ECN Forum Forums General Topics of the Trade Alternative Energy PV panels

Someone said to me the other day about the new PV panels. They said that the life expectancy is about 10 years. I thought it was longer than that, but I didn't have any facts on me at the time. Does anyone know what the life time of a PV panel is?

Also they said that once the panel is no good, they would have trouble trying to get rid of the old panel. They said that you just can't throw them away, they have a lot of bad things ( Bad for the environment that is) on/in them. You need to have a special place take them away. Does anyone know if that is fact or fiction?

The performance does tend to fall off as they age. How much is still a variable, based on lots of factors but 50% in 10 years may not be totally out of the question. It is hard to find hard data on this.

As for getting rid of bad ones, it all depends on your local land fill rules. It is not any worse than an old TV or PC board. I assume once these become prevalent, there will be a program for safe disposal but that is part of the long term cost.

Harold:
FWIW, the panels on the job in the "Big" thread are supposed to be 25 years, according to the PE at the site.

As to 'disposal issues'...I have no clue.

Talking to the PE, his company requires and pays for an additional 'test' from the mfg. before the panels are shipped. He indicated that this 'test' is extra $$$ on the cost of the panels. Fail rate at the 'Big' job is expected to be at or near zero....but I hope that is not wishful thinking.

It will be a while before they begin any testing at the site, as far as performace.

Just a quick FYI from one of todays plan review projects.

BP Solar info:
BP 3215-B, 215 WATT Panel
Warranty info:
Defects.....5 years
90% output..12 years
80% output..25 years

Most should be available at the mfg websites

That certainly sounds optimistic ... but they sell "30 year" shingles in Florida too
Sometimes I think these warranties are written, based on the CEO's estimated retirement date.
"Sue the next guy"

What is the recourse on this limited warranty? (they are all "limited")
Do you get a new one free?, Is it a prorated price on a new collector? Does it cover labor? Permits?

If it is like a shingle warranty it is pretty much useless.

Greg:

Try the following link to BP Solar for warranty....

http://www.bp.com/sectiongenericarticle.do?categoryId=9019650&contentId=7036652

Interesting reading
No labor coverage and they can choose to just give you another used collector or two to run in addition to yours to get up the the percentage of rated output for the total array.
You also need to show proof nobody but a certified BP person has ever worked on this system.

Needless to say we have a pretty low opinion of BP down here

Greg:
Understand that I did not 'pick' BP Solar, that was one of my plan review jobs this AM, and the warranty info caught my eye.

I was just curious because I have not seen estimates of efficiency going that high.

Greg:
I'll skim other info from different mfg as it goes over my desk.

Did you look at the mfg of the panels in the 'small' thread (Petrasolar.com)

I did look at that site but I was looking at the size and price. I think the 120v micro inverter may be the best system for homeowners dabbling in the technology, simply because it is plug and go. You can add on as your wallet permits.

I wonder how GFCIs deal with power coming "in"? In real life I assume they don't know the difference as long as the hot and neutral are balanced.

I am guessing that if you wanted to start hanging micros on your roof, all the EC would do is sell you a bunch of receptacles across the roof with in use covers.
The immediate concern would be derating the wire in the raceways. Other than that is would be the same as the any other receptacle outside as far as I see. (GFCI circuit, in use cover and a "wet location" device in a Bell box)

I was also thinking about how you could kick start these if the utility was down. I wonder if you had a regular 12v > 120 inverter (maybe also solar powered) you could switch on line after you isolated the PV system from the utility and the bulk of the house load if it woulds kick in and generate full power.

John & Greg,

I was just wondering if you guys heard about removal of these PV systems? I didn't know if this gentleman knew something about the hazards or just blowing smoke.

Harold:
You lost me there!

I'm looking for 'dosposal' info of panels and haven't had much success yet. Usual reply was something to the effect of '25 year life expectancy'

I doubt it is a serious problem but virtually all electronics are called hazardous waste if you have any quantity. It is probably more because they are not sure what is in there than what is actually in there.
You will have trace amounts of various heavy metals. Just enough to get eco folks' panties in a wad.
The scrappers would reduce the overall load by taking every scrap of aluminum and steel out of the framework if you just set them in front of the house.

