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View Full Version : I have a solar panel !



A.K. Boomer
11-30-2012, 10:26 AM
I know - it's just one but Im still very excited about it - my generous older bro gave it too me as he replaced a bunch that were hit by lightening and some survived and some were toast.

so - here's the thing - it's just a one panel BP 170 watt and im thinking of all the possibilities that I can do with just one panel...

Here's what I come up with for the biggest bang for the buck as to how it will help me reduce my overall bills both electric and gas...

Let me first say that I live in an area that catches allot of sun, let me also state that I took the panel out in the sun yesterday and connected it to a V/6 ford Tuarus electric rad. fan and Wow! it wasn't quite like it was hooked up to a car but that baby was pushing some air....

and that's what I plan on doing with it - in the winter it will draw pre-heated air (most likely from the peak of the roof under eve in front of the house on the south side) from a blacked out area that I double pane and insulate, and then pump it to the "cold end" of the house with insulated duct in the attic, I think it should have enough grunt to get the job done, the Taurus fan is about 12" ! and I bet I can use a very efficient 6" and gain allot of pressure...

Then, in the summer I will flip a switch and the current will go to another lower RPM but high volume attic fan that will pump air from the house into the attic --- this will keep the attic cooler - I do this anyways because I have a swamp cooler and need a place to dump all the incoming cool air so that the swamper can "breath" when it's running...

Iv just been leaving the attic access door open and use the swamper motor to do the work and it works out great - vents through the eve vents and not only reduces the time the swamper has to run by keeping the attic cooler but also increases roofing shingle life...

So, the panel will be benefiting mostly all year round, In the winter it will slightly reduce both electric and gas usage due to the furnace running less,
and in the summer it will reduce the time the swamper has to run (it's on a thermostat)
and this will reduce electricity use - I will even have the option of using the swamper on just "pump" mode - so the aspen pads keep soaked whilst they are under a slight draw just from the solar attic fan - this will further reduce "real run time", the panel getting power from the sun happens for the most part as soon as the house needs cooling,

both summer and winter modes will be 100% maintenance free, set it and forget it - it will help as much as it can and that's that,

I can't think of a better more efficient way of using just one panel than for pushing "virtually free" heated or cooled air around to where you want and need it...

but - if anyone else has a better Idea im all ears...

what would You do with just one panel?

flylo
11-30-2012, 10:46 AM
Have you checked the temp at the peak inside the attic? Might be the place to get the warm air you need the just reverse polarity in the summer. Just a thought.

A.K. Boomer
11-30-2012, 10:54 AM
Yes - well no - have not checked the temp but thought about it and my bro also mentioned it - I have fiberglass insulation and don't want to take the chance of pumping that into the house, could install a box up there with a furnace filter or two - but - attics have kinda a dis-stink-tive odor from dealing with all the heat, yet - my roof is a darker color and it does get toasty up there but not to the extent that a special designed place would and nowhere near as quickly...

still - that's the type of thinking I like so thank you...

Weston Bye
11-30-2012, 12:51 PM
I knew a fellow who inherited the water power rights to a local millpond and had a Pelton wheel generator connected. The trouble was that he also posessed a collossal ration of invincible and determined ignorance concerning the efficient application of the resource at his disposal. The best that he ever achieved was to power a set of infared heating panels in his basement during the winter to supplement the power he was buying from the local utility.

Evan
11-30-2012, 01:59 PM
Use it to run LED lighting. Charge a battery during the day and relax in the evening with stored sunshine.

The Artful Bodger
11-30-2012, 02:08 PM
I knew a fellow who inherited the water power rights to a local millpond and had a Pelton wheel generator connected. The trouble was that he also posessed a collossal ration of invincible and determined ignorance concerning the efficient application of the resource at his disposal. The best that he ever achieved was to power a set of infared heating panels in his basement during the winter to supplement the power he was buying from the local utility.


Pelton wheel on a mill pond? I can see how that might be a problem.

The Artful Bodger
11-30-2012, 02:19 PM
Hi Mr Boomer, we have a roof space heat recovery system in our house. The roof space is not insulated, the ceilings are but the steel roof is the heat collector and heats the roof space to 50C+ (which is quite toasty).

