) into electricity using an apparatus that is anything but free (economically or environmetally).

Your idea, on the other hand, is to add load to the fan motor, thus increasing electrical consumption.

The power consumed by an ordinary fan is that power used to move air plus the power consumed in motor and aerodynamic losses. The slight additional power consumed (to "get the fan spinning") during startup is insignificant because startup happens so infrequently, and occurs so quickly. If, in addition to the load on the motor caused by moving air, you added the load of any generator, the overall efficiency would go down, not up.

Suppose your generator is 90% efficient, consuming (in terms of power) 1 watt to produce .9 watt to charge a battery. You have added .1 watt of losses. So, in the case of the Emerson, where you once had a fan operating at 24 watts, you now have a fan operating at 25 watts. You consumed 1 watt additional but only received .9 watts of useful power. In fact, the numbers would be much worse that this, because the generator would not be 90% efficient (nor would the battery charging circuit).

An ordinary charger will draw (for example) 1 watt to charge the battery at a rate of .8 watts, with the difference given off as waste heat. Your charger would draw 1 watt, give off .1 watt of waste heat in the generator, and then another .2 watts in the charge regulating circuit. Aside from adding cost and complexity and consuming additional resources in building these contraptions, you generate .3 watts waste where there would otherwise be .2 (and that is assuming an expensive, highly-efficient generator).

On the other hand, if you had wind blowing through your house naturally from outside, then a fan could be used (with the correct circuitry) to generate a tiny amount of electricity, if the fan were able to be placed advantageously in that airflow. However, even purpose-built windmills placed outside at optimum orientation are an expensive way to generate power.

I understand that we cant get out more than we get in but it would be a nice feature for selling the fan putting a windmill approach on it.

If you think that reducing the fan's efficiency (while implying to unsuspecting customers that the fan is more efficient) is a "nice feature for selling" then I suppose you may want to devote some time to this. Another similar possibility for bilking the public: Installing solar cells inside your house, in each room to take the light from ceiling fixtures and convert it to power that (via a boost converter and grid tie-in equipment) can be sold back to the electric company. (The cells could be built right into the ceiling fixture... a very close analogy to your idea.) A sadly large portion of the population will believe that such a system will work to their advantage, rather than to the advantage of the marketer.

I'd like to think that Emerson's approach, of actually improving efficiency is better, however.

I'd suggest that you review Post #1. Lynlynch is absolutely correct.

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