It just snowed in Michigan. 8 Inches

[Sunking]

Ditto absolutely no reason to shut it off.

[J.P.M.]

panels are like blacktop. sun thaws out blacktop, sun thaws out panels. gee whiz, its heat.

Since you brought it up:

Saying a panel is like asphalt because they're both sort of black is like saying a turd is like a brown shoe because they're sort of the same color.

Panels are not asphalt. Try driving on a panel. Or getting electricity out of a roadway.

Asphalt doesn't thaw.The petroleum stuff holding the aggregate together gets a bit softer as the temp. increases and the petroleum stuff may get less viscous, and some of the lighter aromatics in the petroleum may sublime "off", but it doesn't change phase as "melting" would imply.

Also, to say panels thaw out sort of implies they melt, as in changing phase. Unless panels are made of material that changes phase at usual panel temps., like some type of eutectic material, they are usually and already in the solid or frozen phase and stay that way. They don't get more or less frozen as they heat up/cool down. The H2O in the solid phase on a panel may thaw and run off as a result of the energy added/transferred to it, or H2O in the liquid phase on a panel may freeze from heat loos via thermal radiation to a colder environment, but the panels don't thaw. They simply gain or lose heat.

No, it's radiant energy that's responsible for most of the temperature changes were talking about here. It's also thermal radiation that's at least partially, if not mostly responsible for panels cooling down.

The greater the absorbance of radiant energy in the solar wavelengths, the more radiant energy will be absorbed and the warmer an object will become. Heat as described by an object's temperature relative to its surroundings is the result, not the cause of energy additions or subtractions. .

Take what you want of the above. Scrap the rest.

[SunEagle]

are you kidding? I live in the north country, northern Wisconsin. it warmed up to -10 yesterday. but there was bright sun.... solar panels did thaw out,, 2 inches of fresh snow melted off. minus 10 f colder than your florida freezer

I am glad they thawed out for you.

Oh, I haven't always lived down here in Florida. I came from the North East and while it might not have been as cold as Wisconsin ( I have been to Marinette a few times in the winter) we did get a lot of snow which is never fun to drive in.

[Sunking]

panels are like blacktop. sun thaws out blacktop, sun thaws out panels. gee whiz, its heat.

You are joking right? There is no comparison between the two. Black top is a thermal mass with earth as a Heat Sink behind it.

[SunEagle]

You are joking right? There is no comparison between the two. Black top is a thermal mass with earth as a Heat Sink behind it.

maybe he mounted his panels on his driveway.

[Sunking]

maybe he mounted his panels on his driveway.

Perhaps. I just cannot understand why it is hard for someone to understand if a panel is shaded, dirty, or covered with snow the power falls off a cliff and becomes useless. It defies common sense. With a username that starts with dr makes one think the person has an education and should understand basic physics. My wifey is an MD and her username is drB, and yes the B means what you think. A solar panel is a bit like a bridge. It will freeze first long before the road does, and the last to thaw.

Does give me an idea though for up sale to yankees. Remove the Blocking Diodes and backfeed the panels with DC to generate heat and de-ice the panels.

[J.P.M.]

Perhaps. I just cannot understand why it is hard for someone to understand if a panel is shaded, dirty, or covered with snow the power falls off a cliff and becomes useless. It defies common sense. With a username that starts with dr makes one think the person has an education and should understand basic physics. My wifey is an MD and her username is drB, and yes the B means what you think. A solar panel is a bit like a bridge. It will freeze first long before the road does, and the last to thaw.

Does give me an idea though for up sale to yankees. Remove the Blocking Diodes and backfeed the panels with DC to generate heat and de-ice the panels.

I thought of that long ago in a far away land called Buffalo. Too busy as and engineering slug/wage whore to do much with it. Kind of a "you could just do this and - poof- a miracle happens" kind of B.S. (non) thinking tree huggers seem to excel at.

[J.P.M.]

You are joking right? There is no comparison between the two. Black top is a thermal mass with earth as a Heat Sink behind it.

