Panel cleaning cost

[Exfarmer]

May have been discussed before, what does the forum think is a fair price per panel for cleaning for say 200 panels plus ( 50 Kw)
I keep toying with the idea of a robot.
European ones seem to be £18,000 up. Still needs operator and pure water source. There is a robot available from Taiwan which starts at £5,000.

 

[rollestonpark]

Our farmhouse window cleaner guy does ours. He's got a tank in his van, he also an ex roofer so knows about walking on farm roofs. But our array is on a newish roof, so very solid.
At the price he charges, it's really cheap job.

 

[lazy farmer]

How much do people think output is improved by cleaning?

 

[Exfarmer]

Our farmhouse window cleaner guy does ours. He's got a tank in his van, he also an ex roofer so knows about walking on farm roofs. But our array is on a newish roof, so very solid.
At the price he charges, it's really cheap job.

We currently have been using a window cleaner, ex army guy who had an 80 foot pole. But I am certain at full reach it was not possible to ensure a good job.
walking on roofs is a non starter for us due to insurance issues.
we were paying about £1 a panel and providing a cherry picker, he provided pure water.
we have been quoted about £2.50 but on condition it is a 3 year annual contract, currently we have been washing only every other year.
i am fairly certain the returns are small unless you have severe algal build up. However once you get that , cleaning can be difficult

 

[Scholsey]

Was quoted 600ex vat to clean 80kw and a ‘system health check’

 

[akaPABLO01]

How much do people think output is improved by cleaning?

I’ve had a large industrial roof go as low as 60% annual output and back to 100% after cleaning.

so on that point you should have an annual output which you should measure over a 2 year period minimum. Some years will be good others bad. Measure the difference over years and if the output declines and gets to say 70% annual average, clean them March/April. This will save on costs, they should require cleaning every 5 years.

the problem with leaving it this long is the grime will be harder to shift. So, look at your figures against 100% production with your losses versus cost to clean. So when the cost is equal to the loss, clean them.

 

[Jim t]

quick question on cleaning solar panels, would it be ok to use a cold pressure washer to clean panels or should I usea hose pipe and brush/sponge ?

 

[Exfarmer]

quick question on cleaning solar panels, would it be ok to use a cold pressure washer to clean panels or should I usea hose pipe and brush/sponge ?

The problem is if you use tap water, unless you have a very soft supply, the calcium salts will build up on the panel, this will get worse over the years, if the water is not squeegeed off, as window cleaners do

 

[Jim t]

Thanks for that, I have soft water it’s the power washer, will I do any damage ?

 

[Scholsey]

The problem is if you use tap water, unless you have a very soft supply, the calcium salts will build up on the panel, this will get worse over the years, if the water is not squeegeed off, as window cleaners do

Is that why the professionals supposedly use deionised water?

 

[Exfarmer]

Thanks for that, I have soft water it’s the power washer, will I do any damage ?

The power washer should not do any damage, I understand that certainly one company in South Norfolk do just that.

 

[Exfarmer]

Is that why the professionals supposedly use deionised water?

Exactly, in this part of the world, you would very quickly see the results of using anything else

 

[Steevo]

Clean them in the rain?

 

[steveR]

Clean them in the rain?

It's what I do.... Soapy water using water from rain butt.

 

[Chickcatcher]

Just for info. Three systems just cleaned total 130Kw 520 panels cost £600 deionised water manual clean on steel roof.

 

[Doing it for the kids]

Just for info. Three systems just cleaned total 130Kw 520 panels cost £600 deionised water manual clean on steel roof.

How did they have access?

 

[Chickcatcher]

Scissor lift for height and safety harness whilst on roof working from above the panels on 15deg pitch roof.

 

[Doing it for the kids]

just had this in. 1st 50kw are on two roofs. Second are on 3 roofs and 9kw on one roof. feels like a lot but maybe I am being tight?

its £119 increase on the last 50 + 9kwh on prices 6 yrs ago - 26% increase?

 

[Scholsey]

Do inverters require any maintainence @Exfarmer?

Got 4 20kwh SMA and had some very strange things happening with sensors etc turned the isolators off on inverters problems stopped, left them off for a hour, was bloody hot in the inverter shed which i guess wasnt helping. All seem to be fine now.

 

[Exfarmer]

Do inverters require any maintainence @Exfarmer?

Got 4 20kwh SMA and had some very strange things happening with sensors etc turned the isolators off on inverters problems stopped, left them off for a hour, was bloody hot in the inverter shed which i guess wasnt helping. All seem to be fine now.

Yes they certainly can. I do not use SMA so have no knowledge of them, but one thing for certain no electronic equipment likes running warm. I have all mine in semi open sheds.
We have had issues but they have always been associated with over voltages coming from the grid or power surges in thunderstorms