Jump to content

Archived

This topic is now archived and is closed to further replies.

karlInSanDiego

Cold water and hot panels

Recommended Posts

karlInSanDiego

Summer temps get very hot here in San Diego (90+ F), and obviously panels get much hotter.  I won't be able to avoid working during the heat of the day, most likely, so is there safe technique to gradually cool the panels with cold DI/RO water before dousing them?   I'm thinking a first pass across all panels with a fan nozzle from a higher elevation to avoid thermal shock.  I know I saw at least one person in a video in Arizona working panels in the direct sun and dismissing the whole notion that cold water cracks hot panels.  

What is everyone's experience with this?  Is the risk real, and how to avoid it, when you have to work in the full sun?

Share this post


Link to post
Share on other sites
solarpanelcleaningltd

If it’s super hot, we let all the hose out and allow it to warm in the sun. You’d be surprised how much heat it’ll pick up over 100m

Share this post


Link to post
Share on other sites
Pjj

Your air temperature is more than we usually get in the uk but we have cleaned panels in the height of summer without any problems but we do use hot water , I have friends who use cold and haven’t had any problems either 

Share this post


Link to post
Share on other sites
Incheck

Maybe just dont do it at that time of year & diversify to something else like pressure washing? Is it worth the risk to continue cleaning them in sustained heat? Wont be cheap to replace & client would probably appreciate a reschedule if you explain the reasons why. Probably dry so fast that you end up using twice as much water & elbow grease as would normally be necessary anyway?


Sent from my iPhone using Window Cleaning Forums

Share this post


Link to post
Share on other sites
Jordiebarrett

Can you not heat the water? Rather than trying to cool, try to work hot?

Sent using the http://Window Cleaning Forums mobile app

Share this post


Link to post
Share on other sites
karlInSanDiego
20 hours ago, Incheck said:

Maybe just dont do it at that time of year & diversify to something else like pressure washing? Is it worth the risk to continue cleaning them in sustained heat? Wont be cheap to replace & client would probably appreciate a reschedule if you explain the reasons why. Probably dry so fast that you end up using twice as much water & elbow grease as would normally be necessary anyway?


Sent from my iPhone using Window Cleaning Forums

I understand your point.  Thank you.  My intention is to base my work solely on Solar cleaning.  I'm getting into this as my second career, with the intention of working in a pro-environmental way.  So if I manage it right, eventually I'll be driving an electric vehicle, powered by my own home solar, cleaning solar panels to keep them producing at their peak performance.  So in addition to helping customers save on electric costs, it'll be a service to the environment.  And just like solar is only financially advantageous to a point, and many customers have chosen it out of environmental concern, my marketing will reflect that concern as well.

  Of course an income is important, so your advice about diversity in services is helpful, and I will consider window washing and skylight washing as ways to get the business going while I build a solar base.  Although my wife and I have a large glass greenhouse, conservatories are non-existent here in Southern California.  Only a few select museums and businesses have atriums.

I'm trying to prepare for possible stumbling blocks before I encounter them, thus the cold water hot panel discussion.  The suggestions about warming the water are also very helpful, though I must admit, I cannot yet see how that will be possible if I'm expecting to come in, setup WFP with filter driven off of cold water from client's hose bib as efficiently as I can, wash 10-30 panels, break down and go to the next.  That's why I was suggesting a different spray pattern (fan, or even a misting to start) might introduce the cold water to the panel in a way that is more likely to cool the panel more gradually.  Anyway, I think I have another procedural problem to solve, and you've all given me good ideas.  And overcoming problems like this will set me apart from others if I can do so, and use it in my marketing.  Also, helpful to hear that none of you have actually cracked panels (or at least no one who has is speaking of it).  As of yet, the dangers of thermal shock may be a wives' tale, though I won't treat it as such without a lot more research.

