First try at making my own electricity!

[iamdewayne]

Hi guys!

I'm ready to buy 5 190 watt solar panels and would like views and opinions from the board.

I live in Dallas, and have room to put them in the back yard ( they are 3' X 5' each ) and still get a full days sun on them.

I am building the redrock single axis tracker to increase the available sun time.

Already decided to use a Mppt controler since the panels are the same size.( I read that you can't mix outputs with a Mppt controler cause it adjusts the voltage to get the rated amps and they all have to be the same for it to work properly.

This will not be grid tied, I have 4 forklift batteries ( 6 volt ) that i will run one circuit in the house with, which just happens to connect all the lighting and the entertainment center using a  24 volt 2000 watt true sine wave inverter.

A few questions.

1. Why is it important to have the UL rating for solar panels?

I see a place in fla that sells non-UL listed panels, new ( 190 watts by evergreen ) for $2.85 per watt.

The same panel, new ( cosmetic bldmishes, but fully UL listed and 25 year warranty) is $3.40 per watt.

The same panel new, no blemishes 'factory "A" grade ( but same warranty and power test as the blemished panel) is $4.25 per watt.

2. Am I using enough panels to keep the batteries from discharging too low?

I already changed every light in the house (30) to a cfl type bulb and am working on some led lights ( soft white ) to further cut the power requirements.

The TV is a flat panel 42". I don't know the power requirement for it, but I do know it's more effecient than a tube type.

Thats all I will use the panels for, unless I can get this pc on the circuit and still have power to the TV which keeps the wife happy.

Anyone care to take an (semi) educated guess on my questions?

Thanks in advance.

[disaray1]

 Dewayne,

  The UL rating isn't required for non grid tie systems, so as long as you never try to grid-tie those panels, you'll be ok. (there may be other negative aspects about the non-UL that may be of concern but I listed the one that came to mind first) As for the rest, you have to do some leg work first.

 What's the amphour rating on those batts?

 Are they SLA or other?

 Do you own a "Kill-a-watt" meter? If not, get one ($25) and find out what your total consumption is- then we can better answer your questions.

 Your headed in the right direction. Keep us posted.

 David

[iamdewayne]

Hi David, thanks for the reply.

The batteries came from a rental company here. They were pulled from a 'boom' lift

cause they wouldn't last more than 3 hours before needing to be recharged. I got them for the core value. ( core charge ) I dont know the rating on them, but they are about 2' tall by 10" deep by 15" wide. ( those are eyeball guestimates )

I have an old charger from my r/c airplane flying days that has always seemed to make batteries stronger as in bring them back to life that I ran on each one for a week and they do seem to be able to hold a better charge now. ( guess it's time to get a hydrometer and start really testing ) They are lead/acid batteries, about 300 pounds each.

I will get a 'kill a watt' meter and see what it says.

This all came about when GPL, ( my electric utility ) went to 13.5 cents per kwh

and told me I was using 44 kwh per day in my house this spring ( we had a nice long spring that didnt require a/c )

Since I might someday grid tie them, I will stick to the UL listed panels.

The evergreen site says they are 'poly-crystaline' ( not sure what that is, but hey...it sure sounds cool  )

[ghurd]

Think about this.  Why would someone sell "The Same Panel" for almost 20% less?

If it is actually the `same' panel, then why isn't it UL Listed?  It should be.  Maybe there is a problem they know about?

I wouldn't trust them.

That will be a lot of solar power in a pretty good area.  If it can keep up will be determined by how long the TV and lights are on.

Plasma TV's take more power than CRT.  LCD is lower power, won't `burn', and last longer (I believe).

Low cost per watt is often hiding something else.

Remember to figure on some crazy high shipping costs. Sending a pallet isn't cheap, even if it's almost empty.  Fuel surcharges, this charge, that charge... Possibly a crating charge too.  Certainly insure it.

"What can Brown do for you?"  They can charge over $400 to bring a 1200 pound skid 60 miles!  It's usually not nearly that bad.

G-

[Nando]

What is your name?

I am in Richardson, let's connect via email, correct the anti-spam in my email address.

I can assist you .

Nando

[sh123469]

One other thing about the non-UL panels is that your insurance company might refuse coverage on an electrical related problem (fire, etc.) if the panels aren't UL rated.

Although you can't be legally required to use UL listed, you can be contractually obligated.  Check your policies closely or call for confirmation.

[disaray1]

Ghurd,

 The panels he's looking at from a place in Miami also caught my attention and I called them on it- the brief explanation was that these panels were manufactured for export from the US, and that the UL certification had not been applied for, for cost purposes only. I think its rather expensive to go through the UL Cert process, and if the product is not intended for the US market......you get it.

 David

[ghurd]

I've seen that explanation and I personally don't believe it.

My understanding is the `product' gets the UL Listing.  That is the expensive part.

If it is the same panel, it would be covered under the same UL Listing.

Why not just put the sticker on it?  Stickers can't be that expensive.

So it's back to why sell them so much cheaper because they don't have the sticker.

Some of the `for export only' PVs I have seen have no warranty.

Some PVs made for export (but not Only for export) have a different J-box. The foreign type box is not UL Listed, but the cost was the same as the UL PVs with the UL box.

The UL listed box can't cost $266 more than the European box.

PVs are in short supply, so why would Evergreen put a box that costs the same, on the same PV that already has the UL listing, and sell it for $266 less?

Something fishy going on there.

