PV manufacturing capacity expansion announcements in the first quarter of 2018 continued to mirror those of the previous two years, highlighting the recent trend of the last quarter and the first quarter of each year (since the end of 2015) being the most active. The quarter being discussed also represents a revival in thin-film expansion plans, the return of PV module assembly outpacing solar cell announcements and the return of India and the US as major destinations for new capacity plans.
As the PV industry strives to reach terawatt scale, addressing the last remaining cost centres of the crystalline silicon value chain will play a critical role in ensuring that the industry can continue to achieve lower systems costs, and provide the extremely low levelized cost of electricity (LCOE) required to drive the adoption of this form of energy. Wafer manufacturing remains the single largest cost driver in industrial cell production. While incremental improvements, such as diamond wire (DW) sawing, have helped to lower silicon consumption, wafer manufacturing has lacked the significant step change necessary for achieving dramatic cost reduction.
State-of-the-art black-silicon texturing technology has been successfully implemented in all of the 4.5GW multi-Si cell production lines at Canadian Solar (CSI). With a combination of black-silicon texturing and diamondwire-sawn wafers, it has been possible to increase cell efficiency and wattage, while significantly reducing the cost. To further improve CSI’s multi-Si product performance and cost, multi-Si passivated emitter rear contact (multi-PERC) technology has been developed to achieve a mass production cell efficiency of more than 20% on average, and a module power exceeding 300W. By the end of 2017, a production capacity of over 1GW had been established, and CSI’s majority multi-Si cell capacity will be upgraded to PERC in 2018. This paper will introduce the solutions to realizing light-induced degradation (LID)-controlled multi-PERC cells and modules, as well as offering a discussion of the degradation performance. In addition, the technology evolution of CSI’s high-efficiency multi-Si products and a roadmap for 22%-efficiency multi-Si cells are presented.
The extra energy gain offered by bifacial PV modules has helped make them an increasingly popular choice in the global PV industry. But the question of how to define, measure and rate the electrical output from bifacial modules is a hotly debated topic, given the extent to which the rear-side contribution is dependent on a range of variable factors relating to local environmental conditions and system configurations. Drawing on in-house modelling and simulation software developed at TÜV Rheinland, this paper explores the power rating issue for bifacial devices, examining the definitions of rear irradiance, measurement test method, power stabilization and verification for type approval. Relevant reliability and safety tests are discussed, with additional modifications and suggestions for bifacial PV modules.
Crystalline silicon heterojunction (HJT) solar cells and modules based on amorphous silicon on monocrystalline wafers offer advantages over established wafer-based technologies in terms of efficiency potential, complexity of the manufacturing process, and energy yield of the modules. The temperature sensitivity of these solar cells, however, poses considerable challenges for their integration in modules. Currently, there exist three approaches for the interconnection of HJT solar cells, each with its own strengths and weaknesses: 1) ribbon soldering with low-meltingpoint alloys; 2) gluing of ribbons by using electrically conductive adhesives (ECAs); 3) SmartWire Connection Technology (SWCT).
TOPCon is regarded as a possible follow-up technology to the passivated emitter and rear cell (PERC) concept. This paper presents the latest results for high-efficiency solar cells, and the progress made on migrating layer deposition to high-throughput tools, which are already in use in industry. Possible metallization approaches, and three different industrially relevant solar cell structures featuring TOPCon, are also discussed.
Welcome to the tenth anniversary edition of Photovoltaics International. Over the past decade this journal has documented the latest developments in the fast-changing of world PV technology, bringing you exclusive insights from researchers working at the industry’s cutting edge.
Over that time the pace of change has been astonishing, so much so that it scarcely seems as though one new technology is accepted before the next arrives on the scene. So seems to be the case with the passivated emitter and rear cell (PERC), which having become the technology upgrade of choice across the industry now appears to have a successor in waiting.
In this edition researchers at Fraunhofer ISE look at so-called tunnel oxide passivated contact (TOPCon) technology as a follow-up to PERC. Meanwhile, a team from TÜV Rheinland takes a deep dive into the vexed question of how the industry can most usefully define the benefits of bifacial technology. At the other end of the value chain, US-based 1366 Technologies gives an account of its contribution to reducing costs in wafer manufacturing, a significant ongoing expense in industrial PV cell production and thus a key focus for efforts to drive down the levelized cost of solar-generated electricity.
Elsewhere in this edition, Canadian Solar outlines some of the solutions it has developed for tackling light-induced degradation in multi-PERC cells and modules, a persistent challenge with PERC technology. In this edition our deputy editor Tom Kenning reports from the recent PV CellTech event in Malaysia, where the ‘Who’s Who’ of the PV manufacturing world gathered to debate the current state of play in solar technology.
Welcome to the latest edition of PV Tech Power. Installed solar power capacity already rivals nuclear power and could well surpass it by the end of 2018. Rapid improvements in solar cell technology, module configuration, system design and financial innovation have been a big driver. Increasingly, we are seeing this mammoth legacy fleet continue to benefit from technical improvements ranging from intelligent monitoring to using machine learning and energy storage to predict when charging a battery offers a better return than feeding the grid. We’ll explore a range of activities covering hardware and software, from module to market, that are helping asset owners maximise the value of solar.
PV Tech Power’s annual Africa-focused special report is an opportunity to gauge the fortunes of solar and other renewables in a region where they arguably offer the most. Last year we charted some of the sector’s key milestones and argued that it looked as though the pace of progress was set to gather pace. A year on, that certainly seems to have been the case.
Leading PV inverter manufacturer Huawei discusses recent technical developments to a better understanding of bifacial solar module PV power plants, using three recent case studies. These efficient PV modules need to be used with devices such as inverters to maximize value. Recently, many inverters and solutions that match bifacial modules have appeared in the industry. Which solution is the best match for bifacial modules? Based on a large amount of experimental data, this article describes the solution needed for bifacial modules.
