Solar panel cleaning (lichen, moss etc) - the big imponderable

Alnat1

It'll depend on your water supply. If you're lucky you might have soft water and can use it from the tap. The link said under 75mg/l is ok, checked mine and as I feared it's too high, 104mg/l.

Baldytyke88

My solar panels clean cleaning do to pigeons perching on the TV aerial. I had them cleaned a few years ago for £30 but I have contacted companies 3 times and they don't show up. I have been quoted £100 now, so I am thinking about buying a 7m pole to clean them myself. The pole and pipe is likely to cost me around £100

https://www.ebay.co.uk/itm/168175664548?_trkparms=amclksrc%3DITM%26aid%3D777008%26algo%3DPERSONAL.TOPIC%26ao%3D1%26asc%3D20250417133020%26meid%3D024efdfc7a4b4b4e8b3947ee64257fc8%26pid%3D102726%26rk%3D1%26rkt%3D1%26itm%3D168175664548%26pmt%3D0%26noa%3D1%26pg%3D4375194%26algv%3DRecentlyViewedItemsV2DWebWithPSItemDRV2_BP&_trksid=p4375194.c102726.m162918

jimjames

I find it hard to believe that there will be any difference between using tap water or distilled water once it's on the roof and washed by rain over weeks or months. I've certainly used tap water before and there is no evidence of any mineral residues left on the panels.

Netexporter

Yes, rainwater is a weak solution of carbonic acid, the stuff that dissolved the lime into the water supply originally.

paul991

Depends where you are East Anglia we have a lot of chalk streams so tap water would not be good.

Magnitio

Tap water is perfectly fine. Just clean them when they aren't hot and you know it's going to rain.

Doc_N

https://forums.moneysavingexpert.com/discussion/comment/81907793#Comment_81907793

I wouldn’t worry about it. Any infinitesimally small calcium residue would soon be washed away by the rain.

Doc_N

Just for interest, we paid close on £300 to get our panels cleaned without the use of any chemicals or abrasives about 3 years ago. They were in a pretty poor state, with a lot of lichen, and they were not an easy or quick job. A lot of money - compensated by the fact that there was no damage to the panels, and a 10-15% output increase.

debitcardmayhem

My panels are "Self Cleaning" time will tell 3 years and so far so good.
Mind you they said that about my oven ……

Doc_N

https://forums.moneysavingexpert.com/discussion/comment/81907980#Comment_81907980

Mine were too. They aren't! Well, they might get clean from the rain but that doesn't stop lichen growth, and lichen is the devil's own job to get off.