Harbor freight solar panels

Here's what I'm finding on ebay.
It's a similar, never heard of before company which probably means that they're coming from China and having a brand name slapped on them. They even look similar to the ones you found on Amazon.
Good reviews too.

RAMSOND 120 WATT W 120W PV SOLAR PANEL MODULE 12V RATED - eBay (item 360253874524 end time Jun-16-10 09:42:36 PDT)

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We've discuss a couple different types of solar cells in this thread, the Amorphous or A-Si panels which are found in the cheap Harbor Freight panels and also in the good quality commercial Uni-Solar and Kaneka brand solar panels have a few strengths one being that they handle high temperature conditions better than crystalline cells, meaning that as the temperature of the solar panel heats up the panels will produce more power when hot compared to crystalline panels at those same temps.

Amorphous panels also produce power in lower light and overcast conditions.

Amorphous cells are not size efficient meaning it takes more surface area to generate the same amount of power than crystalline panels, or in other words an amorphous panel will be larger size wise than the equivalent wattage crystalline panel.

Amorphous cells do not use rigid crystalline structures so they bend and flex and won't crack or shatter. However don't confuse the solar cell with the glass glazing that covers the solar cells. The glass can still shatter on any panel though some panels like Uni-Solar do not use any glass in their construction. One thing to look out for in many of the cheaper panels such as HF and others in that category use a thin almost window glass that will crack under constant use due to the contraction and expansion from the heat and cold. The commercial panels generally use a good quality tempered glass that will withstand the weather and take abuse much better.

The mono and poly crystalline panels come in many grades and quality. A grade is typically more efficient but B grade panels are fine though not as efficient in producing power so their wattage rating will be less for a similar sized panel compared to a grade A panel.

There are crystalline panels being made from even less efficient and substandard solar cells that are being sold on eBay and other places at "terrific" bargains. The panels work but their working characteristics won't match the higher grade panels so they may produce rated power in a much narrower spectrum of light and temperature, meaning that a higher graded panel will produce more power in the same number of sun hours in a given day than the "bargain" panel can even if they have the same wattage assigned to them. You get what you pay for in other words.

I started this post with the desire to simply share a good buy I found on a commercial 55 watt solar panel. It's a Kaneka brand 12v nominal amorphous type solar panel and is available here on sale: http://www.solarblvd.com for $95 + shipping from Calif. Here's some info on the panel from the manufacturers website: Why Amorphous? : Kaneka silicon PV

 

Late to the party as usual,but I have been looking at these people and they have from what I can see a fairly good product and sometimes a very good deal!!
Welcome to Solar-Deals.com! - Solar cells, solar panels, and solar panel systems

There is a article on them here .

Solar-Deals.com Slashes Cost of Solar Panels by 50%

I don't know as much you guys seem to about the subject but I just got 108 cells for $89.95 in a deal they were running and they are the monocrystalline cells .I plane to make my own and see what happens. JMHO

 

The "glass" solar panels as you call them will outlast the amophorus solar panels by about 10 to 1. I have been living off the grid for about 15 years and I know this to be true. Some of my Glass Solar panels are still going strong. When you need to depend on solar to run your entire house as I do, you want good ones, not the el cheapo Chinese ones. They will only give you good power if at all for a year or to. Besides all of this you are going by the rating as touted by the seller, which is ususally not true. What the panel says on the back is generally "max power output" which means unless you are one of the luckiest people around, you will not normally get very close to that. What you WILL get is about 85% of the max rated power. The cheapest place to buy the golf cart 6volt batteries is at the golf course's. My friend had to replace his after 12 years, and they were selling for about $125 at the local solar stores and he went down to phoenix , called around and bought them brand new at a golf course for $75 Check around as they can be had much cheaper.

 

Buying solar anything from Harbor Freight or Northern Tool or anywhere else like it is like sending in your match fire arm to have them accurize it for you or repair it. Would you consider such a move ? I don't think so, buyer beware of the products being sold as "solar Generators" that is out there. They can also burn your house down under the right or wrong conditions. These are the worst of the worst so to speak. Do not go there and throw away your money.

