Thoughts on Solar

I suspect that most of my NABCEP-Certified colleagues have had this happen - you are on your way to a jobsite when you pass a solar installation that is so painfully bad, that it stops you in your tracks and you just have to go and take a closer look at what happens when Shortcut Solar has botched another job. Follow me into a realm where you never want to find yourself, the horrifying reality of Shortcut Solar at work!

I brake for Shortcut Solar!

Wow, there’s a lot going on there and none of it good.  The panels on the left are facing a variety of trees.  The panels on the right have a significant pitch-up to the south, with a lot of exposure to the wind out of the north.  The cable management there appears to be: let it just hang down.  That middle section is supposed to have 18″ of clearance at the hip given the panels on the adjacent face, but they are actually overlapping the hip!  And how exactly are these attached to the roof?  A closer investigation was in order!

How not to do cable management!

Seriously? Looks like old Shortcut was in a real hurry the day they did this job!  There is a rail there on the high end - surely you could have found some way to use that to get those cables in order - but clearly that wasn’t a priority!

But it was this last image that really got me going.  Checkout this attachment scheme:

I apologize that the image isn’t too clear, but let’s try and break down what is going on here.  At the base in the foreground you can see what appears to be a 3″ or so piece of unistrut that has been cut to length and painted black.  There is no flashing of any sort visible here.  Instead, the strut has apparently been bolted directly onto the roof.  Perhaps those clever fellows from Shortcut Solar drilled pilot holes and squirted in some sealant?  Or maybe not - I mean why go to all that extra effort?

So that’s your attachment, now for the standoff - I know, how about a threaded piece of 3/8″ steel?  You can attach it at the bottom with a channel nut, and then just drill a hole in your aluminum rail and secure it with a nut above and below!  What could possibly go wrong?

Well let’s start with the wind.  When the Santa Ana winds blow out of the North, they will rock those panels, and that long, skinny bolt will flex with the wind.  It is steel and the rail is aluminum, which means that the steel, over time, will chew into the aluminum.  Enough flex over enough time, and that attachment scheme is going to fail - potentially in a catastrophic manner.

(Wanna see what happens when steel defeats aluminum on a roof in the wind?  Check this out!)

 It should come as no surprise that there is a better way to do this!  Here’s our preferred approach:

The picture on the right shows one of the strongest possible combination of solar attachment components you could ask for.  The rail and L-foot comes from Everest.  The 3-inch standoff is from Unirac and the flashing is from Oatey.

Under the flashing is a rounded-rectangular base plate that accepts two, 5/16″ x 3 1/2″ lag bolts.  Two lag bolts gives you twice the strength, and hedges against hitting just the side of a rafter, or a possibly rotted/weak spot.  The 3-inch standoff screws down onto the base, and the Oatey flashing goes over it all, insuring that it will not leak.  The L-foot is bolted to the standoff and is in turn bolted into the rail - which was engineered to accept this configuration.  All components are torqued to the manufacturer’s specification, and marked to indicate that the torquing was performed.

Does it take longer to do things that way?  To be sure.  Does that mean it costs more to do it this way?  Of course.  But ask yourself, which of these approaches would you want on your roof?

We take pride in doing things the right way for our clients so that they can sleep well at night, no matter how hard the wind blows!

And we will continue to brake for Shortcut Solar and call out his subpar work whenever we see it so that you, a solar homeowner, will know what to look out for when you choose a solar installer!

Nothing like a piece in the New York Times questioning the reliability of some solar modules to get tongues wagging and some pointing fingers at “Chinese dumping” while others tell us that solar technology is just not ready for prime time.  To us it raises a different question - does quality sell?

The article, titled Solar Industry Anxious Over Defective Panels, points to installations as close as the Inland Empire, having shockingly high failure rates after just two years of being installed. “Coatings that protect the panels disintegrated while other defects caused two fires that took the system offline for two years, costing hundreds of thousands of dollars in lost revenues.” Wow - that is shocking.  So who made those defective panels?  The reporter doesn’t say.

Nor are any of the problem panels alluded to in this story ever named, citing, in some cases, confidentiality agreements.

Which raises a serious problem with the article: if you cannot identify any of the solar module manufacturers that are having these problems you leave the impression that all solar modules are suspect. (Our analysis on who the guilty party might be is below…)

A quick perusal of the comments to the article reveals the predictable factions: those who echo the Fox News line that solar is a failed technology that only exists because of the Obama Administration’s foolish indulgence in Green Tech; claims that all problems in the solar industry are a result of “Chinese dumping” and the associated China bashing; countered partially by a handful of comments from people who actually know something about the industry.

We find the Chinese bashing particularly problematic - after all, the Chinese are not putting a gun to any project developer’s head and forcing them to use third-tier panels.

Greed is what is causing that.

