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Title: Need "Free Energy" help !
Post by: Art Welter on November 05, 2013, 03:54:19 PM
I sold my sailboat without it's solar panels and wind generator.

I use electric heat, so the contribution of up to 125 watts from solar during the day and up to 250 watts day round from the wind generator could save $5-$10 per month in heating cost.
Problem is the Air Breeze Marine generator is designed for stand-alone battery charging, and requires a minimum of 10.5 volts for it's controller to start working, otherwise the resistive load appears like an "off" switch and  "puts on the brakes", no spin, no juice.

So, without a battery, it only works when the solar panels are getting enough sun to hit 10.5 volts while loaded with a 2 ohm resistive heater,  only 8 hours a day or less this time of year, and it stops every time a cloud covers the solar panels.

I checked with Primus Windpower, who took over distribution of the generator, they said I was on my own for any solution, since I'm not using the unit as designed.

Using batteries is not an option, as when the wind dies at night the load would drain the battery, and the wind generator would not start up with a dead battery, and the battery would probably wear out from deep cycling before the cost would be recovered, even if a low voltage cut off (adding to the expense) was used. 

I tried using a small DC power supply to provide the required voltage to turn on the generator, but the load resistor dropped the voltage from 30 down to around 7 volts, too low to turn the generator on.

Any ideas how to solve the dilemma, like a low cost low output (50 milliamps would be plenty) charger that can maintain around 14 volts DC in to a very low resistance of 1-2 ohms, and won't burn out if voltage rises to 18 VDC?

Any (cheap) suggestions will be appreciated!

Thanks,
Art
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 05, 2013, 04:34:38 PM
I sold my sailboat without it's solar panels and wind generator.

I use electric heat, so the contribution of up to 125 watts from solar during the day and up to 250 watts day round from the wind generator could save $5-$10 per month in heating cost.
Problem is the Air Breeze Marine generator is designed for stand-alone battery charging, and requires a minimum of 10.5 volts for it's controller to start working, otherwise the resistive load appears like an "off" switch and  "puts on the brakes", no spin, no juice.

So, without a battery, it only works when the solar panels are getting enough sun to hit 10.5 volts while loaded with a 2 ohm resistive heater,  only 8 hours a day or less this time of year, and it stops every time a cloud covers the solar panels.

I checked with Primus Windpower, who took over distribution of the generator, they said I was on my own for any solution, since I'm not using the unit as designed.

Using batteries is not an option, as when the wind dies at night the load would drain the battery, and the wind generator would not start up with a dead battery, and the battery would probably wear out from deep cycling before the cost would be recovered, even if a low voltage cut off (adding to the expense) was used. 

I tried using a small DC power supply to provide the required voltage to turn on the generator, but the load resistor dropped the voltage from 30 down to around 7 volts, too low to turn the generator on.

Any ideas how to solve the dilemma, like a low cost low output (50 milliamps would be plenty) charger that can maintain around 14 volts DC in to a very low resistance of 1-2 ohms, and won't burn out if voltage rises to 18 VDC?

Any (cheap) suggestions will be appreciated!

Thanks,
Art
OK last first... 14 volts PS into 1-2 ohms is 7A-14A not 50 mA.
=====
It sounds like your smart regulator/battery charger is too smart to be helpful. The simplest is to grab the raw output from the alternator (AC) and dump that directly into your 2 ohm load... This will suck whatever power the wind turbine is making into the heater.

This AC voltage may not coexist with the solar panel DC output. Power rectifiers could convert the alternator AC into DC so they could be summed together and not drive into each other (diodes in series with both). These diodes will waste a little power, but that waste heat will go into your room too so no loss really. Simplest approach is separate heat coils, but 1-2 ohm seems unusual.

The cheap plug in room heaters are more like tens of ohms.

JR

PS: I have done some messing around with microprocessor control of heating, You can use simple diodes to measure room temperature by the voltage drop across them. With a triac  you could let a microprocessor turn your green heater on and off...


   
Title: Re: Need "Free Energy" help !
Post by: Mike Christy on November 05, 2013, 05:57:12 PM
Hi Art,

Can you get into the circuit board? My thoughts are if you can find and figure out the circuit ( maybe its just a zener diode and divider network ) that is providing the micro with the OK to go signal at 10.5V, you could isolate that from the main + output, and apply your own 10.5VDC - even with a wallwart.

