Aerial inspection of solar plants goes mainstream

Using drone and manned aircraft for fast and accurate inspection of solar assets.


Solar asset owners such as SMA are finding that aerial inspections using drones and manned aircraft are the optimal way of managing and maintaining large solar installations. SMA,

SMA has O&M contracts for over 1,000 sites, from small commercial of 30 kW and up to large-scale installations of over 600 MW. The company has been managing assets since 2015 and since then much has changed in terms of the technology and techniques used.

Thermal mapping reveals defects in PV panels that can’t be seen with the naked eye or standard photographs, helping assess performance and schedule maintenance.

Today they are using drones and manned aircraft to conduct thermal and visual inspections of modules, looking for defects or modules or strings or groups that may be offline. In the course of inspection, they may see, for example, strings, modules and sections offline because an inverters not running, but the majority of the time the imaging is finding broken modules or hot spots on modules.

pv magazine spoke with Mark Culpepper, general manager solar solutions with DroneBase, a global company that specializes in data captured through aerial imaging. DroneBase serves a range of industries including wind energy, insurance, construction, real estate, and more—but the solar industry has increasing become a focus as solar assets increase across the globe.

Aerial inspections have great benefits in the solar industry not the least of which is speed. An unmanned drone can inspect about 20 MW per day per drone operator for on-demand thermal inspections or spot checks, while manned aircraft can capture over 500 MW in a 4-hour period. SMA uses both unmanned drones and airplanes to complete its inspections, finding aerial imaging far superior to “the old way” of doing things, which was manual inspection.

What’s the difference between the two? “It comes down to picking the right tool for the job,” says Culpepper. “Drones are the best tool for spot checks of solar energy systems. We use manned aircraft for two reasons: for annual health scans of systems and to capture images of large projects and portfolios.”

DroneBase recently announced its North American Solar Scan program, which flies each spring and fall and cover every major solar market in both Canada, including Ontario, and the United States, including California, Nevada, Colorado, Texas, Florida, North Carolina, South Carolina, Illinois, Massachusetts, and more.

Manual inspection required an inspector to go into the field and, using an I-V curve tracer, the inspector would go inside each combiner box, check every string while it’s operating, check every string after they pull the fuse out and see where it’s sitting, etc. Jamie Mordarski, Director, O&M Americas at SMA America, told pv magazine USA that the problem with manual inspection is time.

“It takes anywhere between 15 to 25 minutes per combiner box and if you have a site that has a combiner box with say 1200 combiners boxes, that’s 400 man hours.” He added that in addition to the time it takes, manual inspection doesn’t tell you what the problem is or what module it is. The inspector would have to isolate the string to figure out which module it is.  With a thermal aerial scan, a 600 MW site can be done in 5 hours.

Mordarski said that seven years ago when SMA started using aerial imaging it was not something that every solar asset owner was doing. When he saw what aerial imaging companies like DroneBase could do and how beneficial it was, he knew it was better than going out into the field with a meter. “As people are starting to see more aerial inspection, they realize it’s better, cheaper, quicker, easier,” said Mordarski. “Doing it the old way just doesn’t make sense.”

To conduct its inspection, SMA uses a combination of drones and manned aircraft. Many of the inspections they can do with their own pilots and drones/airplanes, and for very large or highly concentrated portfolios they hire DroneBase. Even when SMA does its own inspections, it supplies SMA’s raw data to DroneBase to complete the analysis.

Technological advancements

Dramatic changes have occured in the technology in the seven years that SMA has been conducting aerial thermal imaging inspections. Mordarski said that there were not off-the-shelf drones back then, and the inspection companies that SMA was working were getting custom built drones from Europe and adding off-the-shelf thermal images that weren’t really made for drones. Some were even using GoPro cameras that they’d strap to the drone. Now drones are made with high-resolution thermal imagers on them natively so you don’t need two separate cameras. They are also capable of doing automated patterns, where you draw a box on a map, set your parameters and off you go. “It does it by itself,” said Mordarski.