G-

[la7qz]

Hi

Why not change your lights to 24V DC and run only those things that need AC off the inverter? It'll be much more efficient. I've been living totally off grid with solar power for years. (On two different sailboats.) Everything that can possibly be converted to run direct from my ship's batteries gets converted as it arrived onboard. The inverter is rarely on and is only used to run stuff that can't be made to run off DC. (12V in my case).

I'm typing this on a laptop running off a 12 - 18V converter. Much less power hungry than running it off the DC - AC inverter and then using the original power brick to convert back to DC. When I really need to conserve power, I pull the battery out of the laptop so I'm not wasting power for maintenance charging a full battery.

Other than that, I'd say you're heading in the right direction. Since I've never been to the US, I don't know what the UL listing means. If the panels look the same, I'd simply wire them up and test them side by side. If they won't let you take them home to test, you could probably try it with your car battery. Leave some loads on like full beam headlight, heater fan etc with the engine stopped. If the panels produce the same and look the same, I'd go for the cheapest and get more of them. To make a fair test, you'll need two (preferably identical) multimeters measuring amps going into your battery, and make sure both panels are getting the same amount of sun. I suppose you could do it with one ammeter if you bring a blanket to cover one panel then the other.

Regards

Owen

Yacht Magic

Anchored French St. Maarten

[iamdewayne]

Thank you all for the comments.

Ghurd, I have been thinking the same thing, thats why I asked here. I have lurked here for a few months now and have read and re-read most of the posts here in the solar section.

I thought that maybe posting now would get some responses to help me in the final choosing of the panels. ( I was right )

I will stick with UL listed 25 year warranty panels.

Nando, I'm over in Garland, moving next month to a house thats exactly 1 minute from 190 and levon. I'll email you and perhaps we can talk.

I'm pushing 50 as hard as I can, and am tired of 'talking about making a change...', so I'm just gonna go ahead and do it.

I have an associates degree in electronics that I've never used other than for tinkering, now I'm starting to realign my priorities and am making it work for me.

At 3' by 5' these panels appear to be small enough that they wont be visable from the street which is a good thing.

I don't understand enough about net metering yet to even think about grid tying them, but I hope that is in my future.

I guess I better google up the term poly crystaline.....

Thanks again everyone!!!!

Dewayne

[iamdewayne]

Hmmm.... I see where they just lowered the price on those non UL listed panels to 2.74 per watt....

That is starting to make me wonder whats wrong with them even more....

[kenl]

 Glad to see your making the leap. I'm using some of those non UL listed panels and see no problem with their proformance or safety. Here's how I'm set up right now. 6 110w Suns and 2 120w Kero's running through a combo wind/solar charge controller. This feeds 16 12v 40ah batteries wired for 24v. I run ALL our lighting (39 14w CFL's) my TV, 2 laptops, a desktop when I need the extra computing power and a lot of phantom loads due to chargers etc. In the winter add the pellet stove to that. I plan on putting the fridge on solar during the day when there is excess watts beyond what the batts need. Ghurd is helping me with the design on a controller system for that.

 Now for your questions. UL tests products to make sure that they are safe for their intended use. As David said if your not going to grid tie it isn't an issue due to no inspection. You need to decide for yourself if you feel comfortable buying none UL products. The second question is harder to answer, shooting from the hip on that one I would guess you have too much solar for your batteries. You may want to concider grid tie, there are days I wish I had just for the fact that most days I produce more watts then I can use with my current set up and still have 4 more panels not connected to the system yet. You can still have a battery back-up system with grid tie and You'll be able to use all the wattage of your new system. kenny

 

[spinningmagnets]

Dear Owen, "UL" means "Underwriters Laboratories" thay are an electrical device certification service. A device that does not have the UL insignia may have aluminum wire instead of the more expensive copper, it may have wire that is too small for the rated current, or it may have insulation that is too thin or of a poor performing type that is less expensive (or any one of a dozen other cost saving "short-cuts"). I'm not saying that a particular gadget doesnt work, or isn'r safe, but the "UL" cert is a minimum reasonable standard. -Ron

[iamdewayne]

Wow, been a busy week!!!

As I keep reading, I get the idea that I need to run the panels in 'twos' to get it to work with the MX60 @ 24 volts out. Instead of 5 panels, I may use 4 and series them for the 24 volts. (Already own two 24 volt true sinewave inverters)

My batteries are up in Duncan at the farm, but I believe they are about 800ah rated.

( they are HUGE )

Still need to get with nando about ideas on how to make it work.

I may get a non-ul panel for the farm, but for here in dallas I'll stick with the UL listed 'blem panels.  I still havent seen any for the $3.40 per watt like these.

Eventually, I will get around to small wind power, vertical, for in town.Darius maybe... could paint it up like a Texas flag...

I dont think two wmall verticals on the roof would cause the neighbors to go nuts...

If I could get them to put out around 50 watts each I would be set, but thats down the road...(already have the magnets and wire bought for them, working on a do-able design)

Seems like everyone wants big wind power, but in the city it isnt gonna work.

Gotta think small...

Dweayne

[howlet]

I recently acquired a copy of the UL Standards For Certification of PV Modules. As was already stated the certification process is very expensive. The copy of standards book consisting of the tests and proceedures for certification sells for $800 alone to the average consumer. Thats just to find out what a panel must be capable of withstanding.

The testing is so rigorous that the 5 or 6 panels that must be submitted for testing will be completely destroyed. Not to mention the cost of the testing itself.

 Initially I had planned on getting certification for the panels that I'm fabricating. After realizing that the UL certification was out of my reach for the moment I decided to use the standards book as a reference for building a safe and quality panel for off grid applications.

I cant imagine the dreadful feeling of forking out all that money and not passing the certification process! Jeff