Hi. I was wondering if any solar PV installers on here recommend that their clients have their Solar panels cleaned? If so, how often?
I started a solar panel cleaning company on the Gold Coast at the start of 2014 and I've found that very few people who have a system installed know the benefits of keeping them clean. I have found annual cleaning generally gains over 10% in efficiency which means the gains the client receives greatly outweighs the cost of having them cleaned.
Cleaning Solar Panels.
(28 posts) (14 voices)-
Posted Sunday 19 Jul 2015 @ 11:41:26 am from IP #
-
7 years and you live in Brisbane.... Wow thats unheard of! My brother lives in Chermside and I get around 15% when I clean his annually. Don't have any problems with bird and Bat poo? I find that gum leaves leave a really sticky, dirty residue. You should try cleaning them yourself and compared before and after readings (safely of course, follow the proper shut down procedures for your system and I recommend NOT using any chemicals). I normally find that I don't get much more than 20% even for new clients that haven't had them cleaned in years, i believe this is because the panels self clean to a certain extend (kind of like your car when it rains)
Posted Sunday 19 Jul 2015 @ 12:44:30 pm from IP # -
Sunshine
Memberwhat's unheard of? living in Brisbane for 7 years? the readings I have compiled are from brand new, when the panels were clean, so there is no need to compare the readings before and after.. they get dusty at times after a period of no rain, but are clean after rain
Posted Sunday 19 Jul 2015 @ 1:32:58 pm from IP # -
Sorry Sunshine, I meant the fact that you have not lost any efficiency in 7 years! What brand are you panels and do you know what angle they are on? I'm really interested in your set up!
Annette. A lot of clients have solar monitoring software now which makes it easy to compare. Also most inverters have a digital display so we are able to get a before and after reading if it's a clear day. Obviously we have to take in account the time of the readings so we can compare Apples with Apples.
Posted Sunday 19 Jul 2015 @ 2:06:07 pm from IP # -
Chippa2014
MemberI live on the gold coast and have cleaned mine twice. Only because we had a number (50-60) of cockatoos perching on trees at the back of the house who'd fly over and for obvious reasons cleaning was required.
I've had my panels up for 5 years and I'm not seeing any decrease in efficiency at all. If anything the last 2 years have been the most productive.
Panels are Suntech STP300-24/Ve. Claimed NOCT 45C+/-2C, I know its darn hot on the tin roof and we constantly see max power 218W per panel.
Rather happy with our investment.
Posted Sunday 19 Jul 2015 @ 11:17:33 pm from IP # -
Sunshine
MemberSpicknspan Solar,
They are Schott panels at around 27 degree angle.. they are one of the best in the business. they have tested Schott panels after 26 years in Germany and found they were still putting out over 90% of original output. If anything the solar production has actually increasing slightly rather than decreasing as the last couple of years I have had record production figures over several months.
Posted Monday 20 Jul 2015 @ 12:07:13 am from IP # -
I wouldn't object to the thread remaining but the OPs avatar should be deleted although no forum rule appears to have been broken. Maybe make a forum rule that an avatar with a business name can only be used after a set number of posts. 100 post might be ideal as a lesser number may only encourage frivolous posts.
There is a history of new posters using their avatar as advertising and after a few posts, they disappear but their avatar remains.
Posted Monday 20 Jul 2015 @ 3:06:57 am from IP # -
Hi. Im not here to spam or promote my business and i'm more than happy to remove all links to my business if you like. I didn't want to start a fake Avatar, I wanted to be transparent with who I was, hence the reason I used my business name as my avatar. After a lot of research on the net, I found very few forums and those i found were very dated.
I am very interested in what the majority of solar install companies recommend, and their opinions regarding cleaning solar panels and also annual or biannual inspections of leads, isolators, mounts and the panels themselves.
I am more than happy to answer any question regarding my experience.
Regards Ben.
Posted Monday 20 Jul 2015 @ 5:24:50 am from IP # -
Lance
Key Master -
Bushwalker
MemberWhat happened to the 'new' forum, Lance?
Wouldn't it be better to just swap over rather than mod this one, or is there a problem?
Posted Monday 20 Jul 2015 @ 12:34:28 pm from IP # -
I've installed hundreds of systems. Unless the pitch is under 10degrees I have not noticed any difference in production when they are cleaned.
The only place I have heard that cleaning them is good, is from cleaning companies. Although I am happy to be proven to be incorrect.
Posted Monday 20 Jul 2015 @ 11:13:17 pm from IP # -
Johnnojack
MemberI have always cleaned mine, probably 4 or 5 times per year. Hard to notice any difference in output when they are just a bit dusty. (before and after inverter readings) but when they have been trashed by mobs of circling cockatoos the output will jump up about 100W (1400W system). Even that is not 10% but I think it is worth doing. Having to pay someone else to do it would change my thinking I'm sure.
Posted Tuesday 21 Jul 2015 @ 1:18:41 am from IP # -
Lance
Key MasterBushwalker said:
What happened to the 'new' forum, Lance?Wouldn't it be better to just swap over rather than mod this one, or is there a problem?