Inspections of solar assets by manned aircraft is also becoming more common. It used to be that the drones got better resolution because they fly closer to the solar installations than planes, which have to fly higher. Mordarski pointed out that today you can get the same resolution from the plane as from the drone as long as you’re flying at the right altitude. “The technology has improved, speed has improved, quality has improved, and the cost per engagement has gone down.”

From niche to mainstream

In just a few years, aerial inspection of solar assets has gone from a niche application to mainstream use. Technology has advanced dramatically in the intervening years, and cameras and imaging continues to advance, along with new ways of analyzing the data. For example, DroneBase recently acquired India-based AirProbe, a specialist in drones using artificial intelligence in its analytics. As a result of these new capabilities, DroneBase is expanding its offering to include construction progress monitoring, serial ID mapping, and advanced shade analysis. Overall, aerial inspection has gotten to the point where “everyone has to do it,” said Mordarski. The bottom line, according to Mordarski is that using aerial thermography and high-resolution visual inspection is somewhere between 10x lower cost and 30x as fast as doing it by manually. For SMA, there’s no going back.

Foliage Shading Effects PV Systems.

PV systems, as we all know, rely on the sun and panels that are shaded produce substantially less than their unshaded counterparts, which costs you money in the end. If you notice your panels being shaded, it is definitely something you want to address quickly. A simple trimming can save money on your electric bill, so we always recommend having any trees near the panels trimmed back.

pacific panel cleaners

US Solar Plants Now Expected to Run for More Than 30 Years: Berkeley Lab.

While solar technology has been rapidly advancing, prices have also been dropping. According to Green Tech Media in their recent article, the average lifespan of a solar project has increased from 21.5 years in 2007 to 32.5 years as of now. What’s even better is that operating costs have been halved since then as well! This is great news for anyone looking to invest in solar projects because when the lifetime of your system is increased and operating costs are reduced, more money is saved in the long run. With this news, we hope to see more solar projects in Hawai’i and the rest of the U.S., because saving money and moving towards green technology is beneficial for everyone. For more information, check out the article linked below.

social distancing grace of progress

PPC: New Guidelines for Service.

We at PPC are working hard to protect your solar investment and keep your energy at peak status.

Being a premier photovoltaic maintenance company, we are aware of the current unique situation now having to deal with a national, and global, pandemic crisis. The Pacific Panel Cleaners team is ready to serve your solar panel needs under these special circumstances.

PPC management will be sending out postcards with this and additional information to help our customers at this time. Please contact us at anytime for details or questions

We are keeping in accordance with the Governor’s Law of social distancing and we are not knocking on doors talking to our clients at this time so we will text or call upon arrival.

We will also let you know when we are leaving. 

We apologize about this as we do enjoy talking story face to face with our clients. This does not mean we cant talk story but have to do it on the phone or from greater than 6 feet away-These times will pass and we know that but for now we have to follow the Laws being passed during these times for all our safety.

Thank you kindly 

Be Kind

Stay Safe

Fred and your team at Pacific Panel Cleaners LLC

Panasonic is leaving Tesla’s solar panel “gigafactory” in Buffalo

By Kelly Pickerel | February 26, 2020

When SolarCity purchased module manufacturer Silevo in 2014, the company immediately took over plans for a 1-GW manufacturing plant in Buffalo, New York, with the goal to begin production of SolarCity-branded panels by 2017. Then Tesla bought SolarCity in 2016, and Tesla inked a deal with Panasonic to jointly use the Buffalo plant to produce PV cells and modules. The two companies have a long collaborative relationship, especially in EV and battery cells.

But now it’s been announced that Panasonic is leaving the Buffalo plant, putting many supposed solar products in jeopardy. Panasonic was the only company on record producing solar cells in the United States, and many assumed Panasonic solar cells were being used in Tesla’s Solarglass solar roof product. (PV Magazine has done some excellent work trying to determine where Tesla’s products are being manufactured.)

