Mould on solar panels

Hi everyone,

I have a solar hot water system and notcied today that there's a lot of mould on the solar panels. It's been a cold and wet winter in Melbourne so I guess it's built up over the past few months. I'm not too keen to get up on the slippery terracotta tiled roof to clean it, so was wondering if anyone knows whether the mould will be burnt off as the weather gets warmer or whether I will need to clean it otherwise it will affect the effeciency of the panel. Any advice appreciated.

Tony

Find more posts tagged with

Plumbing

Heating and Cooling

Comments

Brad

Hi Tony
Got some moss on mine where the glass meets the frame, that will hose off easily or get burnt off with some decent sun. I would check that it is not leaking if you can get a Melbourne day without rain to check your down pipe for drips, ours gave out at 30 years old and was leaking into the rainwater tank.

Andy_Mann

@AHoy, if you're concerned about roof safety, then fit an eyebolt on the opposite wall to your solar panels, near the bottom (in the mortar would be fine). Attach one end of a long rope to the eye bolt, then hurl rest of it over the rooftop to the other side, & use a gadget like this:

http://www.ebay.com.au/itm/Mountaineering-Tree-Rock-Climbing-Rappelling-Rope-9-12mm-Grab-Protecta-Equip-/401126202449?hash=item5d64fc1c51:g:-~IAAOSwepZXRUOl

Kermit

I would think the heat in summer would be more than enough to burn it off. The roof is a dangerous place - leave it for the pros.

Andy_Mann

https://www.workshop.bunnings.com.au/discussion/comment/1728#Comment_1728

At this time of year when the weather's getting milder, clean panels are a good thing. You're maximising their efficiency, when your own draw during the day is lessened, & you can trickle in some export credit to help offset your non-solar consumption.

Isobel

This page http://www.velocitysolar.com.au/blogs/how-to-clean-solar-panels-2/ says you should get a pro in.

"... utensils may be needed that could cause issues with the panels if not used correctly. Unfortunately moss and Lichen cause large amounts of shading to panels and can have a detrimental effect on the performance of the solar panels."

Andy_Mann

https://www.workshop.bunnings.com.au/discussion/comment/1732#Comment_1732

@Isobel I too have noticed that some solar companies do recommend pro cleaning only, but then, others don't.

I think if people are careful, & use some form of fall protection, then it's pretty straight forward & safe.

Here's a no-nonsense vid that shows how to do the clean, that part, I endorse, BUT wearing skateboard/tennis shoes as the only safety measure, is only appropriate for his particular (low profile, bitumenous shingle) roof. People need to take far more precautions on more typical rooves.

Kermit

https://www.workshop.bunnings.com.au/discussion/comment/63143#Comment_63143

On Whirlpool there's a long discussion about whether you should use any cleaning agent, and whether you should even use water from the tap, with some claiming that both can do damage to the panel.

Andy_Mann

https://www.workshop.bunnings.com.au/discussion/comment/94064#Comment_94064

@Kermit, as with any topic, there're going to be extremes of opinion, & panel cleaning is no exception.

What's to follow, is just my thinking on the matter, & in no way a personal attack on anybody.

To me, solar panels are made to withstand harsh environments & need to be very tough, imagine the turmoil if there was a full on hailstorm, & everyone's panels got wrecked.

The precaution of washing them early morning, early evening to avoid thermal shock, makes a lot of sense. As a bonus, It there's less likelihood of smears being left on the glass.

I agree that cleaning agents need to be chosen with care, but a splash of dishwashing detergent in a bucket of water, won't do any damage & I can't see how it would. Rinsing it off after the clean is common sense, & using a squeegee to remove excess water will prevent smearing. To be doubling sure, wrap a slightly damp micro fibre cloth around the broom head & sweep the panels to remove micro-droplets (if there were any).

The only difference from washing a car windscreen, is that the panels are on the roof, which brings me to the point, who in their right mind would wash their car windscreen with an abrasive cleaner? There's a lot of hysteria out there, & scare mongering by professional panel cleaners, probably to put enough doubt in people's minds, to hire a pro.

AHoy

I ended up not doing anything in the winter. Wanted to see what would happen with some warmer weather. We've had a couple of hot days now and hopefully more to come so have my fingers crossed that the mould will burn off.

AHoy

https://www.workshop.bunnings.com.au/discussion/comment/2412#Comment_2412

Update on this: I had a quote for a new system and the hot water specialist said there was no need to clean the panel as the capacity of the panel far exceeded the storage capacity of the tank. ie it was overkill and being a little bit less efficient wouldn't matter.

AHoy

https://www.workshop.bunnings.com.au/discussion/comment/63781#Comment_63781

Was surprised to read this morning of solar panels bursting due to the cold weather in Melbourne over the weekend - http://www.theage.com.au/victoria/melbournes-frosty-winter-blast-sees-solar-hot-water-panels-burst-around-the-city-20170703-gx3dfd.html

Anyone had the misfortune of experiencing this?

Gerald

Hello All , The mold is a very common black mold and very damaging to Solar panles as it causes hot spots and of course decreases efficiency , we see it often in winery installations and have battled it for 35 years , Its interesting reading all the posts as this subject came up recently in our buisness , we are working on and modfying our coating used to change a surface mold grows on and will keep you informed , from trials on surfaces externally it will keep buildings and tank free of mold for periods of 6 + years and it has a built in feature to help address water staining which is another probelm for panels

Gerald

https://www.workshop.bunnings.com.au/discussion/comment/2412#Comment_2412

Hi , black mold will take hold after 3 to 8 days , it has the ability to do that , Id suggest if you have black mold remove it as it wont burn off , a panel must be clean to be efficient !

Gerald

https://www.workshop.bunnings.com.au/discussion/comment/2412#Comment_2412

The mold matter now a problem being seen on solar panels was no surprise at all , industries such as wine have battled it relentlessly for 40 to 50 years , what is important is to understand that mold can cause damage to a panel so look at removing it , water being used can only cuase a probelm if panels are old and seals are bad ( they sit on a roof so its normal to be exposed to water ) Possibly Google black mold as there are new technolgies about that are addressing mold very differently . or accept mold is a normal part of any enviroment has been since the start of time and we all give it a great place to grow now .

AHoy

https://www.workshop.bunnings.com.au/discussion/comment/64621#Comment_64621

Finally got up on the roof this weekend and cleaned the panels as it was clear it was only going to get worse, not better. Pretty happy with the results. Might get up again next weekend and give the panels a once-over with a microfibre cloth just to make sure there's no smearing left.

Jason

https://www.workshop.bunnings.com.au/discussion/comment/95009#Comment_95009

What did you use to clean them @AHoy? It might help @Mick2 who had a similar problem here - https://www.workshop.com.au/t5/Outdoor/Best-way-to-clean-solar-panels/td-p/21400

Thanks,

Jason

PappaGabba

https://www.workshop.bunnings.com.au/discussion/comment/114014#Comment_114014

The 'mould' shown on the photos looks the same as that on the roof tiles - it is Lichen. Used to live in Canberra where lichen on tiled roofs was common - people would install line of copper wire on top of roof and water running down roof would carry minute amounts of the copper down the roof and slowly kill and remove the lichen. Seems to me that installing copper wire on top of the panels would provide the same result. Probably wouldn't suggest it for those houses that use tank water even though the amount of copper would be minimal. Could also consider washing with a weak mixture of copper sulphate and water.

Child Item