The roof space heats quicker than the house in the morning so warmed air is pushed down by a fan (two 80 watt fans for a 200 sq metre house) until the house is up to temperature. The roof cools quicker too so after a hot day the cool air from the roof space is used to cool the house.

Air from the roof space has to be filtered or the house suffers from dust.

Thats how our system works, it does contribute to heating and cooling and it ventilates the house with filtered air.

BTW, in our climate we use very little heating and almost no cooling.

Weston Bye
11-30-2012, 02:39 PM
Pelton wheel on a mill pond? I can see how that might be a problem.

The mill pond wasn't the problem. It was a very large pond with about 25 feet of head to the turbine. The pond was originally used to power a flour mill using a tub wheel.

The problem was the fellows' lack of ambition to harness and use the power efficiently.

Evan
11-30-2012, 02:43 PM
25 feet is barely enough to run a pelton wheel. I have a friend that runs one with 800 feet of head. Even a very small wheel can generate quite a few kilowatts with that head. It's limited only by the penstock diameter.

Weston Bye
11-30-2012, 02:52 PM
'Twas good enough for several kilowatts, but he only ever used it for heat.

sasquatch
11-30-2012, 06:52 PM
Congrats on the 170watt pannel!! You are going to have fun with that, i can tell from your'e post!!

You'll be comming up with other uses for it also i'm sure!! Lol

1-800miner
11-30-2012, 07:25 PM
You are going to cook the fan from low voltage on cloudy days as well as sun rise and sunset.
I speak from experience.
Google up a linear current booster. Install it between fan and panel and you are good to go.

owl
11-30-2012, 08:03 PM
Yes - well no - have not checked the temp but thought about it and my bro also mentioned it - I have fiberglass insulation and don't want to take the chance of pumping that into the house, could install a box up there with a furnace filter or two - but - attics have kinda a dis-stink-tive odor from dealing with all the heat, yet - my roof is a darker color and it does get toasty up there but not to the extent that a special designed place would and nowhere near as quickly...

still - that's the type of thinking I like so thank you...

If you have a "dis-stink-tive odor" in the attic you have a bigger problem to deal with---MOLD!!!

J Tiers
11-30-2012, 09:24 PM
If you have a "dis-stink-tive odor" in the attic you have a bigger problem to deal with---MOLD!!!

Attic smell is quite different to mold smell.

And mold generally needs moisture..... my attic hits 130 degF, not much chance of moisture and mold up there.. and I suppose T A B would have a similar hot attic that is extremely unlikely to harbor mold (Seattle residents may ignore this comment)

The Artful Bodger
11-30-2012, 09:41 PM
I was wondering about mold if moist air from the swamp (evaporative?) cooler is being pumped up there.. no chance of mold in the roofspace here.

darryl
12-01-2012, 12:10 AM
If enhancing your heating and cooling system as you described will save you money, that's great. If it can be done with 170 watts or less ( and it will have to work on much less power a lot of the time), then installing and running it from 110 would also save you money. Could you save $3 per month by using the solar panel to run the system instead of AC power- I doubt it. It will be the fan system you use that would create the savings, not the use of a solar panel instead of 110.

If your use of the panel was to lessen your use of a gas generator to supply power, then you might save significant $. At the same time though, your usage habits would have changed to allow you to get by with just the generator, even if enhanced by the solar panel. The typical situation where you would be willing to do this would be out in the boonies in a cabin, or some similar situation. That's where the solar panel would really have its place.

I'm not knocking your use of the panel this way, but if it's to save a dollar then I don't think you'll see it. Personally, I would find it novel just to have it in use somehow.

A.K. Boomer
12-01-2012, 01:00 AM
You are going to cook the fan from low voltage on cloudy days as well as sun rise and sunset.
I speak from experience.
Google up a linear current booster. Install it between fan and panel and you are good to go.

You make allot of sense, I will check it out and thanks for the comment.


Darryl your right about where the real savings is occurring, by either introducing heat or coolness to the house, I just thought it handy in both circumstances that the panel will be getting power at the same time I need heat in the home (winter months)- and also the panel will be getting power the same time I need to cool the house - so it's just a supplemental thing, for me it's just trying to find a good use for one single panel... Evans Idea is a good one too but im thinking why not just get the LED's for the house and save on my electric bill and have them all 110 and with all the switches already there and sockets and panel wiring, or are the DC's way more efficient or something? plus really don't want the expense and have to mess with any battery's...