Share this post


Link to post
Share on other sites
karlInSanDiego
On 1/14/2018 at 14:05, solarpanelcleaningltd said:

If it’s super hot, we let all the hose out and allow it to warm in the sun. You’d be surprised how much heat it’ll pick up over 100m

Thanks for that tip.  Do you use black hose for that reason, by any chance?  My supplier sent 100' of white, but if black helps, it'll be a useful investment.  I suppose, if I switch to a truck, I could use 2 solar water panels to try to pass all my water throught.  I'll use my infrared thermometer to do some testing with water temp changes and panel temps. 


My filter's coming today, so I'll have a go at cleaning our greenhouse (tempered glass).

Share this post


Link to post
Share on other sites
solarpanelcleaningltd

If thermal shock is a risk for you(it’s really only a dozen or so days a year for us) then perhaps fit an element to your tank to heat the water prior to use.

We use yellow hose, as that’s what the suppliers have and it stands out on pavements etc. avoiding trip hazard scenarios.

 

 

Share this post


Link to post
Share on other sites
Incheck

We advertised solar panel cleaning for the first year or two at the start, we do residential only, and had next to no enquiries or requests for it, maybe 4 at most? So i tried to figure out why. Apparently even if solar panels are filthy they will still work at 80% or higher efficiency. The loss of efficiency is equally countered by the cost of cleaning it. So why would they bother? The cost of cleaning them is the same as what the value of the extra minuscule % of energy would be. Not sure what the commercial market for it is like but i just stopped offering the service, no point taking the insurance out to clean them so cancelled that too so save a little wedge.


Sent from my iPhone using Window Cleaning Forums

Share this post


Link to post
Share on other sites
Tuffers

Hi @karlInSanDiego, I see you wrote that you will be hooking up a filter system to customers taps. How much are these systems? Have you thought about purifying your water at home via an R/O and carrying it in a large tank in your van? Have you got poles long enough? Have you googled solar panel cleaning in your area to get an idea of what others are doing?

Share this post


Link to post
Share on other sites
Pjj
On 14/01/2018 at 22:05, solarpanelcleaningltd said:

If it’s super hot, we let all the hose out and allow it to warm in the sun. You’d be surprised how much heat it’ll pick up over 100m

 

 

 

 

 

I think this this is a very good point for you if it’s that hot where you are the water in the hose won’t be cold for long , Ime also guessing that the water coming out of the tap is probably got the chill off it to ??? Hope the new venture works for you 

Share this post


Link to post
Share on other sites
karlInSanDiego
32 minutes ago, Tuffers said:

Hi @karlInSanDiego, I see you wrote that you will be hooking up a filter system to customers taps. How much are these systems? Have you thought about purifying your water at home via an R/O and carrying it in a large tank in your van? Have you got poles long enough? Have you googled solar panel cleaning in your area to get an idea of what others are doing?

I've got a portable RO/DI system (48lbs. and should fit easily in a hatchback) coming in the mail.  TDS in San Diego can be really high.  Mine today is 242 TDS, but I've seen reports as high as 400-500.  I hadn't really considered bringing my own water in tanks, because the more successful my business would become, the more I'd be stopping in the middle of the day to reload on water, water isn't cheap here in San Diego (we pay an increased rate over a certain allowance per month).  Buying a truck and loading it down with water might make sense for detailing cars, but I'm not sure it would work for solar.  If I got a 500 panel job at a school for example, and I was filtering at home, I'd be in trouble, I think, whereas, with my own filter, and using customer's water, I only have to consider carrying 2 spare filters (DI and carbon).  This means also, I can drive an efficient car to jobs, instead of a 20 mpg truck.  Of course, if I find that I can't get access to water at all jobs, this could present a problem.  I see potential jobs on the flat roofs of large businesses (in theory with internal ladder access) that might be missing water access.

I just invested in a 40' carbon WF pole. 


Yes, I have researched solar cleaning in my area.  Of the 6 who advertise in my area, 2 posted pricing online, and 4 did not respond to my online requests for quotes.  So it looks like they are not hungry for solar panel work.  There is also one fella advertising locally for a flat fee of $65, but I'm not clear if he is capable of doing 2nd story roofs (which I'm currently trying to work out myself, without the cost/time of scaffolding setup).

