Removing tree sap from PV panels

Yep. Those citrus based cleaners are great. I've noticed a few lichen spots starting to take hold on some of my panels. I'm wondering if you could add gelatin or agar agar to any liquid solution to achieve the same effect as the sanitizer gel.

Cheers

Justin
 
Sodium polyacrylate is probably better....

Cheers

Justin
 
Yep. Those citrus based cleaners are great. I've noticed a few lichen spots starting to take hold on some of my panels. I'm wondering if you could add gelatin or agar agar to any liquid solution to achieve the same effect as the sanitizer gel.
Cheers Justin
Hi Justin :)
From my experience I would say those "lichen spots" are actually bird shit that has dried out and then goes to that lichen look over time when it rains a bit. We have trees and plenty of birds around. I find a hose off occasionally usually works OK. I have never used anything more than a bit of detergent to clean mine and a broom and not often either.
Jaahn
 
Looks like lichen, feels like lichen, tastes like........

I'm going to mix up some Sodium polyacrylate with some '30 Seconds Roof Treatment' - Benzal-C12-16-alkyldimethyl, chlorides - and make a Gel version - similar to the Alcohol Gel Hand Sanitizer. I can then spray - possibly paint if I get carried away - over the lichen on the sloping panels PV panels. See how we go....

Cheers

Justin
 
Lichen are easy. An old roofer told me years ago to mix Black (actually looks more brown to me) Phenyl 1:3 with water and brush it onto the rooftiles on a stinking hot day. They rain will wash it off over the next few months.
I did that and it worked perfectly - cheap as well and not ruining the gutters.
 
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The solar panels were filthy and spattered with tree sap, dust, sooty mold and given the lorikeets are going nuts probably some nectar with bonus starts of moss and lichen on some of the frames.
Heavy duty car wash, mixed at least 3 times stronger than the recommended "heavy duty" ratio. Wet panels, applied car wash with mop, let soak, scrubbed with one of those extendible soft bristled wash brooms, rinsed clean.
Before:
IMG_20230926_185229_830.jpg



And after:
IMG_20230926_185239_088.jpg
 
Re the black spots that happen under trees. They happen to me too, and come from insect droppings. The only success I have had is using a clay bar.
 
The solar panels were filthy and spattered with tree sap, dust, sooty mold and given the lorikeets are going nuts probably some nectar with bonus starts of moss and lichen on some of the frames.
Heavy duty car wash, mixed at least 3 times stronger than the recommended "heavy duty" ratio. Wet panels, applied car wash with mop, let soak, scrubbed with one of those extendible soft bristled wash brooms, rinsed clean.
Before:
View attachment 227972


And after:
View attachment 227973
Hi.

Have you noticed any increase in the panel output since cleaning?

Cheers.
 
Hi.

Have you noticed any increase in the panel output since cleaning?

Cheers.
I was standing on the roof scrubbing and thought "I should have made notes because Whippet will ask." 🤣
I've disappointed both of us by not paying attention to the generation numbers. We generated 21.3kWh today and our average daily usage is 12.9kWh; that's nice. There's no obvious difference in the power company chart but two days of variable clouds is not a fair average. I'll check our feed in at the end of October and compare it to Octobers of past years
 
I have some rather dirty old solar panels at home that were given to me recently - they will go on my new shed. (it will have its own solar power setup, too far from the house to connect up to our home solar.)
I will measure them before and after cleaning and report back here.
 
I didn’t mention our prevailing westerly winds. One array is on the northeast side and the second is on the northwest of the house. The NE array had a significant deposit of loose dust over the sticky black grime, while the NW only had stuck on residue. The bloke down the street stopped for a chat and said his solar installer put panels flush on his flat garage roof and he’s going to complain and get the installer back to fit a tilt kit. He said the water pools on the flat panels and the dirt dries and sticks.
 
I have some rather dirty old solar panels at home that were given to me recently - they will go on my new shed. (it will have its own solar power setup, too far from the house to connect up to our home solar.)
I will measure them before and after cleaning and report back here.
On another caravan forum the solar guru that most thought knew everything always polished his panels with cutting polish. I thought the cutting polish was a bit much but car polish might make it easier to hose off the dirt and bird poo and lichens occasionally.
I just get on the lower roof, not often now, and hose mine off and use a long handle broom to encourage any spots of stuff to come off. It make me feel they work better. If I check the output quickly, not easy now, it is up instantly due to the cooling effect increasing the panel power. ;)
Jaahn
 
We have a roof mounted antenna that partly shades one panel - but of course that antenna is also a bird perch for a good part of the day - with their associated 'leavings' on the panel. It noticably produces less power than all our other panels. If only it wasn't on the second story roof I'd also be tempted to clean it.

Cheers

Justin
 
Today I got on the roof to clean the gutters and washed the solar panels. I have a small 1KW array that is old ? Possibly 12+years. It has generated 19779 KWh. Not the biggest one , possibly even the smallest around now.
It was doing ~643 W this morning before starting and 30mins after cleaning has settled to ~730 W. The day here is full sun at ~midday and a light breeze.
Jaahn
 
Today I got on the roof to clean the gutters and washed the solar panels. I have a small 1KW array that is old ? Possibly 12+years. It has generated 19779 KWh. Not the biggest one , possibly even the smallest around now.
It was doing ~643 W this morning before starting and 30mins after cleaning has settled to ~730 W. The day here is full sun at ~midday and a light breeze.
Jaahn
12 years ago you were no doubt getting the 60c FIT - your system has paid for itself severals times over !

Cheers

Justin
 
@Whippet I apologise. I know I said I would update you on efficiency pre and post scrubbing but I haven't. I decided there were significant variables that would invalidate the numbers, the two most significant being that the teenager joined the army and moved out and our old gas hot water system died and was replaced by an electric unit.
I thought of this today as I read our latest electricity bill. Last February we were running the old gas water heater. This February we have the same three adult residents and the new electric water heater. This time last year our average daily usage was 5.1kWh, this year our average daily usage has jumped to 10.5kWh which would be the electric water heater. We have three adults in the house and apparently the average daily usage for two people in our area is 12.36kWh. 😲
I'm quite certain that this time last year the solar panels hadn't been cleaned in well over a year rather than within six months. Our current daily solar export averages 14.9kWh (from a 4.5kW array). 😁 We must be doing something right for reducing our greenhouse emissions. I like getting bills that credit me.
 
Also the tree that was contributing black sooty mould to the solar panels got sick enough by last November to be dropping 6m limbs and was declared dangerous and removed by the council. My BiL celebrated by washing his car for the first time in about 8 years and reckons powdered laundry detergent was excellent for scrubbing the black grime from his allegedly white car. I guess that counts as some kind of cut and polish. 🤣
 
THe other annoying quirk/ripoff in the system is that when you install solar and start selling to the grid at the miserly rate they give you the power company increases the rate they charge you for whatever you buy from them, this to a suitably stupendous rate

WHen I challenged them was told that „the Govt sez we have to“ which sounded like a barefaced lie

ANdrew
 
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