Life expectancy of PV panels

[caribconsult]

Awesome! I think Enphase makes some quality stuff and they stand behind it. I have had nothing but good things to say about their Caribbean support team...they have been 100% helpful. For reasons unknown, the Envoy would not connect to my house wifi to get on line and report the data...well, it would and it wouldn't...connected and disconnected erratically. I finally did away with the wifi link by putting an EOP adaptor right in the Envoy box where there's a receptacle just for it, and using that to get to the router at the other end of the house. Works perfectly and connected itself as soon as I plugged it in. I don't know how much better than that you could do.

It's good to hear that bigger and more powerful solar panels are emerging. All of it...batteries, controllers, inverters, etc, will get cheaper and better as time goes on, because it's the future for many, particularly those that get a lot of sun, as we do. Use it!

 

[gadfly56]

We spec the Envoy in every Enphase system we put together; we are hopeful that we will be able to get Enphase micros again before too very much longer.

My company has a partnership with SunPower; SP just announced a 400W residential module, and there are 395W commercial modules rolling out soon.

Are these 395/400 watt modules occupying the same footprint as the 75 watt modules mentioned from 1995?

 

[electrofelon]

I can't see how that makes any sense. Unless you have a storage system and are completely off grid and depend on the output being at a certain level to meet your electrical needs, at least on an average basis, what is the driver for replacement? At 25 years, the panel costs are fully sunk and whatever your're getting really is free. Why incur capital costs at this point? For what kind of gain? 10% or 15%? That would never meet any kind of reasonable ROI.

I agree with you from an investment standpoint, and certainly the majority of people have that in mind when investing in a PV system, but lets remember people do things for different reasons. As an example, for myself, I hate monthly recurring payments. Makes me feel like a slave. I have money now, I am healthy and have work and can work. I would rather invest in a solar system now and not have to worry about a monthly electric bill for the next 30 years. It makes me feel more flexible and secure.

 

[jaggedben]

Are these 395/400 watt modules occupying the same footprint as the 75 watt modules mentioned from 1995?

They are probably 2-3 times the area (per panel, not array). i.e also 2-3 times more efficient.

 

[romex jockey]

Old PV modules were donated to the PV testing lab at Arizona State University as they were interested in the differences between "good" and "poor" modules.

so there are studies out there then.....~RJ~

 

[ggunn]

Are these 395/400 watt modules occupying the same footprint as the 75 watt modules mentioned from 1995?

The 395W commercial modules are 81.4" X 38.9". I don't know the dimensions of the 400W residential ones.

 

[gadfly56]

The 395W commercial modules are 81.4" X 38.9". I don't know the dimensions of the 400W residential ones.

What were the old 75 watt panels? I'm trying to understand how much more roof real estate is involved.

 

[ggunn]

What were the old 75 watt panels? I'm trying to understand how much more roof real estate is involved.

I have no idea; they were before my time in the industry.

 

[Zee]

I have no idea; they were before my time in the industry.

In 2001, we installed lots of 100 or 110 watt panels.
26x58 inches = 10.47 square feet.
100W/10.5 sq ft = 9.5W / sq ft


Today, panels are 39x66" = 17.88 square feet.
Newest panels are 320 W. (premium SunPower and LG panels will be 365W......... i believe)
320W/17.9 sq ft = 17.9W / sq ft

In 18 years, panel efficiency has gone up (17.9/9.5 = 1.88) 90%

 

[Zee]

I bet the 75W panels were ARCO solar or Siemens and had circular cells or half circles. Just my WAG.

 

[Zee]

I am told the fundamental technology invented by Bell Labs 60 or more years ago is basically unchanged: crystalline silicon cells.
As a result we can observe PV panels operating well on remote mountaintops, etc for decades.

To my knowledge most of the systems i installed as a grunt in 2001 are still fine. (Usually inverters and batteries fail.)
I have gone back and serviced them and customers are often convinced they need to replace but i advise against it. Usually I just add to it.
Usually i will just re string the panels to "high V" 600VDC and get them a modern, grid tie, no battery inverter.

 

[BillK-AZ]

I bet the 75W panels were ARCO solar or Siemens and had circular cells or half circles. Just my WAG.

Photos of the old modules

 

[Zee]

Photos of the old modules

Nice.
Oh wow, you can see the J box "burning" through on 3-4 of them.

(Oh and I see now, you had mentioned they were Arco solar/Siemens)

 

[caribconsult]

On another note, if you are using Tesla's PW system, check your firmware date in the app...you may be using outdated versions behind and the versions don't all function the same way. We had trouble getting our off-grid system updated because they needed to have the grid running into it, which sounded like BS and we didn't leave it on indefinitely because we didn't sell back and as a result they tried to upgrade it remotely and it fell apart. No accurate readings on the app, nor the GUI access via their own TEG wifi, then no power coming out untess grid was on, so essentially running on grid, tesla is frozen. Fortunately we were referred to one of their best diagnostic engineers and he, along with me disconnecting certain plugs inside the gateway, managed to revive the system and connect to it and upgrade the firmware to the latest version and what a difference in performance. The older version we were using would kill the PV array completely when the battery was full, then let the battery drain for perhaps an hour, then switch the PV array on and hope there's enough sunlight to recharge the battery, when it should have been left off once charged and all necessary solar to house. It doesn't do that any longer. Once the battery is charged, all PV output goes directly to house. Correct. Cell communication seems more stable but I use the ethernet via an EOP adaptor and that's what the gateway uses to report. Grid is basically off.

 

[BandGap1.1eV]

There were systems installed under the Carter administrator across the country ad part of a proof of concept. One of them is in Beverly, MA and was still functioning well into the 2000s.

Solar – Dr. John W. Coleman Greenergy Park

In 1981 Beverly High School was one of eight sites in the United States that then President Carter chose for a solar panel installation. Now called the Dr. John W. Coleman Greenergy Park, the site…

www.beverlyma.gov

Original Solar Power Array Keeps Proving Green Future - Ground Report

A four acre solar panel array commissioned by President Jimmy Carter 28 years ago, still powers Beverly High School in Massachusetts. According to the Director of the non-profit Solar Now, who is responsible for the facility, it is the last remaining functional field of its kind in the US, from...

www.groundreport.com

With the rate of change of the PV equipment technology, codes, and standards, you reach a point where it no longer makes financial or technical sense to keep repairing a system if the inverter goes down or a module breaks.