Share this post


Link to post
Share on other sites
karlInSanDiego
58 minutes ago, Incheck said:

We advertised solar panel cleaning for the first year or two at the start, we do residential only, and had next to no enquiries or requests for it, maybe 4 at most? So i tried to figure out why. Apparently even if solar panels are filthy they will still work at 80% or higher efficiency. The loss of efficiency is equally countered by the cost of cleaning it. So why would they bother? The cost of cleaning them is the same as what the value of the extra minuscule % of energy would be. Not sure what the commercial market for it is like but i just stopped offering the service, no point taking the insurance out to clean them so cancelled that too so save a little wedge.


Sent from my iPhone using Window Cleaning Forums

This is a good point.  Why do some folks pay to have windows cleaned monthly when they don't produce energy at all, or save them money?  If the service costs too much, most people won't bother.  If I can convince them that their $20,000-$40,000+ investment in helping the environment with solar is getting progressively worse at helping the environment, I can work to establish a market, and not as a con, but as a legitimate service.  Many are believing the solar panel sales force who are telling them that it doesn't pay to wash.  Others are believing that spraying them with hard water from a hose (with no agitation) is doing the job (our salesman told us that).  The solar sales force doesn't want to discuss cleaning/maintenance because it puts off potential buyers.  I can tell you that rain doesn't really clean panels properly, and we don't even get rain here in Southern California for most of the year.  The idea that you should never bother cleaning solar panels is just false.  But I do admit, finding a balance of cost to maintain has to make some financial sense to homeowners too.  When I see that a large percentage of installs in SoCal are nearly horizontal and on 2nd story roofs, I can tell you that people are completely unaware of how dirty they are.  So one factor I hope to employ is to use a camera on my pole to assess or prove to them how dirty they were before and after cleaning. 

I do very much appreciate hearing your personal experience.  It's important for me to hear that the market won't just come running to me.

Interestingly, the solar installers were so good at their sales pitch that people need not maintain their solar, that in the 4 years that we've owned it, not one solar cleaner has offered to clean ours.  I've been getting on my roof and doing it with hard water, and they are filthy a few weeks after I've done it each time (partially because I was doing it wrong, but also because it's dry and dusty with lots of pollen and little rain).  San Diego is a sweet spot for solar in the USA, and potentially, when people are educated that there is a need to clean,  it should be a strong market.

Share this post


Link to post
Share on other sites
karlInSanDiego

Of the two who do advertise their prices online, my 36 panel single story home would cost either $228 or $396 for the first cleaning.  In my mind, many people won't go for that even once they understand they need to clean, but I will have to try to find a fair pricing scheme with the right frequency, and I'll have to see how long it takes me to clean (especially the 2nd story, low pitched roofs).

Share this post


Link to post
Share on other sites
Incheck

If it involves working at height and using poles which aren’t cheap you need to be charging. If you were to e.g spend £300 having your panels cleaned, you might only make an extra £300 back off the electricity before they need cleaning again. Do you see what i mean? The cost may cancel themselves out to the point where its pointless. I dont know the exact figures & not trying to put you off at all. My experience offering/advertising solar panel cleaning was a waste of time. Many others may have had success


Sent from my iPhone using Window Cleaning Forums

Share this post


Link to post
Share on other sites
solarpanelcleaningltd

We’re pretty busy but it’s taken time to get there. Did 5 today.

 

You’ll get through di resin at a rapid pace if you use it on site.

 

I would work out the cost of the water, purify at home and pass the cost on to customer. Maybe you’ll use 50 litres for a 4kw system st the most.

Share this post


Link to post
Share on other sites
karlInSanDiego

The filter is this one:  https://shopwindowcleaningresource.com/pure-water-systems/ez-pure.html/

It's a multistage with one 21" x 4" Charcoal/Sediment filter, two 21" x 4" RO filters in parallel for better flow, and one 21" x 4" DI cartridge as a final stage.  So in theory, if I am careful about flushing the RO filters religiously, they'll preserve the DI greatly and keep that cost to a minimum.  The whole thing  carries with a handle.  Not sure how heavy the 45 lb. filter is once it's filled with water, however?!!

Share this post


Link to post
Share on other sites

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.