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Should you wash your solar panels?

incoherency.co.uk

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Re: Should you wash your solar panels?

#241

Post by amluto »

quickthrowman wrote: post #220
amluto wrote: post #72

Earlier quoted context omitted.

There are many different ways to connect solar panels to the inverter. Usually the exposed metallic parts will be “grounded” (bonded to the ground / protective earth / equipment grounding conductor / whatever your jurisdiction calls it at the inverter). But this is an array that looks a bit remote from any structure, and even if the electronics themselves are utterly, perfectly safe, the bonding wire will cause the p…

> Usually the exposed metallic parts will be “grounded” (bonded to the ground / protective earth / equipment grounding conductor / whatever your jurisdiction calls it at the inverter). It’s not usually, all of the panels and also the metal racking must be bonded and grounded. Supplementary grounds are allowed by the NEC, article 250.54 There are zero requirements for supplemental grounds, you could use a single 24AWG…

The OP is pretty clearly not in the US and is not subject to the NEC.

And just because the NEC doesn’t say you need to mitigate touch potentials for a specific installation doesn’t mean that you shouldn’t. The NEC is just a bunch of requirements, not a complete guide to building safe, high quality electrical installations. And there appears to be plenty of guidance from IEEE about this if you feel like paying for a copy of the standard:

https://store.accuristech.com/ecia/products/preview/2085911

The NEC does have plenty to say about grounding for purposes of reducing potential differences in other (non-solar) installations, though. Swimming pools are a notable example (with no specific requirement IIRC to connect the fancy bonding to the Earth at the pool, but a typical concrete pool with NEC-mandated bonding is likely an excellent connection to the local soil).

Amusingly, an inspector could plausibly require an “equipotential plane” per NEC 547.44 if the solar array is accessible to livestock.

Alternatively, from first principles: suppose you are standing with bare feet on wet soil 100 meters from a building. That building has a very nice ground rod array, giving an impedance of 50 ohms from the building’s ground to your feet. Now take a long wire that is insulated except at the ends, connect one end to the building ground, and firmly hold the other end in your hand. How do you feel about this situation? You have a nice wire loop, potentially with area on the order of 100m^2, containing your heart. It can inductively couple to time-varying magnetic fields (e.g. the fields around nearby transmission lines) and it can capacitively couple to other conductors. It can resistively couple to power lines with multiply grounded neutral or to electrified railways or to nearby buildings with old-style (earlier NEC revisions) shared neutral/ground feeds And lightning can strike the array. I think it would be wise to ground the array to earth to reduce the potential difference between the frame and earth.

Re: Should you wash your solar panels?

#242

Post by xandrius »

jhot wrote: post #161
Aurornis wrote: post #78

Washing solar panels is one of the current popular business ideas on social media. It’s an easy pivot for anyone who already has some experience with much harder home repair handiwork involving a ladder. The reason it’s popular is because most people don’t understand the economics at all. Someone can go door-to-door in a neighborhood offering to clean solar panels and making huge claims about improving efficiency so…

I asked a friend with a window cleaning business and they charge about $10 a panel. At that rate I'm tempted to try it but I'm not sure if it's even worth that.

$10/panel to go on top of a roof with the possibility of braking s leg or worse? I'll keep my coding job from my couch :O

Re: Should you wash your solar panels?

#243

Post by lgcmo »

I have worked in the solar industry, and "soiling" is highly dependent on soil, weather, proximity to roads, etc.

And I've seen cases where it made a 30% impact. In other locations, it is a non-issue, but vegetation was a hassle.

Re: Should you wash your solar panels?

#244

Post by TeMPOraL »

gwbas1c wrote: post #158
deepsun wrote: post #133

Earlier quoted context omitted.

I've heard it's pretty standard, their real estate agent should know that (and tell them about it on their first visit).

In the US, Real Estate Agent is a sink-or-swim job. There are a lot of barely competent real estate agents who go through the motions, but otherwise only superficially understand how to do the job. For example, I run an HOA, and agents routinely forget, until the last minute, to come to me for the HOA's paperwork. The state even requires 10 days notice. I've switched to an attitude where I proactively reach out to th…

> Real Estate Agent is a sink-or-swim job. There are a lot of barely competent real estate agents who go through the motions, but otherwise only superficially understand how to do the job.

Language question (ESL speaker here): how does that square? I'd think "sink-or-swim" would imply those still swimming are competent enough by definition?

Re: Should you wash your solar panels?

#245

Post by inigyou »

jaggederest wrote: post #108
the_sleaze_ wrote: post #77

Question for people here: my local power company charges a fee if solar is attached to the grid and is high enough to make installing residential solar impractical. I'm thinking the best thing to do would be put a large battery in between the grid and my home and selectively recharge the battery with the solar. I believe that setup circumvents the fee since the only thing using energy is the battery, as though it wer…

> I believe that setup circumvents the fee since the only thing using energy is the battery, as though it were an off grid setup. Entirely based on your jurisdiction, but that kind of zero-export requires the same permits and connection fee as a full net metering in mine. You can't end run the process by just being sneaky, electrical work needs permits and they'll either make you take it out (!!) or bring it into ful…

There are likely much lower requirements if your system is completely separated, though you'll still have to follow the general electrical code possibly including getting a professional electrician to build or certify it.

Some places don't even allow that, though.

Re: Should you wash your solar panels?