Ye ole reverse engineering...

Mike
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 05, 2013, 06:24:54 PM
OK last first... 14 volts PS into 1-2 ohms is 7A-14A not 50 mA.
=====
 The simplest is to grab the raw output from the alternator (AC) and dump that directly into your 2 ohm load... This will suck whatever power the wind turbine is making into the heater.
JR, Mike,

I was thinking there might be a type of PSU that could put pulsed DC in that would not require much average amperage. But pulsed DC might not fool the control circuit in to thinking a "real" 10.5 V was present.

I don't want to modify the Air Breeze, as the "brain" keeps it from over-running in high winds.
To apply DC directly would require mounting a battery inside the unit, a wall wart would get hopelessly tangled, as you can watch the wind rotate through 360 degrees, sometimes in a manner of minutes.
At any rate, it is up 21 feet in the air, and was not too easy to erect even with a helper- I remember why I only set it up once on my boat...

I do have a RS Micronta 12V 8 amp power supply (13.8 v actual), and a 10 amp (semi-smart) battery charger. Both are heavy transformer based units.
Couldn't find any schematics for the Micronta, but it does not say "regulated" as some of the units do. Does have a circuit breaker in back.

The Micronta lives in a very convenient place for hook up, and is normally on 24/7 already (shop stereo) do you think it would be safe combined with the variable output (0-17 volts) of the panels and generator ?

P.S.- tried the 10 amp battery charger, it was able to deliver 9.8 volts in to the 2 ohm load, looks like a  charger with 50 amp start feature might do the trick.

Art
Title: Re: Need "Free Energy" help !
Post by: Tom Bourke on November 05, 2013, 11:38:20 PM
JR, Mike,

I was thinking there might be a type of PSU that could put pulsed DC in that would not require much average amperage. But pulsed DC might not fool the control circuit in to thinking a "real" 10.5 V was present.

I don't want to modify the Air Breeze, as the "brain" keeps it from over-running in high winds.
To apply DC directly would require mounting a battery inside the unit, a wall wart would get hopelessly tangled, as you can watch the wind rotate through 360 degrees, sometimes in a manner of minutes.
At any rate, it is up 21 feet in the air, and was not too easy to erect even with a helper- I remember why I only set it up once on my boat...

I do have a RS Micronta 12V 8 amp power supply (13.8 v actual), and a 10 amp (semi-smart) battery charger. Both are heavy transformer based units.
Couldn't find any schematics for the Micronta, but it does not say "regulated" as some of the units do. Does have a circuit breaker in back.

The Micronta lives in a very convenient place for hook up, and is normally on 24/7 already (shop stereo) do you think it would be safe combined with the variable output (0-17 volts) of the panels and generator ?

P.S.- tried the 10 amp battery charger, it was able to deliver 9.8 volts in to the 2 ohm load, looks like a  charger with 50 amp start feature might do the trick.

Art
I think having to use such a powerful supply just to keep it active will cost you more in electrical use than your saving.  The charger would be driving the heater 24/7 using full draw from the outlet.  You would be much better off replacing some other electrical usage with your wind or solar unit.  One candidate is your stereo  another is lighting.
Title: Re: Need "Free Energy" help !
Post by: Bob Leonard on November 06, 2013, 12:39:49 AM
I agree with Tom. What you're finding is the reason solar panels or wind just aren't as popular as many people think. The solutions for realistic savings quite often cost more than the process they replace.

In all honesty you could probably benefit by using the wind and solar power to charge a battery bank, which could then feed an inverter.

I also don't know where you live Art, but people here in the northeast stay far away from electric heat as much as possible. It's just too damned expensive. If it were me I would replace the electric heating elements with a forced hot water system and install a small 100,000 BTU gas or oil fired boiler. You could even use a tankless boiler mounted water heater and that alone may recover the cost you hope to recover with by using the wind and solar solution you have.
Title: Re: Need "Free Energy" help !
Post by: Tim McCulloch on November 06, 2013, 01:01:07 AM
Art is in New Mexico.
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 06, 2013, 01:08:26 AM
I would be apprehensive about second guessing how to fool the turbine controller into working.

If over revving, with a load attached is a real concern, maybe add some more load on a windy night.

I am all in favor of green science fair projects, I do some myself.