We have been in business since 2006 and there have always been high quality solar panels available from reputable manufacturers - and they have always cost more than many of the panels offered to us for use in our projects.  Scanning the CSI data (see below) reveals that many projects - including many of the largest projects - were built using those “bargain basement” panels.  Why?  Because it maximized the project developer’s profit.

This is not a new problem, despite it getting a major splash in the “Paper of Record."  Indeed, we wrote in the Spring of 2012 about how the decision by project developers to focus on the lowest cost per Watt “will continue to put undue pressure on quality manufacturers around the globe - whether in the US or China.  Consumer demand for quality is the ultimate way to improve this situation - and that means educating consumers as to what quality means in this market."  A year plus has gone by, but where has that educational effort been?  The need is as great - or greater than ever, but sadly, the NY Times piece fails on that score.  (If you want to read an earlier, and far more comprehensive article on this subject, check out this piece by the great Felicity Carus: Quality Issues Threaten to Give Solar a Black Eye.)

What’s Up in the Inland Empire?

It’s a Friday morning so we decided to indulge in one of our favorite pastimes and go diving into the CSI data to see if we could identify the guilty party alluded to in the NY Times piece.  Here is all they gave us to go on - the project has been in place for roughly four or more years (failed after 2 years, offline for 2 years), located in the “Inland Empire” and its downtime resulted in a loss of “hundreds of thousands of dollars” in revenue.  From that we concluded that we needed to look at systems from 2010 or earlier, in the Inland Empire - which we took to mean anywhere in the counties of Riverside or San Bernardino - and of at least 200 kW.  Those criteria provide us with 28 potential systems, built with solar panels from just seven manufacturers.  Here are our results:

What can we say about these manufacturers?  Well, certainly BP Solar, SunPower, Kyocera and Sanyo would all be considered top-tier manufacturers of solar panels - although BP is exiting the solar industry and Sanyo is now owned by Panasonic.

As for the others, Evergreen Solar was a US manufacturer that filed for bankruptcy in August 2011.  Solar Integrated Technologies was a subsidiary of Michigan-based Energy Conversion Devices which itself filed for bankruptcy in February 2012.  Solar Semiconductor is a vertically integrated systems provider with manufacturing facilities in India.

So who is the guilty party?  No way to know for sure, but a little online searching reveals other problems for one of these companies.  A September 14, 2012 article on the San Diego Union Tribune website documents problems with “Flawed Solar Panels” that were manufactured by Solar Integrated Technologies.  According to the article, the panels manufactured by the company, “had a manufacturing defect that allowed water to seep into crevices of the panels, which in some cases created corrosion and in the worst-case scenario could cause a short that could start rooftop fires” - which sounds a great deal like the problem cited in the New York Times piece.

The Web is littered with sites proclaiming the benefits of solar as a Do-It-Yourself project and we have previously written about the perils of trying to do solar yourself.  But the recent windstorm in Pasadena provided dramatic proof that some things in life should be left to the pros - and solar is one of them.

Take this installation for example - in a lovely part of Pasadena, the previous homeowner designed and installed this system which had a number of significant problems from the get-go.  Here is the view of the site from the north looking south:

The panels that are mounted on the garage go all the way to the ridge, exposing them to higher wind forces.  There are enormous trees to the west and south-east that will provide significant amounts of shade.  The panels on the main roof (that mostly shaded shiny spot in front of the palm tree) are even worse as they are directly facing the tree to the south.  Indeed, from this view from the south, the panels on the main roof are completely invisible:

The array on the garage is pitched at 18° whereas the array on the main roof is completely flat.  Both arrays feed the same inverter which had only one MPPT channel - meaning that this system was never able to function at maximum efficiency.  Not a good design.

Now factor in the force of once-in-a-decade winds and life takes a definite turn for the worse.  The new homeowner called us to come out and assess the damage. Here’s how the array on the garage appeared when we arrived:

It doesn’t look any better in the other direction:

What happened here?

This array was attached to the roof using angle-iron from the local hardware store and simple wood screws, not lag bolts, to keep that hardware in place.  Here’s a close-up showing this homebrew attachment “system":

Those simple wood screws are a poor substitute for proper lag bolts but the previous homeowner didn’t even give his system a fighting chance as he ignored the rafters altogether (even though they were clearly visible) and simple screwed his gear into the plywood under the shingles. The result was as predictable as it was unfortunate:

Moral of the story?  The cost of adding solar professionally continues to drop, whereas the cost of doing it wrong is as steep as it ever was.

It was only good luck that prevented these panels from flying into the neighbor’s back yard.  If the wind had come during the day when the panels were generating power (instead of the middle of the night) the possibility of arcing and fire could have made things much worse.

So please, if you are thinking of adding solar as a DIY project this year, think again and call a pro.