#246

Post by inigyou »

sumtechguy wrote: post #120
the_sleaze_ wrote: post #77

Question for people here: my local power company charges a fee if solar is attached to the grid and is high enough to make installing residential solar impractical. I'm thinking the best thing to do would be put a large battery in between the grid and my home and selectively recharge the battery with the solar. I believe that setup circumvents the fee since the only thing using energy is the battery, as though it wer…

Having just put a battery into my existing system. For the power company I use the answer is no to your question. Many power companies charge that fee depending on the size of panels. Now if you do not hook to their system they do not care (off grid). But if you plug into it then they care and charge for the privilege. Now you could pull particular items out of their grid. Just need the wires and panels to make sense…

In that kind of situation you could work around this legally just by reconnecting loads to the other system as needed. E.g. battery is getting low, better unplug the fridge from the green-painted solar power outlet and plug it into the red-painted grid power outlet right next to it. You maintain the air-gap but still get to load-balance.

Re: Should you wash your solar panels?

#247

Post by dlubarov »

ssl-3 wrote: post #136
dlubarov wrote: post #68

Earlier quoted context omitted.

To add a few more: it's similarly easy to swap cabinet handles, vent covers, outlet wall plates. Fresh caulk is nice too, even if it's a bit sloppy, still beats stained or cracked caulk.

Those are things I've noticed when I've shopped for homes. Mostly, I notice that they look like efforts that were motivated by trying to get a high price, but are limited to being fast and cheap. So while I do note them, my perception of them is not generally positive at all. I'd rather the outlet covers be original and clean than the new, usually oversized covers (with a slight color mismatch) I often find. If I'm s…

I think it's safe to say you're in the minority. Empirically, "fast and cheap" cosmetic upgrades like repainting usually more than pay for themselves.

> I'd rather the outlet covers be original and clean than the new, usually oversized covers (with a slight color mismatch) I often find.

Any task can be screwed up if someone is careless enough, but this is extremely easy to get right. If a standard cover plate fit before, it's trivial to buy a replacement of the standard size and appropriate color.

Cleaning works too, I personally just wouldn't bother cleaning a part that costs ~$0.50.

> When I see sloppy caulk I first think of the time I'll need to spend to dig it all out.

Would you really rather see cracked caulk, which means (a) the original contractor probably used whatever cheap rigid caulk he found in his van, (b) it's been letting water through instead of sealing, and (c) noone cared enough to fix it?

Re: Should you wash your solar panels?

#248

Post by gwbas1c »

TeMPOraL wrote: post #244
gwbas1c wrote: post #158

Earlier quoted context omitted.

In the US, Real Estate Agent is a sink-or-swim job. There are a lot of barely competent real estate agents who go through the motions, but otherwise only superficially understand how to do the job. For example, I run an HOA, and agents routinely forget, until the last minute, to come to me for the HOA's paperwork. The state even requires 10 days notice. I've switched to an attitude where I proactively reach out to th…

> Real Estate Agent is a sink-or-swim job. There are a lot of barely competent real estate agents who go through the motions, but otherwise only superficially understand how to do the job. Language question (ESL speaker here): how does that square? I'd think "sink-or-swim" would imply those still swimming are competent enough by definition?

https://www.google.com/search?q=sink+or+swim&ie=UTF-8

(In case my results are personalized)

> "Sink or swim" is a common English idiom that means a person must either succeed through their own efforts or fail completely, with no middle ground or outside help.

There are a lot of jobs in the US that are easy to get, but many people fail at the job. Typically these are sales jobs where the pay is mostly commission. (IE, most pay is tied to making sales.) The "sink or swim" aspect is that either someone is successful (IE, they make sales and get paid) or fail (don't make sales and thus don't get paid) and move on.

Re: Should you wash your solar panels?

#249

Post by TeMPOraL »

gwbas1c wrote: post #248
TeMPOraL wrote: post #244

Earlier quoted context omitted.

> Real Estate Agent is a sink-or-swim job. There are a lot of barely competent real estate agents who go through the motions, but otherwise only superficially understand how to do the job. Language question (ESL speaker here): how does that square? I'd think "sink-or-swim" would imply those still swimming are competent enough by definition?

https://www.google.com/search?q=sink+or+swim&ie=UTF-8 (In case my results are personalized) > "Sink or swim" is a common English idiom that means a person must either succeed through their own efforts or fail completely, with no middle ground or outside help. There are a lot of jobs in the US that are easy to get, but many people fail at the job. Typically these are sales jobs where the pay is mostly commission. (IE,…

Right, but I understood this to mean you either succeed at this job, or fail and go do something else. Succeeding or failing at individual sales isn't particularly interesting- broken down enough, every job has binary outcome subtasks.

Re: Should you wash your solar panels?

#250

Post by dredmorbius »

Archelaos wrote: post #62
wodenokoto wrote: post #6

> why would you clean them when you're about to sell the house? So they look good and the potential buyer sees something that looks to be in good condition and working well.

I would generalise this a little: The problem with buying a complex item is information inequality. The seller knows more about it than the potential buyer. When inspecting the item, the buyer therefore looks for signs of hidden defects or for evidence that the item is in good condition overall. In this way, cleanliness becomes a proxy for the general condition of the object. Similar mechanisms are at work elsewhere…

Brown M&Ms:

https://www.npr.org/sections/therecord/2012/02/14/146880432/...>

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