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Author: derek the solarboi

I've worked in solar for 2014, working everything from install, service, and management. I have a passion for sharing how things work and what people can expect from their systems as they age and need service.

Shining a Light on Lumio

From Eric Peterson at Utah Investigative Journalism Project:

McDole has hired a lawyer and is still battling the company over her claim of roof damage and for giving her what she said is false information about tax rebates being able to offset a third of the $40,000 loan she had to take out.

When McDole heard about Lumio’s tax incentive, she was astounded.

“Where’s my fucking tax break?” she asked.

Sigh. Another day, another large solar company accused of defrauding their customers. The entire article’s very good, go read it and then come back.

I keep getting Pink Energy vibes, here. For better or worse, I’ve been obsessed with the Powerhome Solar/Pink Energy story recently, along with diving into the CEO’s claims and actions over the course of the last several years. Pink Energy, of course, went bankrupt in 2022, after years of customer complaints— similar to those being brought to Lumio. Of course, Pink Energy’s death was brought much more swiftly due to issues with Generac’s solar product at the time, but I tend to think Pink Energy wasn’t going to last, anyway. I’ve seen enough reports of bad training and mismanagement at the lower levels that is really hard to fix, especially when the CEO bragged in his own book about firing 20% of Powerhome staff, every time the performance numbers weren’t where they needed to be1.

Solar is complex. Honestly, more complex than it often needs to be, mostly due to regulatory shit. Changing codes, especially when you’re a company that’s multi-state, can be a nightmare for training designers and installers. And I don’t know for sure what Lumio’s business model is, either, because there’s a ton of conflicting information about whether Lumio’s installer’s are all in-house or if they use a number of contractors (I dare you to try deriving any conclusion from this Reddit thread, for example). Regardless, they started by buying or merging with a number of solar companies. Especially in that situation, quality and customer care becomes a super difficult thing to manage and maintain under the expectation of immediate growth, a problem with most investor-backed companies.

Growth at all costs is extremely costly. And in this industry, growth at all costs for a solar company usually ends up being more costly for the customer. Large solar companies are often able to hide behind well-paid lawyers, flashy marketing, and tedious games of phone tag, where the solar company never tags back.

And again, we come back to the question: Will solar ever get to a place where we’re not identified largely as scammers, and if so, what are the market forces that will finally make it happen? Do we need yet more regulation, this time in sales contracts? Do we need “Nutrition Facts” labels for solar contracts, explaining in consistent terms how if you don’t have the tax liability to get your 30% credit, you’re gonna suddenly be paying way higher monthly bills for the next 20 years? Do we need some faster, state-enforced means of forcing lazy solar installers to come back and fix their fucked installations? Or is this simply an inevitable by-product of the opportunity presented by federal tax credits and grants, seized by salesmen and CEOs with dollar signs in their eyes?

Just stop screwing up my industry, geeeeeez

  1. Own Your Power by Jayson Waller, p138 ↩︎

UL3741.com

Announcement! Are you having a hard time tracking down what inverters and racking systems are compatible with UL 3741? I’ve made a website for that!

https://ul3741.com/

This is a passion project of mine, to categorize all inverters and racking systems that are listed with UL 3741, on a website that’s accessible and easy to navigate. I know of a couple things I still need to add to the site, but it’s pretty fleshed out already, and I’d appreciate feedback on what’s helpful and what you think it still needs.

If you’re a brand and feel like your products aren’t represented properly, please feel free to reach out using the contact form on the website so we can get things straightened out. I want this to be beneficial to both consumers and manufacturers.

Big thanks to John Weaver (aka Commercial Solar Guy) for inspiring this idea!

“Racing” Toward Perovskites – TL;DR

From CleanTechnica:

In a new paper published February 26 in the journal Nature Energy, a CU Boulder researcher and his international collaborators unveiled an innovative method to manufacture the new solar cells, known as perovskite cells, an achievement critical for the commercialization of what many consider the next generation of solar technology.

Here’s the TL;DR – No, perovskites are not dramatically closer to being commercially viable. They found they could reduce oxidation in open air (which is what kills the performance of perovskites over time) by mixing dimethylammonium formate with the perovskite solution before it’s sprayed onto the panel. This allows for retained performance of 90% after 700 hours, up from 300 hours. As the article notes, there are over 8000 hrs in a year.

Still have a ways to go.

Tesla Roof comparisons by Matt Ferrell

Absolutely fantastic video from Matt Ferrell here. He does a pretty fair apples-to-apples comparison between his more typical solar setup and Paul Braren from TinkerTry.com‘s Tesla solar roof installation. Where I often see very abstract cost comparisons to Tesla’s solar roof, this takes a look at the costs and benefits in a ton of different ways. Both systems are definitely higher in cost than your typical solar install, but the comparisons are fair and useful! Loved this.

Fiberglass PV Frames?!

From pv magazine:

“This composite material is used in applications such as wind turbine blades, to withstand wind pressure, vibration and centrifugal force, as well as railway tracks, to withstand the pressure and vibration of passing trains,” a spokesperson from the company told pv magazine. “Fiberglass-reinforced composite materials have been used for over 20 years in outdoor environments and fields with higher load requirements, with countless successful application cases.”