Not sure what's happening with it, I don't do the site building, I think it is on the list, but the integrated member database/shop/website logins is the priority at the mo.
Posted Tuesday 21 Jul 2015 @ 8:07:28 am from IP # -
I'd recommend cleaning them at least once a year, perhaps when your get routine maintenance performed. Here in Adelaide there are a range of panel cleaning companies for this purpose. There are also a few panels on the market now that are self cleaning!
Posted Thursday 23 Jul 2015 @ 4:11:04 am from IP # -
David
MemberI cleaned mine last year during the summer when the weather was great for several days in a row. Fact is the difference was negligible and they had not been cleaned for 3 years before that definately less then 0.5% improvement rain cleans them about the same, complete waste of money unless there very maybe very flat indeed. Cleaning for performance is mostly rubbish.
Checking system to ensure everything is in good condition and no parts need replacing or tightening different issue.
Posted Thursday 23 Jul 2015 @ 5:41:00 am from IP # -
johnmath
MemberI leave my solar panels out in the rain when I want them cleaned. As long as the panels are steep enough that water doesn't pool on the lower edge and subsequently let muck obscure the bottom cells (>10 degrees), a small amount of dust on the panels can actually increase output at low insolation angles.
Posted Thursday 23 Jul 2015 @ 1:00:02 pm from IP # -
Benny
MemberI've cleaned mine a few times and not seen any significant increase except for a few minutes while they are still cool from the water. I don't have any problems with bird droppings - just dust.
If cleaning gave any real benefit - rather than just anecdotes, then why aren't cleaning companies showing charts with the results clear to see. Daily production for say a month either side of the cleaning day. If it were this clear cut they'd be showing the proof.
If a 2kW system produces 9kWh/day at an import cost of 26c/kWh then its worth $854 per year. I know it different if you export and get higher (or lower) FiT. I've seen quotes of $10 per panel, so $100 for 2kW ? So to be worthwhile the cleaning would have to increase output by 100/854 = 12%.
Posted Friday 24 Jul 2015 @ 8:46:06 am from IP # -
Unfortunately showing daily results a month either side of cleaning would not be an accurate way to monitor the results as kWhs change dramatically from week to week depending on weather. The best way I've found to measure results is to record readings at exactly the same time of day on perfectly days for 2 weeks before and after.
Also I would like to clear up at myth, solar panels are not more efficient when they are cooler. Generally the optimal temperature for panels is 25degs. Often in winter the efficiency will go down after a clean and not show the results until they reach the original temp.
Benny you are right when you say that those people with smaller systems will be out of pocket in the long run. Quite often clients with 1 - 2 kW will not regain the cost of a clean, but you have realise that cleaning is only part of the service. We don't just clean, we inspect panels, mounts, wiring, isolators (I'm still finding recalled isolators still in service) and inverters. I've lost count of the number of systems I found with major problems.
Certainly I've come across a number of systems that stay very efficient without any maintenance but I''ve also came across systems that have been only up for 1 year that were filthy. I was on a pitched roof in Ashmore on Monday and I couldn't believe how dirty they were for their age, I wish I could post a picture on this thread.
I'm not here to tell people to get their panels professionally cleaned, by all means if you can inspect and clean your panels SAFELY yourself, do it! You will soon get an idea how often is best for your system. Annually is normally more than sufficient.
Posted Tuesday 4 Aug 2015 @ 10:07:06 pm from IP # -
Hi Natimuk solar, benefits vs cost obviously varies greatly, I've heard some companies charging $250 just to clean a 5kW system. I highly doubt the benefits would ever out way the cost. In contrast our price on the Gold Coast would be $100-$120 if it was a single storey home and that price includes an inspection, testing and minor repairs such as fixing loose cables, tightening mounts and re-siliconing isolators etc. If we only gained 5% in efficiency the client would be better off.
Do the panels you use say anything about warranties and maintenance? More and more manufacturers are now stipulating that the panels must be maintained otherwise the warranty is voided. Have you ever had any dramas with warranty claims because there wasn't a maintenance record?
Posted Tuesday 4 Aug 2015 @ 10:28:07 pm from IP # -
I think the cleaning is unnecessary. The claim of a 5% gain is very optimistic.(possibly fanciful)
However, the other items offered are a good idea.
Posted Tuesday 4 Aug 2015 @ 11:31:31 pm from IP # -
David
MemberNatimuk Solar said:
The other items offered are a good idea.+1.
As for warranty inspections the main culprit appears to be TVS, they use this as a get out of warranty, while producing ongoing revenue. ACL (Australian Consumer Law) does not allow them to truly walk away but their warranty terms allow them to make it hard to get warranty without going through protracted effort and time.
If a system is installed properly/well, using products that really are fit for purpose, there's no reason why it should want/need more than an occasional inspection.
Posted Wednesday 5 Aug 2015 @ 5:08:19 am from IP #