@Bob re: electric heat up north, I rented a condo outside Hartford with electric hot water and it was nicer than the typical oil burner, but indeed resistance heat is more expensive. Luckily for me that was in the '80s not now.   

Living in the deep south I understand resistance heat... About a year ago I replaced my big in wall air conditioner with a combo conditioner/heat pump, so now I'm making heat with roughly 1/3 the electricity. Try that up in MA :-) Bad news is they are building a coal electric plant near me, and my electricity rate has already gone up 15% to cover cost over runs, and it isn't even making electricity yet. Yup, clean coal... what could go wrong?

JR
Title: Re: Need "Free Energy" help !
Post by: John Fruits on November 06, 2013, 06:00:46 AM
Might I suggest another forum which might be helpful?
countryplans.com
This website is about affordable plans for simple, owner built homes, with lots of focus on pay as you go, no mortgage living.  The forums have some great people who know what they are talking about.  There is quite a bit about alternate energy and living off grid.  The forums are very active and lots of tinkerers there. 
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 06, 2013, 10:16:52 AM
Might I suggest another forum which might be helpful?
countryplans.com
That site has lots of useful information, but what I am trying to accomplish is not normal for them- any solar wind generator system would normally be used in conjunction with batteries, which for my on grid use are not warranted or desirable.
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 06, 2013, 12:21:06 PM
That site has lots of useful information, but what I am trying to accomplish is not normal for them- any solar wind generator system would normally be used in conjunction with batteries, which for my on grid use are not warranted or desirable.

OK, you have a glorified battery charger. That manages itself when battery voltage gets too high.

You could use several rechargeable D cells to trick that part of it, and then you need to be able to disconnect the load when generation is not able to maintain battery voltage above some minimal voltage level.

Not rocket science but you need a decent current capability switch and ability to compare voltage to an on/off threshold. You might not even need a battery, a large enough capacitor might be enough to smooth out the alternator current pulses. In fact with a large capacitor instead of battery it wouldn't be damaged by low voltage so, no wind, no heat, no problem. 

I would be tempted to also add a temperature sense to disconnect heat when not needed but a simple mechanical switch can do that.

What happens if you just connect the load to the system with no battery?

JR

Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 06, 2013, 12:55:28 PM
OK, you have a glorified battery charger. That manages itself when battery voltage gets too high.

You could use several rechargeable D cells to trick that part of it, and then you need to be able to disconnect the load when generation is not able to maintain battery voltage above some minimal voltage level.

Not rocket science but you need a decent current capability switch and ability to compare voltage to an on/off threshold. You might not even need a battery, a large enough capacitor might be enough to smooth out the alternator current pulses. In fact with a large capacitor instead of battery it wouldn't be damaged by low voltage so, no wind, no heat, no problem. 

I would be tempted to also add a temperature sense to disconnect heat when not needed but a simple mechanical switch can do that.

What happens if you just connect the load to the system with no battery?

JR
As I explained in the OP, if the load is connected to the system with no battery the generator only works when the solar panels are getting enough sun to hit 10.5 volts while loaded with a 2 ohm resistive heater,  only 8 hours a day or less this time of year, and it stops every time a cloud covers the solar panels.
The  generator requires a minimum of 10.5 volts for it's controller to start working, otherwise the resistive load appears like an "off" switch and  "puts on the brakes", no spin, no juice.

The solution you mention is viable and available commercially for around $150 not including batteries (but the batteries would be shot long before the energy production would pay for the expense, been there, done that)  but require far more design expertise than I have to make myself.

Still looking like a car battery charger with slightly more than 10 amp charge capacity will do what is needed for the cheapest cost, my 10 amp charger came within a volt of the turn on voltage required by the generator, a charger with a "start" feature should handle the resistive load.
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 06, 2013, 01:25:54 PM
Just to be clear, is the 10A battery charger just to start the generator working and wind can hold the load up after started, or must the load be getting 10+ amps continuously for the wind generator to add on top of that?

If the battery charger must put out that much current continuously it may not be designed to do that so could also fail prematurely from over heating.

We come full circle. I would consider working around that regulator that is only happy charging a battery, or connect a battery but that still requires a load disconnect when battery voltage gets low.   

Good luck

JR
Title: Re: "Free Energy" Help!
Post by: Russ Davis on November 06, 2013, 02:01:02 PM
Using batteries is not an option, as when the wind dies at night the load would drain the battery...