 

Here is how solar panels are rated. All solar panels are rated in Watts. The watt rating is how much power (amps times volts) the panel will produce in full sunlight at 25 degrees C (77F). This is the industry standard (STC) for all PV panel ratings. However, that is a "best case" scenario, in actual real life on a year around average you can expect 10-15% less for all panels. And that my friends is for top of the line panels. From the chinese junk panels littering ebay, harbor freight , northern tool etc, you should expect much less performance then even the best of the best

 

Here's a great link I came up with while doing the research. The diagram of a typical setup is worth saving all by itself!

Solar-powered refrigerators by Jeffrey Yago, P.E., CEM Issue #102

 

They are not cheap but many modern wind turbines can tilt back under heavy winds, reducing turbine speed and are rated to at least 90 MPH winds. That's important here in Western WA State because we do get the occasional freak windstorm that goes over 90 MPH

Here's one such manufacturer. We are definitely going to have at least one turbine on one of our tower tops

Buy Wind Turbines for Homes, Residential and Commercial Use.

 

Maxflax. It is simply a different design. I have a neighbor (2 miles away) with the tilt back design and he has had to take it down twice and send it back to flagstaff for repairs. I have the brake type, and so far so good. Mine is designed to take wind speeds of up to 134 mph. with no problems.

 

Thanks for resurrecting this thread. I've been wondering how the solar panels stand up to hail? We generally get several hail storms here each year, and about every 4th or 5th year, we get hail so bad we have to replace our shingles. So how durable are these things????

Thanks!

Kajun

 

Hi TXKajun. I live just west of you up in the n.e. az. area. We too get a hail storm now and then, and for the last 16 years, I have worried, but have not had a single problem with any of them. But always remember this, anything made by man can be destroyed by nature in a flash. I simply keep a large homeowners ins. policy on everything just in case.

 

Thanks, do you have links?

 

i'm new and this is my first post here. here is what i have figured out about solar and wind power in kentucky.

i have 8 sets of the harbor frieght solar panels. i have gotten great performance out of them. i am getting just 5 watts under what they are rated using a mppt charge controler. my battery bank is divided up into two banks. i am using 2 volt batteries designed just for solar and wind power. to say they are not cheap is a understatement.

i have 6 windturbines hooked up to the battery bank as well. i have made special mounts for them. the blades are on a rod i pressed sealed bearings onto and pressed a stop on for the blades. i threaded the end of the rod so i can use a nut and locking washer to hold the blades on. i mounted a 14 inch pulley right behind the blade stop. on the pma's i used a 2 inch pulley. i am getting 14.5 volts at 2.5 amps in a 2 mph wind now. my pma's are three phase a.c. that i retify back to d.c. current. in high winds(10 mph and up) i have seen out put of over 330 volts at 7.9 amps on each turbine.


i have a 3600 watt solar bank grid tied to my home. i used 100 watt panels when i built this system.


now lets focus on the problems of solar power. in the summer the heat lowers your output. the hotter the surface gets the less production of power you will see. then comes the angle of the panels. in the summer time you lower the angle. in the winter time you have to raise them to a higher angle. when they sun is behind the clouds you get ALOT LESS POWER. roughly just about 10%.

i have mine setup on a ground mount made of treated wood. that way i can clean them regularly and incase i have to bug out i can take the panels out, take the mount apart with a cordless drill and go in under a hour.

you need to use wind and solar becuase there will be days when the sun doesn't shine but the wind blows and days the sun shines and the wind doesn't blow.

then there is the battery bank. you would idealy have 2-4 times the storage than what you would use in a few days. i do that becuase you never know. deep cycle 12 volt batteries will work, but are not the best. 6 volt golf cart batteries are a better choice for solar and wind, but not the best. the 2 volt batteries have a much higher amp hour storage rating. by the time you have six 2 volt batteries you have 3-4 times the storage of say a 6 volt battery bank of 6 batteries. by having two 12 volt banks made of 2 volt batteries your way ahead.

