Is price always the first consideration in solar panels?

[OffGridInTheCity]

How much is propane in your area?

It was $2.98/gal when I filled them up - maybe 6 months ago.

 

[Solarcabin Channel]

Nope just a big Richard

Maybe you are just a lousy haggler?

 

[OffGridInTheCity]

I'm leasing a 100gal unit for one of the trailers... $100/year. We've used it so little, I first filled it in April of 2022... still have 60 gallons... Absorption fridge at night was the biggest drain

I went 100lb tanks so I can move them around to the house for heater or over to the generator for some kwh or off-property to get them refilled.
The only location we have for a permanent tank would require ~150ft hose from the refill truck - maybe this is OK? not sure. But the other issue is I didn't want to fool with running permanent propane lines from a fixed tank and be involved with permits.

 

[Solarcabin Channel]

It was $2.98/gal when I filled them up - maybe 6 months ago.

Bit higher than we have here in the oil patch at about $2.50.

 

[OffGridInTheCity]

I have to disagree with your statement here. I believe what you have is older 72 cell poly panels and newer 60 cell panels. Panel efficiency has really improved over the last 10 years. When I was in the business I sold, probably every brand panels made at the time. One brand I sold had mono and poly panels of the same wattage that were exactly the same size. About 5 years ago there was a big improvement in efficiency where a typical 295 - 305 watt panel was 72 cells and any 60 cell panel was no more than 260. All of a sudden you were seeing 340 - 360 watt panels in a 60 cell package. True they were mostly monos in that higher wattage but I suggest your same wattage panels are different in age and cell count. If that's the case you might want to check the voltage specs on the larger panels. They are probably higher voltage and lower amperage.

No disagreement / interesting / didn't know this. In any case, I doubt you'll find $70/285w 'newer' poly panels? So for cheap, my point is to be aware of size difference.

 

[sunshine_eggo]

Funny coming from a guy that said "have to keep my wife happy with this shit"

Everything comes with a price!

You've drawn a false analogy. That was a commentary about me, as this is my obsession/interest, not my wife or costs associated thereof.

 

[littleharbor2]

No disagreement / interesting / didn't know this. In any case, I doubt you'll find $70/285w 'newer' poly panels? So for cheap, my point is to be aware of size difference.

Have you looked at Santan Solar and Solar Steals?

 

[OffGridInTheCity]

Have you looked at Santan Solar and Solar Steals?

I purchased 40 x 285w Poly Suntech panelsfrom Santan Solar 2.5 years ago for my emergency stash. These are 9yr old (at the time) and tested 95%+ to spec in comparison to a new mono 285w panel by point both to the sun and comparing amps * volts = watts. ~$70/each.


I also bought 4 x 300w panels for my trailer from Santan Solar - one had a bad diode pack but it was easy to fix.

 

[sunshine_eggo]

I purchased 40 x 285w Poly Suntech panelsfrom Santan Solar 2.5 years ago for my emergency stash. These are 9yr old (at the time) and tested 95%+ to spec in comparison to a new mono 285w panel by point both to the sun and comparing amps * volts = watts. ~$70/each.
View attachment 172904View attachment 172907

I also bought 4 x 300w panels for my trailer from Santan Solar - one had a bad diode pack but it was easy to fix.

LOL... we bought the same panels at about the same time. I only got 36 of them.



T'was an impulse purchase of UL labeled panels with the intent of installing GT solar on the Mesa house, which turned out to be a bust. they're a near perfect Vmp match with my Talesun 330W, so I'll probably use as much of ~5kW as I can as a PV awning to power a 2 ton PV mini-split to offset heating/cooling costs in the Mesa house and will use the balance of them up North for E & W arrays in parallel with my S array.

Cheap shipping since I work about 1.5 miles from them only about $30 worth of gas in the 7.4L...

 

[littleharbor2]

My array consists of 12 185 watt SunTech monos.

 

[SilverbackMP]

i have no input on the question at hand, but an idea. I also have a lot of trees and shading is a concern. I have a location that I think will work well, but I am not sure about shading in the winter. Summer will not be an issue.

I bought a time lapse camera and have it mounted about 15' up and overlooking the general location of where I want the array. I have also considered to mount some on my west facing barn roof which is also in the picture frame. I am giving it 8 months run time and set it to take a picture every 45 min. Then I can see how bad the shading will be and can also see where a better location could be. I wanted to see the shade progression without having to take a picture everyday with my phone. And there are instances where it's cloudy for days at a time and I didn't want to forget. I will look for the camera model if you want (couldn't find the purchase in my email), but that battery life for every 45 min is like 6 month if not more.

This allows me time to do more research, prices to come down/product to improve and determine if this is the best option.

There are online maps that show shadows at any time at any date in the year. You won’t be able to see your trees but you can navigate to any medium sized city near you and look at how the buildings cast shadow.

 

[OffGridInTheCity]

There are online maps that show shadows at any time at any date in the year. You won’t be able to see your trees but you can navigate to any medium sized city near you and look at how the buildings cast shadow.

I use SunCalc - https://www.suncalc.org/ - for detailed analysis. Click down to street level at you're specific location and change calendar / time of day to see sun direction and angles.

For example, my neighbor put up a pool shade structure right on our shared fence and I was able to determine that at a sun angle of 27deg (or lower) I will get a shadow on my panels. Further - this happens from early Dec & Jan - e.g. the 27deg or lower - for portions of the day. By knowing this + tracking PV input I was able to determine it costs me up to ~5% of my PV on sunny days. So no reason to start a feud

Dec 21st at noon.....

 

[Brucey]

You are comparing apples and oranges.

Poly panels are older type panels that were used before mono panels became affordable.

They work and can even work better than mono in low light conditions but poly panels have a shorter lifespan and more significant drop off in production.

"Mono panels can last 30–40 years with optimal care and maintenance. Poly panels last 25–35 years with proper upkeep."

Monocrystalline vs. Polycrystalline Solar Panels (2024 Guide)

Confused about the difference between monocrystalline vs. polycrystalline solar panels? Read our detailed guide to learn how they compare.

www.thisoldhouse.com

Bifacial panels are a new technology and more expensive per watt than a typical mono panel of the same watts. They need a reflective surface on both sides to see the benefits and the testing I read is still inconclusive as to long term benefits.

Where are you finding bifacial 330 watt new for $175 as a price check shows those at around $300?

Bifacial 400W for ~$136+shipping, around $150 delivered in qty of 10+

 

[tomy2]

Regardless of the amount of the credit, you are loosing production, ROI and value in a system that can be grid tied and earn credit but isn’t. Depending on how much you overproduce in the summer you could, despite the rate, offset some or all of your winter use. You are in essence turning down free money from your system and the sun once the grid tie expenses and process is complete.

Consider carefully wasting what you could produce, even if it could just pay for a month a year, that’s a month you don’t have to and after a few years that certainly adds up.

The main problem with a grid connection is that it needs to be inspected. and where I live, the inspector will often see something unrelated that they don't like, which can cost thousands of dollars to change. No grid=no inspector!

 

[Balrog006]

The main problem with a grid connection is that it needs to be inspected. and where I live, the inspector will often see something unrelated that they don't like, which can cost thousands of dollars to change. No grid=no inspector!

An unfortunate but necessary complication to make full use of your system and the POCO.