The way to analyze the situation is with the concept of a heat balance. Heat transfer 101. Set boundary surfaces. Then, consider as many inputs, forcing functions and variables that describe how energy crosses the boundaries as seem relevant. Quite simple to model actually.

[bcroe]

Perhaps. I just cannot understand why it is hard for someone to understand if a panel is
shaded, dirty, or covered with snow the power falls off a cliff and becomes useless. It defies common sense.

Does give me an idea though for up sale to yankees. Remove the Blocking Diodes and backfeed the
panels with DC to generate heat and de-ice the panels.

Tried that years ago. You don't need to remove the bypass diodes, no blocking in most panels. I bumped
the DC power up to 3 times the panel rated output (250W/750W) but that snow never moved.

Guess most people don't understand conservation of energy, it either makes the trip
or gets lost on the way. No recreating it where you wish it was. Bruce Roe


PVmelt.jpg

[Sunking]

Guess most people don't understand conservation of energy, it either makes the trip
or gets lost on the way. No recreating it where you wish it was. Bruce Roe

No guessing about it. it is a fact, a sad fact. US public schools quit teaching basic science and math skills decades ago. Political Correctness ruined the USA education system. It was too hard for some students and hurt their poor little feelings. Some poor little kids could not understand the simple law of Conservation of Energy. To fix that problem, they made the rest of the kids as dumb as the slower kids so they did not get their poor little feelings hurt. Works out pretty good for the government. Makes it real easy to control masses if they are ignorant.

[J.P.M.]

No guessing about it. it is a fact, a sad fact. US public schools quit teaching basic science and math skills decades ago. Political Correctness ruined the USA education system. It was too hard for some students and hurt their poor little feelings. Some poor little kids could not understand the simple law of Conservation of Energy. To fix that problem, they made the rest of the kids as dumb as the slower kids so they did not get their poor little feelings hurt. Works out pretty good for the government. Makes it real easy to control masses if they are ignorant.

And now they're all as dumb as doorknobs. Scary part of that for me is that I don't see their teachers or parents being any better at using their heads. That whole situation doesn't seem to raise the probability of things improving. In the end, it's all another example of how entropy governs everything, even human interactions.

Rant mode off.

[Sunking]

And now they're all as dumb as doorknobs. Scary part of that for me is that I don't see their teachers or parents being any better at using their heads

JPM you and I are Baby Boomers, the last generation to receive a proper education before the Johnson administration hippies started dumbing down the US education system. We traded education for peace, love, sex, and drugs. We allowed it to happen. When we graduated is equal to a 4-year college grad today in a public university. Today to recive a good education requires a private school and university free of government controls.

It can be fixed and starts with throwing the government out of schools.

[J.P.M.]

JPM you and I are Baby Boomers, the last generation to receive a proper education before the Johnson administration hippies started dumbing down the US education system. We traded education for peace, love, sex, and drugs. We allowed it to happen. When we graduated is equal to a 4-year college grad today in a public university. Today to recive a good education requires a private school and university free of government controls.

It can be fixed and starts with throwing the government out of schools.

I believe that's part of it, but I'm also of the sincere opinion that it's more complicated, deeper and a lot more sinister than that.

One thing, among many I try to remember is to stay mindful of how much I probably sound like all the old farts who ranted at me when I was 20 yrs. old or so and who lamented the good old days and how things went in the toilet when the godless hippies took over.

History and some parts of the social order somehow seem more cyclic now than I once viewed them..

But I still think we're screwed.

[Sunking]

But I still think we're screwed.

Most likely a revolution to throw the government and teachers unions out of the education system. Possible a world war which is not far off.

Look it took 4 decades for the public education system to get where it is today. You and I know that, we lived and seen it happen. My thinking, not my idea, is it will take a state like TX to reject Federal money for public education. Do that and you can throw away all Federal requirements and the Unions out on the street. That is exactly what private schools/universities and home schooled have done. Both educators and students need to be on a Merit System.

It would take at least two generations to fix.