Maybe I'm missing something, but wouldn't a simple blocking diode solve this?  Even cheap solar kits include them, to prevent current from flowing back from the batteries at night.
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 06, 2013, 02:15:10 PM
Just to be clear, is the 10A battery charger just to start the generator working and wind can hold the load up after started, or must the load be getting 10+ amps continuously for the wind generator to add on top of that?

JR
The battery charger (or solar panels) must be capable of providing 10.5 volts in to the 2 ohm load or the wind generator (which is connected to that load) won't start up.
My 10 amp charger was not able to do that, it only could do 9.8 volts, so I'm looking at a more robust charger with motor start capability, which should not mind seeing a very low resistance.

Once the wind generator starts up, it would provides  power to the load, the charger would see around 13 volts and go to trickle charging.

The question is whether a motor start type charger will hold up to providing around 95 watts continuous when the wind stops blowing at night. The 10 amp charger I have seemed to be OK (other than bogging down to 9.8V) so I think a more heavy duty charger should do the trick.

I'm heading off to Harbor Freight now with some resistors and voltmeter to test my theory..
Title: Re: "Free Energy" Help!
Post by: Art Welter on November 06, 2013, 02:22:55 PM
Maybe I'm missing something, but wouldn't a simple blocking diode solve this?  Even cheap solar kits include them, to prevent current from flowing back from the batteries at night.
Diodes prevent the solar panels from being a load at night, but I need the load connected to the wind generator, which needs 10.5 volts to turn on.

10.5 volts is what a 12V battery reads when completely dead, which is what it would be after a short period of time connected to the 2 ohm load resistor without power being generated by wind or solar.
Title: Re: Need "Free Energy" help !
Post by: Jonathan Johnson on November 07, 2013, 02:12:44 AM
I'm imagining a separate anemometer that connects the battery to the system when the wind speed exceeds a certain threshold, thereby activating the turbine. When wind speed drops below the threshold, the battery is disconnected.
Title: Re: "Free Energy" Help!
Post by: Mike Christy on November 07, 2013, 05:37:38 AM
Seems like what you need Art s a relay to open the load ( the heater ) from the battery when the turbine isnt turning (no wind).

Attach a cheap deep cycle battery as normal, attach the heater across it as normal, then gin up some way to sense when the gen is charging - those status LEDs and a photo sensor possibly, or just a comparator circuit to sense higher than dead battery voltage, open the load relay when the turbine isnt turning.

So in essence the heater only works when the turbine is turning.

Maybe?
Title: Re: "Free Energy" Help!
Post by: Art Welter on November 07, 2013, 09:48:14 AM
Seems like what you need Art s a relay to open the load ( the heater ) from the battery when the turbine isnt turning (no wind).

Attach a cheap deep cycle battery as normal, attach the heater across it as normal, then gin up some way to sense when the gen is charging - those status LEDs and a photo sensor possibly, or just a comparator circuit to sense higher than dead battery voltage, open the load relay when the turbine isnt turning.

So in essence the heater only works when the turbine is turning.

Maybe?

Again, the solution you mention is viable and available commercially for around $150 not including batteries (but the batteries would be shot long before the energy production would pay for the expense, been there, done that)  and requires more design expertise than I have to "gin up" myself.

Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 07, 2013, 10:40:27 AM
I'll try not to repeat myself but lets look at the power math.  125watts from solar, and 250watts from wind "day round" (peak, ave, other?). You suggest a load of 1-2 ohms. A voltage range of  10.5V min for regulator operation, max V of 18V(?).

FWIW 18V is only 325W into 1 ohm load so if power output is capable of 18V that sounds ballpark.

If an external (hard) 10.5V power supply has a steering diode in series with it's (11+v) output, it can supply current only when the solar and wind is not. Once the solar and wind is putting out more than 10.5 amps at 10.5 volts, the power supply diode will stop conducting and the load is completely driven by green energy. 

