Plant Performance

Despite the importance of reliability to the cost competitiveness of PV, large data sets enabling high-level investigation of the technology’s performance in the field are relatively scarce. Dirk C. Jordan, Chris Deline, Bill Marion and Teresa Barnes of the National Renewable Energy Laboratory, and Mark Bolinger of the Lawrence Berkeley National Laboratory study a unique data set of 100,000 PV systems in the US, drawing out tips for better reliability that have relevance to other parts of the world.

Many of the bifacial modules now offered by PV manufacturers employ bifacial passivated emitter and rear cell (PERC+) technology, making them vulnerable to rear-side potential-induced degradation, in addition to the conventional front-side shunting type (PID-s). Kai Sporleder, Volker Naumann, Stephan Großer, Marko Turek and Christian Hagendorf of the Fraunhofer Centre for Silicon Photovoltaics report on new testing methods designed to quantify the expected power PID-related losses in bifacial PERC+ modules in the field.

Understanding of LeTID remains incomplete, although its effects on PV power plant performance are recognised as being potentially significant. Tabea Luka, Friederike Kersten, Matthias Pander, Max Koentopp, Marko Turek, Werner Bergholz and Thomas Pernau of the LeTID Norm consortium outline progress towards developing a standardised test for the defect, a key step in minimising its impact.

The use of unmanned aerial vehicles in solar operations and maintenance can reduce costs and save hours of painstaking labour, but only if applied correctly. Aline Kirsten Vidal de Oliveira, Mohammadreza Aghaei and Ricardo Rüther explore the optimal use of aerial inspections and emerging methods for analysing the data they gather to identify faults.

Potential-induced degradation (PID) is still one of the main reasons for unpredictable power losses in PV power plants. Volker Naumann, Otwin Breitenstein, Klemens Ilse, Matthias Pander, Kai Sporleder and Christian Hagendorf of Fraunhofer CSP examine how the PID susceptibility of PV modules is influenced by environmental stress. It is found that PID may develop in originally PID-resistant modules after a period of one to three years of unsuspicious operation, depending on climatic conditions.

The services and skills offered by asset managers have a central role to play in boosting the value of solar PV investments. Adele Ara, Máté Heisz, Magda Martins, Diego Molina and Paul Norrish outline the key recommendations in the solar industry’s first set of best practice guidelines for asset managers.

Testing a sample of modules at an operational solar can help identify faults and underperformance in the wider plant, but which ones to choose? Authors from Mahindra Teqo describe a new methodology they have developed to Satish Pandey, Preetha Pillai, Sandeep Jadhav, Shyam Kumar, Gaurav Mishra, Rajesh Kumar Dhuriya.

New technologies are helping revolutionise the management and profitability of PV power plants. Martina Pianta, Guillermo Oviedo Hernández, Constantinos Peonides, Will Hitchcock and Máté Heisz look at some of the digital innovations helping advance the deployment solar energy in Europe and beyond.

Different types of PV backsheet provide modules with varying levels of protection in warm, humid conditions. Haidan Gong, Minge Gao and Yiwei of Wuxi Suntech’s PV test centre detail the results of research undertaken to better understand the properties of different backsheet materials in tropical conditions.

Floating solar has caught the industry’s imagination in recent years, opening up potentially limitless new opportunities for PV installations in land-constrained parts of the world. Ben Willis reports on the work underway to address questions about the performance and reliability of water-based solar installations.