now a 12 volt system isn't as good as a 24 or 48 volt system. the reason why is the guage of wire used and the inverters used. the higher the voltage the smaller the guage of wire you can use for longer runs of wire. on my 12 volt system i am using 1/0 wire for a 25ft run. i know it is over kill, but i'm not dropping my amps that way at all.

charge controlers is something that needs to be talked about. a mppt(multi power point tracking) controler will allow you to up the voltage coming from the panel bank and it also makes your panels produce maximum power output. i'm using a 80 amp out back on one of my banks going to my battery bank. it is a bank of 12 100 watt solar panels. i have them set up for 24 volts going to the outback. they are really putting out just over 22 volts each so my input into the outback is around 45 volts. the outback drops it back down to 14.5 volts for charging the battery bank.

i have another mppt charge controler on the 8 sets of harbor frieght panels. i have them hooked up the same way as 24 volt(45 volts actual output) 14.5 output.

the wind turbines are hooked to two scorpion charge controlers from missouri wind and solar. they are amazing charge controlers. i have micro grid tie inverters hooked to the dumpload sides of them. our power company doesn't come back when you get the approval for a ul listed grid tie inverter so the micro grid tie inverters go under thier radar.


i'm doing all this for our next home. i plan on being totally off the grid in our next place.

 

How about a few pictures of your system ?

 

if i get time and get used to being on here. i normally don't post pictures for reasons we can all understand.

i figure since i pay no electric bill anymore i have about enough to cover our needs in our next home. i might be able to get some pictures of my home made turbine mounts when i put up another turbine, that will be next month. that is the best thing i can do for you right now. that way nobody can run programs and figure out where the inside of my garage is. i might even be able to slip a few pictures of the battery bank in there. i'll have to really think about it.

 

here. i will go this far for you. the charge controler i use on the harbor frieght panels.

one of the mount with 4 sets of harbor frieght panels.

first rack of 100 watt panels.

i'll try and get some more pictures up when i get home on my other computer. i have broken one of my own solid no picture posting rules!!!!

 

i'll post them when i make the next bracket. that was my brain child. i had been mounting the blades straight to the pma's and we don't get enough wind to really do any good that way, but by using a 14 inch pulley on the blades and a 2 inch pulley on the pma's i started making power in lower winds. i'm thinking of trying a larger pulley, but the pma's drop off after a certon point. i might try a larger pulley on the next one and see what happens. we really don't get that many winds over 10mph yearly here.

another thing i did was i mounted the pma striaght under the blades. i was afraid if i mounted it on one side or the other it would make it unballanced. see if this works.

this is with the blades on the pma. these blades are 52 inches in diameter. i have a set that each blade is 4ft long and they have alot of torque!!!

 

i have also switched over to these.http://www.prestowind.com/page/1maq3/Our_Products.html
well i was trying to show the m-24 2 stage model. look them up.

i can say they truely work just like jim says. he has been making wind turbines for over 30 years and he knows his stuff. i have 6 of them up and working right now. if a windturbine is in your future i can say for sure these truely do work just like they say they do. they work even better set up like i did mine.

here is the charge controler i use on the turbines. i have two of these in use at the moment and for the turbines they are the best i have used so far. http://www.mwands.com/index.php?main_page=product_info&cPath=4&products_id=489

 