The way (cheap) battery chargers are designed is to provide a "soft" voltage supply higher than 12V. For example a 13.5V hard voltage source with say 0.2 ohm in series. At 10.5V that is 15A draw, at 12.5V 5A, at 13.5 0A. As the battery charges up the current draw naturally drops off, so connected as you suggest, at 10.5V the battery charger is putting the full 105W into the load. As the solar/wind output rises, the contribution from the charger drops off as the power into the load increases, but for a typical battery charger it will still be supplying some power all the way up to 13-14V

So this will work, IF you can find a charger that is happy to put out over 10 amps, perhaps for some significant time duration if left on when green energy is not producing at least 100W. If you can't find a battery charger that works, I would look for a dedicated say 11V (12V may be more common) 10+ amp power supply then add an output steering diode. You will lose at least a 1/2 V more like 3/4 from the steering diode, so  12V nominal is not crazy. (note: this is not a small diode and it will need a heatsink to dissipate a few watts itself.)

A simple(?) thermostat could turn this power supply on/off when inside temp is above target, while it might make sense to heat up a hot water tank or find some way to hold excess energy captured. 

Have fun...

JR

 
 
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 07, 2013, 11:57:26 AM
125watts from solar, and 250watts from wind "day round" (peak, ave, other?). You suggest a load of 1-2 ohms. A voltage range of  10.5V min for regulator operation, max V of 18V(?).

FWIW 18V is only 325W into 1 ohm load so if power output is capable of 18V that sounds ballpark.

If an external (hard) 10.5V power supply has a steering diode in series with it's (11+v) output, it can supply current only when the solar and wind is not. Once the solar and wind is putting out more than 10.5 amps at 10.5 volts, the power supply diode will stop conducting and the load is completely driven by green energy. 


JR
Yes, 18V is 325W into a 1 ohm load, which is why I am presently using a 2 Ohm load for the 125 watt (peak) solar panels. When the generator kicks in and raises voltage to around 17, the 2 ohm load is dissipating around 144.5 watts. Panels no load go to around 20 V, but with  max sun in to 2 ohms they do about 14.5, when the generator kicks in with screaming wind it can hit 17 V (in addition to the panels), which is it's limit on paper.
An "unobtanium" load that would start at around 100 ohms at 10.5 volts and drop to 1 ohm at 17 volts would be ideal.

The wind generator is really variable, it would only put out 250 watts at 25 MPH, but regulates to 200w at speeds above.
Takes almost 18MPH to do 100 watts. At 10 MPH, it only does about 20 watts.
Only 38kW, about $4 worth of energy per month at 12 MPH average wind speed.

You answered the question I posed in #3, if I get what you are saying, my Micronta 13.8 V 8 amp PSU should be safe to drive the load and not be damaged by the higher voltage from the panel and generator if it goes through a beefy diode.

Would you suggest using a diode on both the + and - of the PSU, or is one on the + sufficient?

Thanks,
Art
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 07, 2013, 01:08:43 PM
You only need one diode with anode toward PS and cathode toward load. If that PS is adjustable you could extract more energy from solar panel by dialing down closer to 10.5V min. You could stack some diodes in series with 13.8V supply, while diodes would get hot from extra watts of dissipation, they would more efficiently extract solar power.

A little rube goldberg, but a temperature switch on the diode heat sink could detect when heater is running from PS only based on heatsink temp and cut it off. Unfortunately these are generally self resetting so it would cycle itself to death. A resettable circuit breaker in series with power supply might work if sized properly. It needs to hang long enough to start system, or you could use a start switch that bypasses the breaker to start. Of course resettable breakers are not rated for lots of cycles either, but this would be low tech solution. The diode(s) would be dissipating several watts max so enough heat to heat up a small heatsink. 

====
You could actually chop the load with a HF switch (like mosfet) to make it appear like a lighter load at low voltage.  At 50% duty cycle 1 ohm looks like 2 ohm, etc. That is the technology behind that speaker protection add on gadget, it scuibs power away from speakers by duty cycling the AC voltage fed to the speaker driver. Of course you would have to roll your own controller. About $10 parts, but way too much design effort for a one off. Of course you could roll a thermostat and time of day controller into this load controller making it slicker than snot on a doorknob.  or not...

JR
 
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 07, 2013, 02:15:24 PM
You only need one diode with anode toward PS and cathode toward load. If that PS is adjustable you could extract more energy from solar panel by dialing down closer to 10.5V min. You could stack some diodes in series with 13.8V supply, while diodes would get hot from extra watts of dissipation, they would more efficiently extract solar power.
A little rube goldberg, but a temperature switch on the diode heat sink could detect when heater is running from PS only based on heatsink temp and cut it off.

