Silicon heterojunction (SHJ) solar cells demonstrate a high conversion efficiency, reaching up to 25.1% using a simple and lean process flow for both-sides-contacted devices, and achieving a record silicon solar cell efficiency of 26.7% in back-contacted configuration. In addition, the field advantages of SHJ cell technology are a native bifaciality and low thermal coefficient providing impressive energy yield. Finally, the technology demonstrates potential cost reduction as it is perfectly suited for thin wafers integration. The SHJ technology is therefore today triggering strong interest in the PV industry, appearing on the roadmap of different cell manufacturers, with several production lines and pilot lines being installed worldwide. One limiting factor of the technology is related to the metallization: due to temperature restrictions on heterocontacts, the standard firing through silver paste needs to be replaced by low curing temperature paste. This type of pastes yield fingers with higher bulk resistivity (two to three times the one obtained with high temperature cured silver pastes) and lower adhesion after soldering. In this paper, materials, processes and costs figures will be reviewed for the metallization and module integration of SHJ solar cells, with a focus on copper plating benchmarked to silver screen-printing, for varying module interconnection technologies.
Improving PERC cells requires rather different strategies than standard cells have required, demanding concrete improvements in materials, manufacturing procedures and fabrication tools.
Improving the texturing approach for diamond wire-sawn (DWS) multicrystalline silicon (mc-Si) wafers is one of the key steps to decrease its efficiency gap with monocrystalline silicon-based solar cells. In this regard, black silicon texturing has increasingly caught attention of both academia and industries as a potential approach towards mass production of high-efficiency mc-Si solar cells. In this paper, the challenges of implementing such a texture, with unique feature sizes, in mass production are discussed in detail, and the latest results are reviewed. Finally, results of the first trials at high volume manufacturer applying an alternative plasma-less dry-chemical etching (ADE) method are presented.
PV manufacturing capacity expansion announcements in the second quarter of 2018 were slightly higher than the previous quarter, although activity slumped specifically in June, following China’s decision to suddenly cap utility-scale and distributed generation projects. The quarter was also characterized by activity in India, partially driven by a major Chinese manufacturer. The report will also analyze first half year capacity expansion plans and targeted locations, globally.
After defining the term Industry 4.0 according to the authors’ interpretation, this paper elaborates on the opportunities and challenges that the Industry 4.0 transition will bring to the PV sector. The topic is approached from various angles. How can the PV industry and the related value chain itself progress to Industry 4.0? And how does this reflect in different application sectors, such as construction and automotive? This paper presents a future scenario towards which the industry could be heading; some of the steps already being taken and some of the main challenges ahead are described. The value of PV technology as an enabler for other sectors, such as edge versus cloud computing, to move into Industry 4.0 is also touched upon. Additionally, a number of enablers and boundary conditions are highlighted in the context of Industry 4.0 and their relevance to the PV industry (legislation, cyber security, etc.) The status of Industry 4.0 in PV compared with other sectors is also explored. Wherever appropriate and possible, examples of projects and activities that illustrate the described topics are given.
An analysis of R&D spending of 20 publicly listed PV module manufacturers in 2017 has been undertaken to replace Photovoltaics International’s previous list of 12 companies tracked over a 10-year period.
A number of the original companies tracked have subsequently de-listed from stock markets and gone private, which meant that a broader analysis, including other listed companies was required to provide a good representation of global R&D spending trends in the PV wafer, cell and module segments of the upstream solar market.
Welcome to Photovoltaics International 41. An emerging theme in the industry further downstream is the growing variety of bankable PV modules. It’s a topic we’ll be picking up on 23-24 October at our PV ModuleTech conference in Penang, Malaysia.
This issue of PVI captures the ongoing work to drive improvements across the full range of those technologies. From the exploration of next generation CIGs cells to the commercial improvements of PERC by Trina Solar, this edition neatly captures that variety.
Fraunhofer ISE reviews the latest results from efforts to improve the texturing of diamond wire sawn wafers.
Trina Solar presents a roadmap for PERC improvements that it claims could halve costs while pushing efficiencies to 24% in around seven years.
ECN and imec explore the latest developments in integrated cell to module manufacturing approaches from the more familiar multi-busbar and multi-wire to shingling and woven fabric and foil-based module technologies for back contacted cells.
Elsewhere, CSEM INES zooms in on a major limiting factor for silicon heterojunction cells, metallization.
All the regular features including our news reviews and R&D spending report make a return, plus lots more.
Following on from this bumper edition, PVI42 will be published in Spring 2019.
Smoothing and firming are often discussed to make renewables appear more like conventional generation to the grid operator, but how smooth and how firm does that generation need to be? How can the attributes and operations of energy storage be appropriately measured relative to cost? Andres Cortes and Ben Kaun of the Electric Power Research Institute discuss recent work addressing these issues
Trade tariffs, technology changes, new suppliers and shifting timelines. US developers and EPCs are riding out challenging times. John Parnell looks at the scale of the upheaval and how module pricing and module technology changes are feeding into the day-to-day work of deploying megawatts
With so many options open to them, EPCs and developers are faced with confusing choices to make over the right PV module technologies. Finlay Colville and Mark Osborne explore the importance of stringent third-party testing in avoiding asset underperformance
