[Luckenwalde (Teltow-Fläming), Germany]

A few apparent Nanosolar Utility Panel mechanical failures were observed.

From Nanosolar 1.1 MegaWatt-peak Solar Plant

Last year in Nanosolar Summer Solar Speculations, I was wrong to doubt a photo showing further progress on the 1.1 MWp (MegaWatt-peak) solar farm located in Luckenwalde, Germany. With the return of EU PVSEC to Hamburg, a side trip outside of Berlin was once again on my agenda.

Arriving at the site late on a humid afternoon, I expected to take a few photos and move along. As I hiked back via the public trail surrounding the retired landfill, I noticed a few PV (photovoltaic) modules were concave instead of flat. I managed to capture three such modules in the photo below. After those, I noticed more concave modules during the visit and reviewing my photos later.

From Nanosolar 1.1 MegaWatt-peak Solar Plant

The frameless, glass on glass structure of the failing modules were bowed towards the ground indicating cracked or broken glass adhering to the laminate. I thought of a few plausible explanations for the failures:

• module manufacturing defects
• damage caused during shipment or handling
• damage caused by faulty assembly of the arrays

Using field data from thin film glass/glass installations, the poster, “Lessons Learned Regarding Failure Modes of Glass/Glass Modules in the Field” by Forrest Collins and Beth Copanas, juwi Solar, Inc., presented at the U.S. Department of Energy (DOE) Solar Energy Technologies Program, Photovoltaic Module Reliability Workshop, developed a comprehensive Installation Company Module Failure Mode Classification scheme with five (5) categories:

• Shipping/Packaging
• Installation and Handling
• Diminished Module Output
• Intrinsic Module Damage After Deployment
• Externally Caused Module Damage After Deployment

In “Nanosolar CIGS, revisited: ‘We’re not competing with each other, we’re competing with crystalline’” by Tom Cheyney at PV-Tech.org, Nanosolar CEO Geoff Tate said:

He also revealed that the performance of the 1.1MW system operating at a landfill in Luckenwalde, Germany, could be better. “A lot of those panels were preproduction, and we’ve made many improvements on performance and reliability. For that project, the performance is good but it’s not great.”

So the root cause of the failures may simply be defective preproduction Nanosolar Utility Panels.

From Nanosolar 1.1 MegaWatt-peak Solar Plant

Since the Nanosolar GmbH module factory is maybe a kilometer from the PV plant, damage during shipment is less plausible outside of packing, loading, and unloading. A simple rule of thumb applies to frameless glass/glass PV modules; the bigger the glass, the higher the probability of glass damage if the modules are not handled in compliance with manufacturer specifications. Nonetheless, Nanosolar touts their 2.00 square meter modules as a technology advantage over industry leading thin film modules at 0.72 square meters because of reduced mounting materials.

The Safety and Installation Guide, Nanosolar Utility Panel, NSC-012 Rev 4 Technical Note, from April 2011 includes a page each of Safety Precautions and Mounting instructions. Among the Safety Precautions, the following are most relevant to handling:

• Multiple people may be required to carry the panel.
• Do not stand on, drop, scratch, or allow objects to fall on solar panels.
• Never pull, carry, or orient the solar panel by its cables. Handle solar panel only by the glass.
• Never leave a solar panel unsupported or unsecured; store inside shipping pallet until ready for installation. If a solar panel falls and glass is broken, the solar panel poses an electrical safety hazard and can neither be repaired nor used.
• Any solar panel with broken glass poses an electrical hazard and must be replaced immediately.

In particular, the last point does not appear to have been followed thus far at the Luckenwalde 1.1 MWp landfill plant. BELECTRIC, previously Beck Energy, completed the installation in June 2010 after about 18 months of delays in the delivery of CIGS (Copper Indium Gallium diSelenide) modules by Nanosolar.

From Nanosolar 1.1 MegaWatt-peak Solar Plant

The Mounting portion of the Nanosolar Utility Panel technical note specifies the exact position of the four (4) clamping points and:

• Use only solar panel mounting clamps tested and approved for use with Nanosolar solar panels.
• Mounting clamps must have polymeric (elastomeric) elements that completely contact the indicated panel surfaces.
• A bow (<27mm at 2400 Pa) at the panel center will not affect panel function; panels can be mounted as described below.
• For systems that may experience heavy snow loads (2400 – 5400 Pa), two rails with elastomer pads must be used on the same spacing as that used for the clamps.

Unapproved clamps or clamps screwed on too tightly could explain the damaged PV modules as well as improper installation of the two (2) back rails for snow loads. Another speculation involves mounting structure tensions caused by the sloped ground at the former landfill.

However, it’s hard to imagine BELECTRIC, the top ranked 2010 Global PV Systems Integrator by IMS Research, not following the Nanosolar Mounting guidelines. As a Nanosolar investor and project partner, BELECTRIC is almost certain to have helped Nanosolar write the technical note.

From Nanosolar 1.1 MegaWatt-peak Solar Plant

The juwi solar poster concludes:

Shipping/Packaging and Handling and Installation are the greatest mechanisms of module failure in the field for these installations.

And the last of the juwi solar lessons learned from the field:

Operation and Maintenance requires special attention to prevent externally caused damage to modules by maintenance crews and rocks kicked up during mowing.

Both Nanosolar and BELECTRIC were mum in response to my inquiries on the matter.

Overdue Nanosolar PV projects?
What ever happened to those new utility scale PV projects Nanosolar said would be installed by Spring 2011? In the EDF Energies Nouvelles 2010 Activity Report (page 37), Nanosolar CEO Geoff Tate said:

In 2011, EDF Energies Nouvelles is building a 3 MW test installation in Gabardan (France) with Nanosolar Utility Panels and another 3 MW installation in Salem, Oregon (USA).

Of course, earlier in April 2011, “News feature: Nanosolar inks deals with three European installers for up to gigawatt of CIGS panels” by Tom Cheyney at PV-Tech.org said:

Shipments of panels have already begun, according to Brian Stone, Nanosolar’s VP of worldwide sales and marketing. He said in a phone interview with PV-Tech that the company is “in construction with Energies Nouvelles on a 3MW plant in Bordeaux (Gabardan), France. Those modules were shipped in the first quarter. We have additional plants with [the three integrators] over the balance of this calendar year.”

Now “Never mind “you know who”: CIGS thin film survivors Nanosolar, Stion keep going about their business” again by Tom Cheyney at PV-Tech.org said:

Brian Stone told me at Intersolar North America in July that many pieces of production gear were coming into the company’s San Jose cellmaking fab at that point, and that it was on track to reach 100MW cell capacity in 2012. He also said there would be some new multimegawatt projects to talk about later in the year; apparently, one of those projects will be announced in the next few weeks.

So perhaps Nanosolar really has shipped sufficient modules for a few MegaWatt scale PV projects.

More funding needed
After raising almost $500 million in 2008, “Analysis: Solar startups plough ahead despite Solyndra” by Nichola Groom for Reuters said:

Nanosolar’s vice president of worldwide sales, Brian Stone, said the company will be able to get its costs below those of First Solar once it doubles its factory capacity next year. To do that, however, Nanosolar needs to raise money later this year. Stone declined to say how much the company will need to raise, but said he was not worried Solyndra’s collapse would make it more difficult to secure that funding.

A year ago, the Nanosolar Blog post, “Nanosolar Confirms Factory Expansion and Financial Strength”, said:

Nanosolar is funding its solar cell factory expansion with its existing cash reserves. The company plans to reach cash-flow positive operations in 2012 without having to raise additional equity capital.

But that’s Nanosolar, and the PV times have radically changed in 2011.