You could actually chop the load with a HF switch (like mosfet) to make it appear like a lighter load at low voltage.  At 50% duty cycle 1 ohm looks like 2 ohm, etc.  About $10 parts, but way too much design effort for a one off.
JR
The "free" power is only providing a portion of the heating needs, so if the PSU is doing the heating when the sun and wind aren't, no problem.

If you feel like designing the load chopper, I'll pay you 3 months worth of the energy cost it saves  ;).

Thanks for the tips, off to Radio Shack for some Schottkys.
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 07, 2013, 02:54:08 PM
The "free" power is only providing a portion of the heating needs, so if the PSU is doing the heating when the sun and wind aren't, no problem.
or the diodes getting hot :-)
Quote
If you feel like designing the load chopper, I'll pay you 3 months worth of the energy cost it saves  ;).
I have designed my own DIY heat gadget but that's different...
Quote
Thanks for the tips, off to Radio Shack for some Schottkys.
Schottkeys are metal junction low forward drop diodes. For your application the more drop the better (I'd be tempted to throw a few in series ) something like a power supply diode bridge can be wired as two diodes in series and is easy to heatsink.

JR
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 07, 2013, 08:02:14 PM
Schottkeys are metal junction low forward drop diodes. For your application the more drop the better (I'd be tempted to throw a few in series ) something like a power supply diode bridge can be wired as two diodes in series and is easy to heatsink.
Well, RS does not carry Schottkys or high powered diodes, so I'll be using four 3 amps in parallel (all they had, I thought of what you said about series, and went back for more, the cupboard was bare)..



Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 07, 2013, 11:51:38 PM
Well, RS does not carry Schottkys or high powered diodes, so I'll be using four 3 amps in parallel (all they had, I thought of what you said about series, and went back for more, the cupboard was bare)..

Not to ruin your fun but diodes in parallel will not share nicely... the hotter diode will have a lower forward voltage so get a larger share of the current, making it hotter, causing the forward voltage to drop more, you can imaging how this ends (melted silicon).

The technical term for making parallel diodes, or whatever share, is to use "degeneration" resistors, something like .1 or ,22  ohm in series with each diode will swamp out the bad sharing behavior caused by temperature coefficient.  A .1 or .22 ohm will also drop some more voltage which is a good thing in your case.

I would still use a !0a diode bridge or something like that, two diode drops in series.   

JR
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 08, 2013, 07:06:40 PM
Not to ruin your fun but diodes in parallel will not share nicely... the hotter diode will have a lower forward voltage so get a larger share of the current, making it hotter, causing the forward voltage to drop more, you can imaging how this ends (melted silicon).
So far the diodes in parallel seem OK, hot to the touch but well under 212 F.
The RS PSU also seems OK powering the  2 Ohm load through the diodes, voltage is holding at about 11.8 after dark. No wind, of course- seems the wind has been far less ever since i put up the generator...
The loaded PSU makes a bit of noise in the stereo, but that goes away when the sun shines  :).
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 08, 2013, 09:44:53 PM
The old spit test for 100'C is OK, silicon doesn't melt until well above 150' C while some plastic packages degrade before the junction melts.  If all the parallel diodes are roughly the same temp they are matched well enough.

JR
Title: Re: Need "Free Energy" help !
Post by: Art Welter on November 09, 2013, 01:44:53 PM
The old spit test for 100'C is OK, silicon doesn't melt until well above 150' C while some plastic packages degrade before the junction melts.  If all the parallel diodes are roughly the same temp they are matched well enough.
JR,

Well, the epoxy diodes lasted the night, and all still seem the same temperature.

At the present wind velocities, the $4 diode investment should pay for itself by the end of the winter season ::) .

Thanks for the help, the goal of little expenditure (for a little gain) has been achieved!

Art
Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 09, 2013, 02:22:57 PM
JR,

Well, the epoxy diodes lasted the night, and all still seem the same temperature.

At the present wind velocities, the $4 diode investment should pay for itself by the end of the winter season ::) .

Thanks for the help, the goal of little expenditure (for a little gain) has been achieved!

Art
So you don't want to pay me $100Hr to design up a custom gadget for you... ?

You could squeak out a little more green energy by adding those resistors in series with the diodes. As long as it still makes enough voltage to just turn on the regulator you get that extra low output solar and wind. Resistors should be cheap while the gains will be marginal, but real.

Of course you are not billing for your time either.