Fiberglass-reinforced composite for panel frames is fascinating on a number of levels.

  • Panel frame wouldn’t need grounded, which is a very weird thing to think about.
  • Would it make the panel heavier or lighter than aluminum frames? Presumably heavier.
  • Not having to deal with any leakage to ground through the panel frame in 20 years might actually lead to better longevity.
  • Then again, I don’t know how fiberglass-reinforced composite will fare after 30-40 years in direct sun. We know the silicon lasts forever if it’s treated well, but will the composite match aluminum’s durability?
  • This would be worse for recycling

What do you think?

SMA Core 1 inverter loses serial number!

Ever had an issue with SMA inverters losing their serial number? Here’s how to fix it!

This is an example of this happening to me recently, and I’ll give some more details below the video, if you’re struggling with this same issue.

I’ve only ever seen this happen on the first iteration of the Core 1 inverter, the -40 model. The symptom is a wifi signal from the inverter that’s showing a “0900” number in the SSID. For instance, in a normal SSID, I’d expect to see the name be “SMA3000XXXXXX”— basically, “SMA”, plus the serial number visible on the exterior inverter label. But when the inverter loses its serial, it makes up a completely different serial for itself, usually starting in “0900”. In my case, I was seeing “SMA0900022963”.

This issue can cause problems with communication and general administration of the device, so it should be fixed, if possible. However, I’ve never seen this issue be responsible for lost power, so it’s a low-level problem, in the grand scheme of things.

The fix for this can only be accomplished through Level 2 of SMA’s tech support (call +1 (877) 697-6283). Level 1 will get your information, tell you your case number, and send you to Level 2.

Level 2 will need to screen-share with your laptop (Windows only), while your laptop is on the same network with the inverters themselves. You need to visit the login page of the inverter, but instead of the ending url being “login” (i.e. “https://<IP-Address-of-inverter>/#/login”), it needs to be “loginadvanced” (i.e. “https://<IP-Address-of-inverter>/#/loginadvanced”).

From there, to log into the “Service” user group, SMA’s tech will need to generate a password from that serial number you saw in the WiFi SSID earlier. In my case, “900022963”. There’s often a lot of confusion from the technician at this part. They’ll be fine, they’ll figure it out eventually. Last I knew, their password generates from the “serial number”, WITHOUT any zeros at the beginning.

Once the Service user group has been logged into, the only thing that needs done is typing in the correct serial number in Parameters->Type Label->Type Label->Serial Number.

Easy peasy, but you’re heavily reliant on that password from SMA for this fix.

Issue Solved: Fronius MPPT1 dropping production

I’ve been fighting with two identically installed Fronius Symo Advanced (10kW) inverters over the last month, and I think I’ve finally fixed it. It’s very strange, and seems to be an issue in the firmware of the inverter, itself.

The installation looks like this. They are two carports (only one is pictured), identically oriented, with north, south, east, and west arrays. The east and west arrays are smaller and hooked up to a Fronius Primo 3.8 on each carport, obviously using different MPPTs for different arrays. The same thing is the case for the north and south arrays: they’re hooked up to a Symo Advanced 10.0 at each carport.

The problem is that MPPT1, hooked up to the north array on each carport, drops off during high irradiance days. Check it out.

You can see when it starts producing in the morning, drops to nothing, then later in the day, it jumps back up and starts producing. Sometimes it takes until after noon, and sometimes, like pictured above, it comes back up when the irradiance dips and MPPT2 produces less for a bit.

This only happens on higher irradiance days with good, bright sun, and on both carports. On cloudier days, both north and south arrays on both carports produce equally, as you’d expect with diffuse sun.

Fronius tech support was no help with this one. We made sure firmware was up to date (fro34310 at the time, for those following along), but beyond that they were extremely confident that there was something wrong with our wiring or our array setup, but couldn’t give me proper direction. It may have simply been the one tech I was talking to, but he was extremely frustratingly not budging on his assessment. It doesn’t help that there are no error codes triggered with this problem.

In troubleshooting, I couldn’t nail any issues to our set up for rapid shutdown devices; everything on site is rated to work with each other and is set up properly. Had some previous issues with dueling RSD transmitters tripping arc faults that I got sorted, so very confident that’s not an issue any more.

When I was onsite, however, I was able to shut off DC to the inverter and turn it back on within about 10-20 seconds, and the inverter jumped up to the proper production on all strings, so it would seem there’s nothing instantaneous in the array that’s causing MPPT strangeness.

Finally, I swapped MPPTs between arrays, putting the south array (highest producing) on MPPT1 and the north array (lowest producing) on MPPT2. After giving it some time, I think this one change solved my issue.

You can see in comparison to the first graph, that the north arrays seem to have no more issues with dropping off in production. The south arrays didn’t have the irradiance on this day that they had in the previous graph, but it’s enough that the north arrays would have dropped off if they were wired as they were originally.

My reckon is that this is directly related to the inverter wigging out when MPPT2 gets 5x or more the production of MPPT1, and only resets when MPPT2 stops rising. I’d imagine that most installations would put the main and highest producing arrays on MPPT1 by default anyway, so this issue would be very rarely seen. If you’re having this issue, try making sure MPPT1 gets the most production between the two, and it might fix it for you.

Weird weird issue.