Panasonic will cease U.S. solar manufacturing operations in May and should completely exit the Buffalo facility by the end of September 2020.

Howard Zemsky, Empire State Development Chair, confirmed Panasonic’s departure in a statement yesterday. Zemsky said that Tesla has informed the organization that it has “not only met, but exceeded their hiring commitment in Buffalo.” Tesla said it has more than 1,500 jobs in Buffalo, not counting Panasonic employees at the plant. If confirmed to be true, Tesla will avoid paying a $41.2 million penalty to the State of New York, which required Tesla to hire 1,460 people to receive certain incentives.

“This count does not include the Panasonic positions and — while their operations were co-located at RiverBend — there was no incentive package between the state and Panasonic. We understand that Panasonic has made a corporate decision to move away from global solar products, but this action has no bearing on Tesla’s current operations nor its commitment to Buffalo and New York State, according to Tesla,” Zemsky said.

Zemsky also said that Tesla has indicated it intends to hire as many Panasonic employees impacted by Panasonic’s departure as it can.

As part of the Tesla-Panasonic Buffalo collaboration agreement signed in 2016, Panasonic agreed to cover required capital costs at the plant. Panasonic had been manufacturing its high-efficiency solar cells and selling them to other module assembly companies. Now the company is streamlining its global solar operations by integrating solar into its “energy solutions business,” which also includes energy management systems, batteries and EV chargers. Panasonic will continue to sell Panasonic-branded panels to U.S. customers through its own distribution network.

“We are proud of what Panasonic has accomplished as a pioneer in the solar space and the significant role Panasonic employees in Buffalo have played in that success,” said Shinichiro Nakajima, director of Panasonic’s Energy System Strategic Business. “The decision to transition away from U.S. solar manufacturing in Buffalo aligns with our global solar strategy, our efforts to optimize development and production, and supports Tesla’s long-term plans to continue and expand its operations.”

With no domestic solar cell production, U.S. module makers are still dependent on foreign, tariffed solar cells for its end-products. Shuttered Suniva has indicated plans it wants to restart cell manufacturing in Georgia, but nothing has been confirmed. Solar cell equipment manufacturer Meyer Burger announced last year that an unnamed solar cell manufacturing startup had signed a contract to install new equipment somewhere in North America. Nothing yet has been confirmed with that contract.

2019 AEE World Energy Conference

2019 AEE World Energy Conference

Identifying Issues on Installed Photovoltaic Systems. By Fred Brooks.

Evolution of PV System Maintenance 

• With all things there is an evolutionary processIn 2009 I started operating the first company in Hawaii solely dedicated to Photovoltaic System maintenance. After a few years I knew there was more to the inspections than meets the eye, and that is when I first became a certified thermographer. That was in 2012. This was the natural next evolutionary step

General Conditions for an Inspection

  • The Photovoltaic system needs to be up and operating
  • We need a basic understanding of the PV system. Is it a central inverter, micro inverter or an optimizer system?
  • We want to ideally have clear skies
  • We are looking to have an irradiance greater than 500 w/m2
  • You can see anomalies at any level but 500 w/m2 and greater is where you can really see the anomalies pop
  • The main concept is to realize you are looking for anomalies on the system in relationship to the rest of the system, as the equipment should have a uniform heat signature in relationship to each other.



AEE World Energy Conference 2019

The #founder & #CEO of our company, Pacific Panel Cleaners, Fred Brooks, CEM, CEA will be speaking at the #aee #worldenergy #conference in #WashingtonDC this year! If you’re there, don’t miss his #presentation on #thermalimagery on Thursday, September 26th from 2:30-3:00pm. Such an #honor to be invited & be a part of this #energy #expo!
#pv #pvindustry #solar #greenenergy #thermalimaging #photovoltaic