JR

PS: I just tweaked my DIY smart electric heater. I was using a very old auxiliary electric heater, connected to my smart controller. The old 650W heater came with my house, so it was old 30 years ago.  It still makes heat, I had to replace the on/off switch that crapped out maybe 15 years ago, but my complaint is that the heating wires sing and rattle when the are heating up. Not a loud noise, but loud enough in a quiet bedroom in the middle of the night. I tweaked my heater to duty cycle 20%, 40%, 60%, 80% or full on based on how far below the threshold temp it was. This knocked down the old heater noise by a similar fraction. So I decided to see what modern technology has to offer. The cheapest wallmart aux heater, for $19.95 makes 2x the heat, has a fan blower, and a thermostat. Better yet it has a tilt safety switch and thermal overload fuse, so safer too.  The new heater doesn't  make any wire rattling noise, but the fan motor didn't like the 20% speed. It thumped at like 30Hz, so I added 150 ohms in series with the motor, that quieted it down and slowed it down at max heat... I now have twice the heat if/when I need it, and silent running. 
Title: Re: Need "Free Energy" help !
Post by: Craig Hauber on November 11, 2013, 08:12:29 PM
The old 650W heater

Here in ND, 650W is not really considered a "heater" :-)

6500W might be a good start though.

(yes, yes I know, I'm wondering why people actually live here too.)

Title: Re: Need "Free Energy" help !
Post by: John Roberts {JR} on November 11, 2013, 08:33:27 PM
It depends on how much heat you are losing to the outside.

The math is the difference between inside temp and out side temp "times" the thermal resistance from inside to outside. So temperature delta and rate of loss both affect how much heat you need to replace. 

My new cheapest heater is 1300W and barely runs at more than 20% to keep up... but it isn't really cold yet.

JR
Title: "Free Energy" update
Post by: Art Welter on December 12, 2013, 12:11:53 PM
Using a 12 volt power supply through diodes made the wind generator function, from 11/7/13 through December 12/4/13  :'(.
Noticed some extreme gusts that day, and that the generator was no longer spinning around dusk, even though the wind was blowing strongly.
Snow fell the next morning and a few times since, but had melted to the point where I felt OK climbing up to check out the generator yesterday.

Evidently the electronics failed, allowing the generator to spin fast enough for 7 out of 12 magnets on the rotor to break off and jam in the gap between the stator. Surprisingly there seems to be no damage to the stator, and little damage to any of the magnets.
I can probably fix the magnets back on the rotor with some glue, but will have to replace the electronics.

The replacement will probably cost more than the equivalent value of the electricity the generator could produce over several years.

Considering the generator only operated less than 5 weeks (<2 weeks boat use, <3 weeks heating use) makes me wonder weather it is worth the bother...

Art
Title: Re: "Free Energy" update
Post by: John Roberts {JR} on December 12, 2013, 12:51:43 PM


Evidently the electronics failed, allowing the generator to spin fast enough for 7 out of 12 magnets on the rotor to break off and jam in the gap between the stator. Surprisingly there seems to be no damage to the stator, and little damage to any of the magnets.
I can probably fix the magnets back on the rotor with some glue, but will have to replace the electronics.

The replacement will probably cost more than the equivalent value of the electricity the generator could produce over several years.

Considering the generator only operated less than 5 weeks (<2 weeks boat use, <3 weeks heating use) makes me wonder weather it is worth the bother...

Art

I would have been tempted to roll my own controller from the start... but different strokes.

Is there any way to better secure the magnets to survive higher RPM and more power output? Glue seems questionable, can't use ferrous metal, some combination of dynamic loading and more robust attachment.

My DIY project has progressed on two fronts. My cheapo $20 heater while making more watts, had a fan so was noisy in a different way, and when I tried to tweak it to be be quiet it overheated, so back to the drawing board.

I found a proper 1kW baseboard heater that would run on 120V most are 240V, So now I have a silent heat unit. My back of the envelope calculation was that the extra heat output would only buy me some 6' more temp capability, but at the same time I upgraded my "red neck" storm windows. House was built with typical for the deep south single pane glass windows with permanent screens. My red-neck storms were sheets of drop cloth plastic stapled to the inner window frame. THe upgrade was to build some wood frames from 1"x2"  pine, that nests inside the window frame/sill. I then covered both sides of these frames with clear window film (variation on saran wrap). With the new improved "Beverly Hillbilly" storm windows I capture two insulating pockets of still air between the outer window glass and inner room air. Between the increased heat output and reduced heat loss from windows, my small 1kW aux heater has been able to hold inside temperature regulation with outside temps at night in the low 20's. It takes a couple hours at night to heat up the thermal mass of the room interior (walls etc)  that cools down to probably 50's during the daytime with all heat turned off.

