Innovators around the globe are proving solar photovoltaic (PV) plant performance can be enhanced by retrofit technologies. Which aspect of the system, expectations of performance boosts and regulatory and Fit market variables represent just a few of the parameters to navigate to create the right match of technologies to plant attributes.
Retrofit solar technology considerations encompass a number of factors including a plant’s current performance levels against expectations, market drivers for energy returns, regional geographic factors and original equipment considerations.
To get an insider’s view of increasing solar plant performance with retrofit technologies, Solar O&M Insider recently spoke with Paul C. Ahrens, President and CEO of CSD Nano and Maurizio Manenti, Manager, New Technologies of Alectris. For the full discussion listen to the podcast or reference the transcript here.
Underperforming versus FiT Market Solar Plants
Determining the right strategy for retrofit solar enhancements is a necessary first step. Understanding the market drivers influencing the profitability of the PV plant is key. Is the plant you are considering for such work underperforming or does the output represent an opportunity to realize higher Feed in Tariff (Fit) market profits?
“It’s important to differentiate retrofit technologies,” explained Paul Ahrens whose company, CSD Nano, develops anti-reflective thin films applicable to a number of industries including solar photovoltaic plants. CSD has created MoreSun® a solar coating that can be applied in the field to operational solar panels.
“You can come up with a technology that will specifically address what is causing the underperformance, in which you can essentially bring it back up to its original performance. An example would be addressing PID, Photovoltaic Reduced Degradation. On the other hand, you can ensure the plant is working absolutely perfectly, exactly as it was designed, but yet it didn’t have an anti-reflection coating that came from the glass factory. With an anti-reflection coating, you can actually improve the performance beyond what it was originally designed,” explained Aherns.
This over and above the original performance specifications approach can add energy output in FiT markets. Older solar markets including Germany and Italy where FiT programs exist benefit investor’s efforts for increased performance.
In Italy, owner/operators have important incentives for new technologies, explains Alectris’ Maurizio Manenti. “Iper-Ammortamento is a facilitation of taxation provided by the ‘Budget law 2017’ in Italy. It is an incentive making it possible to amortize the investment for a value equal to 250% of the investment itself.”
On a global scale the impact of retrofit technologies to generate more power from existing plants is very promising. “If we as an industry can recover 5%, 7% of efficiency,” says Manenti, “we can create a huge number of gigawatts of power and green energy from existing plants, which creates a real interesting future for retrofit technologies.”
Testing Plant Performance
Once you have determined plant or market factors as the key drivers for retrofit technologies, solar owner / operators need to be sure they have accurate data. Asset management and plant monitoring data are critical to knowing the status of plant performance and whether a technology retrofit is warranted.
Ahrens said, “From our perspective, what really, really counts is having a really good asset management and monitoring system. We can say, ‘Look, we can improve the performance by 3%,’ and a customer will say, ‘Well, that sounds great.’ Then we go in and take a look at the plant, and they wouldn’t know a 3% improvement if it happened the next day, because they don’t have a really good, decent monitoring system, and they don’t have really good operations in maintenance who can track and are on top of what the performance is.”
“This is why we work with people like Alectris because we know that they can actually tell if there is an improvement. You’d be surprised just how noisy the data is coming from solar plants, and there are people that really don’t know. They have kind of a gut feeling if, ‘Okay, I think it’s doing better now than it did before or last year,’ but they just don’t have the monitoring data to be able to actually measure it.”
Alectris, a solar operations, maintenance and asset management provider, dove into technologies when it became apparent existing plants needed help or were located in areas where FiT programs incentivized retrofit applications. The Alectris program includes comprehensive vetting of potential solutions and testing in the field before any widespread market push is activated.
Before any retrofit installations are recommended, Alectris conducts a series of “missions” or tests in the field to determine exact causes of underperformance. Backed up by the extensive data from the ACTIS Solar ERP program, the company’s proprietary software application, testing can surface problems with retrofit potential and then validate the improvement in performance.
Regional Factors Impacting Solar Plant Performance
In the case of the MoreSun® technology, solar plant gains can be realized by the anti-reflective and anti-soiling aspects of the coating which is influenced by regional factors.
“Anti-reflective coating, specifically ours, actually performs better creating higher gains in the evening when the sun is coming in at an angle. That also translates on cloudy days when there’s diffused light,” explains Ahrens. “There’s lots of light coming in at the array from multiple angles. This is how we get greater than a very higher performance in places where it’s cloudy or if the atmosphere is such that it diffuses light. An example would be the Calabrian plant which is very close to the Mediterranean Sea. The spectral quality of the air is not like Phoenix, where you have dry, direct sun all the time. MoreSun® actually performs better in places with a cloudy atmosphere like Hamburg than Phoenix because of the way the physics works.”
In dusty regions of the world where soiling issues degrade solar performance, the MoreSun® technology is able to provide anti-soiling protections to the arrays. Such areas include the Middle East, India, Chile, Southwest U.S., all regions where soiling is a huge problem.
“Dust just doesn’t stick to our coating,” explains Ahrens. “This benefit cuts down on the number of solar module washings needed to guarantee energy performance. The soiling is going to be less with MoreSun® and you’re going to get some better performance. We’re working with NREL here in the U.S. to help to quantify the anti-soiling properties.”
+4% Energy Increase Achieved with MoreSun® on Italian Solar PV Plants
“We started testing MoreSun® in May 2015. Our testing is verified up to a 4% more power. These recent figures beat our original estimates of a 3% performance boost from MoreSun®,” said Manenti.
“We have a plant in the south of Italy of eight megawatts we are coating. We have completed the first 2 megawatts, and the results, after 8 to 10 months, are really good. And so we are satisfied with the work we are doing together in Italy.”
In fact as seen in Fig.1 below, recent results of the MoreSun® application as shown in the ACTIS portal, have achieved a +5,42% overperformance over a 4-month observation period.
Alectris and CSD Nano are working together in several regions of the solar market. Alectris is able to verify and test MoreSun® results by tackling plants that meet specific criteria and are under monitoring and management of its ACTIS Solar ERP system.
Currently the companies are working in Italy, Greece, Germany, Japan, India, the Middle East and the United Kingdom.