Lot's of good idea's - keep em coming... :)

A.K. Boomer
12-01-2012, 01:23 AM
You are going to cook the fan from low voltage on cloudy days as well as sun rise and sunset.
I speak from experience.
Google up a linear current booster. Install it between fan and panel and you are good to go.

Ok - just quick checked the price of a LCB and it would make the system impractical from the get go,

isn't there some kind of cheap voltage cut in electronic part I could just wire in - heck even some diodes do that don't they - keep in mind this is going to be a very free turning fan so even the most miniscule current will get it rotating and even if it's slow it will be free from resistance (on the blades),,, and if it's not even enough to get it to rotate then Im thinking it would not even bother it for heat build up no?

Ok - tell me what you cooked :eek: was it a fan or was it a water pump that had to overcome seal drag???

darryl
12-01-2012, 03:29 AM
It does take a fair amount of power to move lots of air. This is a continuous loading for a motor, which means the current draw will relatively high while the fan turns. As the voltage drops and the fan slows, the current draw will lessen because less air is being moved. If the motor is reasonably efficient, it will continue to run down to perhaps 4 or 5 volts or so. At stall the motor will be drawing little more than the idle current, and that at the lower voltage. It's quite possible that the motor can survive this easily. I don't think I'd have a problem setting up a test and letting it run.

Now there may be a problem when the attic is baking hot and the motor is running very slowly or not at all, but these are conditions when the sun it out so there should be no reason for the motor to be running slowly.

You do have a couple options- one is a temperature cutout on the motor, and the other is to add a battery to the system. The solar cell would have to not only run the motor, but keep the battery up as well. But if the battery is fully charged, it won't be drawing current, and it can help keep the motor rpm up for awhile when the solar panel output dips- say for clouds going by, etc. For this all to work in harmony, you would need some kind of controller- this may be a deal breaker because of overall cost.

Having the system operating could save you money, so regardless of how you power it, it would be worth installing. Should you choose to power it via the solar cell and back-up battery, you are also getting a back-up battery- this you can work into an expanded system that includes led lighting. An ac adapter can be part of the system, and for the little power that would draw the added cost for hydro would probably not be noticeable. The lighting would mainly be used for power-out situations and temporary lower level light.

Working up this system would cost money, so - let's try to think of a better use for the solar panel-

A.K. Boomer
12-01-2012, 09:22 AM
Some of the savings are in the form that's hard to calculate,
I have a massive sun porch on the south side, even though it's only single pane glass it gets nice and toasty on a fairly cold day so I just open up the front house door and the south side of the house benefits,

other than that I keep the house fairly cool (64 f) yet the bathroom is on the north end and is always chilly - on the average that's ok till you go to take a shower,
I have a wood burner but don't always feel like building a fire just to take a shower so I kick on the gas heat to get that end of the house up to temps,
point being is even if this little system just kept the bathroom warm the majority of the time then it would not only add to overall house comfort but stop me from having to make thermostat adjustments like that and save not only gas but electricity from not having to run the furnace fan....

Point being - I don't think it would put a massive dent on what the centrally located thermostat is experiencing as much as it would help "curb" the human element of manipulating said thermostat due to one small room that is important to keep warm once in awhile...

J Tiers
12-01-2012, 10:38 AM
It does take a fair amount of power to move lots of air. This is a continuous loading for a motor, which means the current draw will relatively high while the fan turns. As the voltage drops and the fan slows, the current draw will lessen because less air is being moved. If the motor is reasonably efficient, it will continue to run down to perhaps 4 or 5 volts or so. At stall the motor will be drawing little more than the idle current, and that at the lower voltage. It's quite possible that the motor can survive this easily. I don't think I'd have a problem setting up a test and letting it run.

Now there may be a problem when the attic is baking hot and the motor is running very slowly or not at all, but these are conditions when the sun it out so there should be no reason for the motor to be running slowly.



Fans are generally a "cube law" load, so they slow up rapidlyas the power input drops, and match to the load. I would not think there is ANY problem unless the fan is too large for the motor, or the motor is physically blocked from turning by friction or obstructions.

I agree there are likely better uses. A battery and inverter for power backup is one obvious use. The fan can STILL be used as a "dump load", so that when the battery is full, the regulator diverts the panel output to the fan. I use that system out in the shed.