JR

PS: I expect to break even within one heating season for the new improved storm window treatment, if I ignore my labor cost. I did several windows around the house including a 4'x8' picture window that was single pane and uncovered except for drapes.

PPS: The feds have started granting waivers for commercial windmills killing protected species birds. Once again their execution of the law seems to bend with their different agendas. I think they were offering 20 year permits or something like that.   
Title: Re: Need "Free Energy" help !
Post by: Bob Leonard on December 12, 2013, 02:04:13 PM
That sucks Art, lots of work for not much benefit. I had a similar problem with an 18HP Briggs where the magnets flew of the rotor/flywheel, jammed the flywheel and the engine wouldn't start. I rebuilt the engine that summer and it's been running like a champ ever since.
Title: Re: "Free Energy" update
Post by: Art Welter on December 12, 2013, 02:22:54 PM
I would have been tempted to roll my own controller from the start... but different strokes.

Is there any way to better secure the magnets to survive higher RPM and more power output? Glue seems questionable, can't use ferrous metal, some combination of dynamic loading and more robust attachment.

My DIY project has progressed on two fronts. My cheapo $20 heater while making more watts, had a fan so was noisy in a different way, and when I tried to tweak it to be be quiet it overheated, so back to the drawing board.

I found a proper 1kW baseboard heater that would run on 120V most are 240V, So now I have a silent heat unit. My back of the envelope calculation was that the extra heat output would only buy me some 6' more temp capability, but at the same time I upgraded my "red neck" storm windows. House was built with typical for the deep south single pane glass windows with permanent screens. My red-neck storms were sheets of drop cloth plastic stapled to the inner window frame. THe upgrade was to build some wood frames from 1"x2"  pine, that nests inside the window frame/sill. I then covered both sides of these frames with clear window film (variation on saran wrap). With the new improved "Beverly Hillbilly" storm windows I capture two insulating pockets of still air between the outer window glass and inner room air.
If the electronics were working properly, the RPM would have been controlled.
If the magnets had not fell off and jammed, the carbon fiber blade attachment probably would have been the point of failure, and would have departed at the hub around mach 1, which could be quite dangerous.
It does surprise me that 7 out of 12 magnets fell off before it locked up.

I had used two single pane windows with an air space between on my house to begin with, there were enough old 6 and 9 pane frames that were laying around on the property to double up on as much glass as I wanted.
The problem with the "red neck" solutions is small air leaks add up to rather large differences in thermal efficiency.

After Bonnie moved in, about 4 years ago we upgraded to Pella windows, as the dual single pane sandwich were really hard to open and shut, and the screens around the hardware had gaps requiring rags..

The weather varies so much it is hard to say how much more efficient the new Pella windows are than the old, but if quietness is a measure, the change is quite apparent.

I left one  "redneck doublepane" in the (unheated) laundry room, it surprises me now when I go in there and can hear typical road noise, while the rest of the windows are so air-tight it takes a bunch of Harleys to hear.
Title: Re: Need "Free Energy" help !
Post by: Art Welter on December 12, 2013, 02:41:19 PM
That sucks Art, lots of work for not much benefit. I had a similar problem with an 18HP Briggs where the magnets flew of the rotor/flywheel, jammed the flywheel and the engine wouldn't start. I rebuilt the engine that summer and it's been running like a champ ever since.
At least my problem did not involve getting soaked or loss of tubes!

Found the guest house water heating element failed just before some holiday guests came, but since I did not find out about it until after filling the tank (a day before they arrived), have not fixed it yet, though will soon.
While purchasing the heating element I considered putting in some valves so the hot water tank would not have to be filled and then drained for short duration winter use, as the guest house uses water catchment with only a 160 gallon reserve, so loosing 25 gallons is of some concern.
I leave it unheated when not in use, and draining the hot water tank requires crawling under the house and hooking on a drainage hose..

After remembering your Thanksgiving fiasco with valves (and some of my own) decided I will live with the present arrangement  ;).