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Should you wash your solar panels?

incoherency.co.uk

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Re: Should you wash your solar panels?

#211

Post by arcanemachiner »

brnt wrote: post #205
WalterBright wrote: post #114

Earlier quoted context omitted.

A real estate agent told me that a customer decides to buy/not buy a house as soon as they put their hand on the front door knob. If he decides to buy, he'll look at the rest of the house looking for a reason not to. I.e. putting in an expensive door knob is a good plan!

> A real estate agent told me Whatever you wanted to hear to make them the most amount of money in the(ir) least amount of time. They are the sellers agent. You should not trust them a millimetre further than that. (I bought my current house based on a spreadsheet analysis. Doorknobs are easy to replace, foundations, walls, electric, a lot harder.)

You seem to be assuming that the real estate agent was in the process of selling them a house.

Re: Should you wash your solar panels?

#212

Post by aetherspawn »

quickthrowman wrote: post #14
walrus01 wrote: post #2

It's a bit worrying the author is asking chatgpt about the tingle rather than making sure there's a grounding lug on all the panels and they're all bonded to a grounding rod. The rudimentary nature of the setup makes me think there isn't something like a single conductor 12awg (or euro equivalent) copper wire that bonds to all panels and a basic $30 rod.

The system in question does not have a transformer so a grounding rod is not required as it is not a separately derived system. The equipment grounds should be tied together to prevent any difference in potential though.

I’m an electrical engineer. I just want to explain the hazard with panels.

They are DC, and the voltage is usually very high, between 300V and 600V.

At this voltage you will get a burn, like touching a hot kettle, but because it is DC you will be able to easily “untouch” it.

Yes, the panel frames should all be grounded to each other, and also to Earth in one spot along the chain, as this makes it more difficult to be electrocuted by them because the resistance of the grounding wire is much lower than the resistance of your body, and electricity takes the shortest path.

Re: Should you wash your solar panels?

#213

Post by WalterBright »

SoftTalker wrote: post #167
WalterBright wrote: post #155

Earlier quoted context omitted.

Have you ever driven by a prospective purchase and never bothered to get out of the car? > All were compromises in various ways That's true of just about everything.

No, if we took the time to go to the place, we at least looked at it. I don't remember ever driving up to any property and just turning around. Did we rule looking at something based on photos/descriptions? Yes, certainly.

Photos tend to focus on the house, not the setting. A big deal for me is the relationship of the house to the sun, the neighborhood, the view, privacy, traffic, noise, etc.

Re: Should you wash your solar panels?

#214

Post by simondotau »

WalterBright wrote: post #162
epiccoleman wrote: post #157

Earlier quoted context omitted.

i find it extremely hard to imagine that Donald Trump would have ever been personally involved in the sale of a vehicle at the level that he'd be making decisions about whether or not it was detailed, but I guess it's sensible generic advice

Visit a used car lot. The cars are all clean and detailed.

It’s not that a car needs to be clean per se, but you don’t want prospective owners to be distracted by thoughts of the past life the car has had in the care of another human. Nobody wants to touch the indicator stalk that has layers of dirt and finger grease baked into it.

Re: Should you wash your solar panels?

#215

Post by senderista »

baq wrote: post #201
pton_xd wrote: post #41

Earlier quoted context omitted.

> because human emotions. If I tour a house with pet urine stains all over the carpet, it's only logical to conclude that the owner is likely not maintaining the rest of the house to a very high standard.

That’s exactly how you get a good price though

"Bring your vision!"

Re: Should you wash your solar panels?

#216

Post by WalterBright »

PaulDavisThe1st wrote: post #166
WalterBright wrote: post #111

Earlier quoted context omitted.

"Information inequality" is known as "risk". Risk is inherent in any transaction. That factors into the price: one is willing to pay less the more risk there is, and will pay more for less risk.

Much too simple. Most "risks" have an upside and a downside. In this case, for example, the solar PV system may be working better or worse than the (potential) buyer initially comes to understand. We have huge industries based on selling "risk, but with a huge potential upside" to people willing to pay for access to the potential upside. Many of those customers are not interested in low risk in that context. So "more…

The Black-Sholes equation is an attempt to calculate risk. Of course, risk is difficult to pin down to a number, and different people will assess risk differently.

But that's irrelevant to my point, which was that risk is factored into the price.

Re: Should you wash your solar panels?

#217

Post by noir_lord »

malfist wrote: post #209
noir_lord wrote: post #197

Earlier quoted context omitted.

I’m waiting to see what the sodium packs look like before we do Solar PV (it’s on the list but not near the top so no urgency yet).

Sodium batteries are more grid scale I believe. They require seriously high temps to operate and thats best shared in massive banks

Not just grid scale, already been used in EV’s, less temperature sensitive than Li-ion, way more charge cycles but not quite as energy dense as lithium per kg but that’s not a downside in a static installation.

Re: Should you wash your solar panels?

#219

Post by quickthrowman »

aetherspawn wrote: post #212
quickthrowman wrote: post #14

Earlier quoted context omitted.

The system in question does not have a transformer so a grounding rod is not required as it is not a separately derived system. The equipment grounds should be tied together to prevent any difference in potential though.

I’m an electrical engineer. I just want to explain the hazard with panels. They are DC, and the voltage is usually very high, between 300V and 600V. At this voltage you will get a burn, like touching a hot kettle, but because it is DC you will be able to easily “untouch” it. Yes, the panel frames should all be grounded to each other, and also to Earth in one spot along the chain, as this makes it more difficult to be…

I was just pointing out that a solar installation with only an inverter and no transformer does not need a separate ground since it’s not a separately derived system. An auxiliary/supplementary ground rod is allowed by the NEC (250.54) but it is not required.

Re: Should you wash your solar panels?

#220

Post by quickthrowman »

amluto wrote: post #72
quickthrowman wrote: post #14

Earlier quoted context omitted.

The system in question does not have a transformer so a grounding rod is not required as it is not a separately derived system. The equipment grounds should be tied together to prevent any difference in potential though.

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 conductor bonded to a brad nail or a #6 bare copper conductor bonded to (3) 5/8” dia’ 10’ ground rods. The fact that there are no requirements should tell you something about the necessity of supplemental grounds.

> 250.54 Auxiliary Grounding Electrodes. One or more grounding electrodes shall be permitted to be connected to the equipment grounding conductors specified in 250.118 and shall not be required to comply with the electrode bonding requirements of 250.50 or 250.53(C) or the resistance requirements of 250.53(A)(2) Exception, but the earth shall not be used as an effective ground-fault current path as specified in 250.4(A)(5) and 250.4(B)(4).

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