Solar system design is task oriented.
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System is designed for 2.4X the required load (minimal figures based on Max loads).
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Battery systems are designed to be discharged at a rate not to exceed 20% of Rated 8-Hour Discharge Rate. They are re-charged at 10% of Rated Amp Hours (ampacity).
Since you "need" a reserve capacity, and limiting the amount you discharge the battery's in discharge cycles has a direct effect upon battery life (ie: the more you discharge a Battery bank lower than 50% of Rated charge- and the faster you discharge it, the less recharge cycles that the battery will survive through) you want to keep your recurring battery discharge rate to 40%.
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That said, your battery bank needs to be designed/configured to give you twice as much battery power as you need.
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Now the inverters must also be over rated to extend their life cycle. If you are using inductive loads you must also add back EMF diodes to the motors to shunt any inductive loads that are a result of collapsing motor winding fields. So the inverters need to be rated at least 1.5 times the Instantaneous loads for motor start up (ie: at least 2.5 times the average totaled motor loads).
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Railroad signals get around this because they are DC devices, there are very few inverters, except in crossing gates which are geared AC motor driven).
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Hail is a possible concern, but is mitigated by panel angles. However, if the hail is coming from the south and falls at an angle that intersects the panels plate by anything less than + or - 15 degrees from straight on - YOUR PANEL WILL SHATTER. Hail strikes at shallow angles are not generally a real concern. Besides, you can malke a panel hail resistant by mounting a 1/2" thick UV stabilized lexan sheet over the glass plate. The lexan can be replaced/polished every 5-10 years (or as needed). This is the system that I use in my Tennessee Property, in Arizona I haven't had any issues, but I do have 1/2" lexan on my Arizona Panels as well (hail storms in Phoenix, are rare, and the one we did have broke a lot of windows. My favorite one was a lady who pulled into a parking lot and parked her car so that the windshield was pointing away from the hail. Needless to say, her back windows were broken, and the cars parked on either side of her had unbroken windshields pointing towards the hail stones... dah...)
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Solar panel costs per watts were coming down significantly, up until three to five years ago. The Chinese Solar Company's are getting smarter, and greedier as well. The Chinese solar company's unwillingness to accept less than 1,000% profit margin (since they have the least environmental restrictions, and cheap slave labor rates they have the highest manufacturing profits in the universe) is what kept solar power pricing above $1.00 per watt. Had China continued on their quest to undercut all other competitors solar power would now be less than $0.25 per watt.
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Incidentally, in a solar installation DC-Watts and AC Watts are essentially the same. A 100 Watt AC load is the same as a 100-Watt DC Load. The issues are how the watts are figured.
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As for panels, no actual uniform rating is applied. A 210-Watt manufacturer rated Solar Panel may very well be less power than a 180-watt panel. Why? Its a play of words.
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Most small consumer solar installs use 13.8V (12VDC) Battery systems. So the Watts should be calculated using 13.8VDC as reference. But the panels are capable of putting out a maximum of 19VDC at 11 Amps - so 11 amps times 13.8 is 151.8 Watts (not 210-watts). But the 180-Watt panel is rated at 180-Watts at 16 VDC so the math is 11.25 Amps. Apply the formula of 13.8VDC times 11.25 Amps and you get 155.25 Watts...
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Now consider that you panels will only perform at about 70% efficiency (unless you live at the equator and are pointing your panels at the sun with a precise solar tracker) you can easily determine what your predictable power capacity really is... BUT....
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This is a really big BUTT....
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Your wiring is also a determining factor. You cannot just use any wire to hook up your arrays. Yea, I know the panels come with those cute little 12 Ga pigtails, but that is the gauge required for the rated amps at only the distance of the pigtail. When you add more wire you must increase wire size. Normally, you run the pigtails into a junction box (the solar ndustry calls these combiners... Dah - Junction Boxes). From the junction box to the battery bank wire size is determined by ampacity ratings, not just wire gauge. Adi Pheiffer wrote a Book about Solar Power. I suggest you look it up at the loacl library and check it out, read it two or three times and copy the amacity conversion tables. Adi is the ultimate Solar Geru...
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Here is a link to the book on Amazon ...
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Amazon.com: The Easy Guide to Solar Electric Part II, Installation Manual (9780967189123): Pieper Adi: Books
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If you want to truly understand Solar Power Installs - This is the book...
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Dave
Phoenix, AZ