PV Modules

Technological improvements contribute to enhancing the already high attractiveness of SHJ shingle technology, and to close the gap with industrial, economic and sustainability requirements usually considered for large-scale deployment of such panels.

This paper presents a way to evaluate production windows and related field issues using an adapted failure mode and effects analysis (FMEA) approach. Since PV modules are the most important component in terms of longevity and warranties, the focus of Fraunhofer’s work has been on module manufacturing. The process, however, can also be applied to cell manufacturing and other steps in the value chain.

Low-temperature interconnection processes for high-efficiency PV cells will be a key R&D topic in the coming years. In reality, to avoid significant deterioration of the surface passivation, the metallization and interconnection processes of silicon heterojunction (SHJ) cells are limited to temperatures below 200°C; tandem cells with a perovskite subcell demand an even greater reduction in process temperature, namely below 130°C. Moreover, to ensure the sustainability of PV production on a TW scale, the use of scarce materials, especially silver, needs to be reduced, as 10% of the world’s supply was already dedicated to PV in 2020. This paper addresses the results obtained in terms of reducing the silver consumption in interconnection technology based on electrical conductive adhesive (ECA) and Pb-free ribbons.

After several years of technological developments, measurement and quality standard specifications, and bifaciality implementations in energy yield simulation programs, bifacial PV has become reliable and will shortly become accepted as a valuable commodity. Since 2020, bifacial passivated emitter and rear cell (PERC) technology has been king of the energy markets, and, in combination with simple tracking systems (e.g. horizontal single-axis tracking – HSAT), the lowest electricity costs have been achieved. Because PERC is reaching its limit in terms of efficiency, and n-type technology is gaining momentum, in the future n-type PV (nPV) will replace PERC technology as the workhorse of the PV electricity market. This paper describes why, and most likely when, this will happen and which n-type technologies will be leading the pack in the race to bring electricity costs well below €0.01/kWh.

With mature product offerings now available from several of the leading industrial PV equipment and tool manufacturers, and latest-generation ECAs available from suppliers, this article aims to provide important background information on ECAs, as well as give a brief overview of some of the challenges and cutting-edge developments in ECA-related PV applications.

Because it leads to higher efficiencies than aluminium back-surface field (Al-BSF) cells, passivated emitter and rear cell (PERC) technology is attracting more and more attention in the industry and gaining market share. However, PERC technology brings new challenges with regard to the phenomenon of degradation: some monofacial/bifacial PERC cell modules were found to demonstrate much higher power degradation than Al-BSF cell modules after damp-heat (DH: 85°C and 85% relative humidity RH, 1000h) and potential-induced degradation (PID: 85°C and 85% RH, –1,500V, 96h) tests, which will be the focus of this paper.

The realistic measurement of solar cells is key for the whole PV industry, as accurate information about cell power is one of the most important aspects in solar cell purchase and PV module design.

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.

Half-cell modules are gaining an increasing market share because of their potential for increasing module power without requiring any changes to cell technology. However, it has emerged that different cell separation technologies can produce similar electrical performances of the half cells, yet lead to an entirely different mechanical behaviour of the cells.

The market share of bifacial solar modules is rising, because of the additional power yields of up to 20% per year, which reduce the levelized cost of electricity (LCOE). Many manufacturers have bifacial PV modules in their portfolios, with a majority of them employing bifacial passivated emitter and rear cell (PERC+) technology. In this paper, it is shown from the results of studies that rear-side-related potential-induced degradation (PID) effects can occur in addition to the conventional front-side shunting type (PID-s).