I was talking to another chemical engineer the other day and I asked him the same question. He wasn't sure what "hazards" might be inside of a PV system, he did think that Germanium might be in there. He also said that germanium was a heavy metal and that would have to be disposed of properly. I will ask the next PV installer that I see and ask him what they do with an old panel. ( If they even have "old" ones by now.)

PV Panel life is usually warrantied for 25 years with approx an annual degradation of 1% each year.

Los Angeles Electrician Los Angeles Electrcian

Branover:

Welcome to ECN Forums, from one of the 'Jersey guys'

Nice to see new members jump right in.

That would be an interesting experiment to see what the PV puts out under a street light. I doubt it really returns that much. The light is not that efficient in the first place and we hope most of the light is actually hitting the street. Then you divide that by the efficiency of the collector and subtract the losses in the inverter. A watt or two out of the 150w would surprise me. I also wonder if they get some energy from IR that will be there on a hot night, even if it is dark.

Branover,

Welcome to the board from another Jersey guy.

John, Greg,

I was talking to a PV installer yesterday and he told me, if they break anything on the PV system, they will ship the broken item to India or Pakistan. They will break it down and recycle the pieces/parts there.

I have only dealt with a few panels brands but the one I have come with a 20 year output warranty of at least 80%. In general manufacturer under rate their panels since they degrade over time form the elements and backing in the sun day in, day out. a 130 watt panel out of the box will put out 135 watts or more at 80% is like 103 watts in twenty years. More then likely, they will be added to or replaced of just forgotten about by then.

Solar efficiencies have now reached performance levels beyond imaginations forty years ago.

20% and beyond is now becoming common. The nicer aspect is that a smaller foot print makes installation even more practical.

There is still a range in performance per panel: 175 to 215 W/Panel... with the panels being similar in size.

Never mentioned but relevant: the array shades the roof. For us in the southern climes, that's not a trivial thing. Air conditioning loads are the peak driver of juice demand -- and shading the roof helps a lot.

The bigger concern for any installation is maintaining the integrity of the roof. In the rush to install I can imagine a lot of flakey operators taking short cuts on the roof seal.

I'd have long ago installed solar. But I can't find any mounting able to overcome Spanish tile -- the classic stuff. It's brittle and drills poorly.

Yes, the roof could be an issue. I'm not aware of any resi or comm leak issues, and tile roofs are few and far between over here.

Spoke to a PM today as to an upcoming comm job (4.26MW) scheduling. The roof rip-off should start tommorrow, & be about 3-4 weeks depending on weather.

BTW, one ground mount job has 225 watt panels.

The 'shading' thought never crossed my mind! I'll have to get one of the PM's to get some temp readings, perhaps an additional 'sales tool'??

I just thought of another question. If you want to re-roof your house, would all of the PV panels have to come off in order to re-roof the house?

Yes the solar panels do need to come off if you re-roof. That is actually the best way to get some used ones cheap, particularly if the roofer blames the leak on the collectors. That is where I got my pool collectors (8 for $150)

Greg,

You are always thinking! Keep it up my friend! On a more serious note, that would mean that the price of a new roof might double? I don't know how much a new roof goes for. ( Thank God) My roof is brutal with 12 on 12 pitch pretty high up off of the ground.

I assume the way you have to do this if you are keeping the solars is to call the solar contractor, have him dismantle his system, get the roofer to do his thing, then have the solar guy reinstall the system.

That will push your payback time down the road a few years.

When I put in my addition I was thinking about solar collectors so I put Grace Ice and Water membrane over the whole south side to make it a little more tolerant of penetrations. I still haven't decided to do the solar thing yet.

My bet is the shingle warranty is void if you put collectors up and your solar warranty is void if the certified solar installer does not do the remove/replace on a re-roof.