PV industry module and component manufacturers have brought down costs significantly over the last four years. This trend is clearly evident as most publicly traded companies continue to grow revenue despite falling module and component prices. However, it is far less clear how downstream system integrators are handling the drop in system prices and contributing to value creation. System prices are generally higher in the U.S. than in Europe, despite lower module prices in the U.S. This disparity often raises questions on the part of European PV professionals where these costs come from, and secondly, what have U.S. system integrators done to reduce costs. This two-part series will shed light on how U.S. system integrators have undertaken tremendous efforts to decrease cost and add value through innovation by focussing on labour-intensive value creation in the downstream segment. Part I will focus on the residential market segment by delving into activity cost savings through innovation in engineering and construction, while Part II will illustrate how changes in sales, rebates, interconnection, and the supply-chain management over the last five years have reduced costs.
“Handle with care” – this world-renowned warning sign is inherently printed on every wafer until it is safely wrapped into a finished module – and for good reason. Despite the declining price of silicon and the improved manufacturing methods, the raw wafer still has a major share in the overall cost of a module. If we assume an average wafer price of €2.70 for a 156mm multicrystalline wafer, the finished cell will cost about €4.00. Adding in the module manufacturing costs, a cell in a typical module will cost €5.00. Hence, the wafer accounts for more than 50% of the total manufacturing costs, and as such is key to optimizing the costs in the solar value chain for crystalline photovoltaic products. This paper offers some guidelines on the wet wafer separation process that are intended to aid in minimizing the cost associated with wafer breakage.
Canada is aggressively pursuing solar photovoltaic manufacturing. Ontario, the province leading the charge, is already the manufacturing hub for other products in Canada and currently boasts one of the most generous feed-in tariffs in the world. This incentive is closely tied to domestic content restrictions in order to foster Canadian photovoltaic manufacturing. In addition, a host of other tax incentives and research and development stimulus packages are making Canada an increasingly popular destination for both established manufacturers and start-up companies.
Advanced Process Control (APC) has become an indispensable cornerstone of today’s semiconductor manufacturing. With roots in chemical processing, APC has not only proven itself in semiconductor manufacturing, but has potential to enhance yield in adjacent industries, such as photovoltaics. This paper gives a short introduction to APC, including its key elements, and proceeds to illustrate examples and success stories from the application of APC in semiconductor manufacturing. Based on these application examples, the lessons learned are summarized and the potentials of APC for PV are derived.
Encapsulant materials used in PV modules serve multiple purposes. They physically hold components in place, provide electrical insulation, optically couple superstrate materials (e.g., glass) to PV cells, protect components from mechanical stress by mechanically de-coupling components via strain relief, and protect materials from corrosion. To do this, encapsulants must adhere well to all surfaces, remain compliant, and transmit light after exposure to temperature, humidity, and UV radiation histories. Encapsulant materials by themselves do not completely prevent water vapour ingress [1-3], but if they are well adhered, they will prevent the accumulation of liquid water providing protection against corrosion as well as electrical shock. Here, a brief review of some of the polymeric materials under consideration for PV applications is provided, with an explanation of some of their advantages and disadvantages.
This paper presents fluorescence detection as a new tool for the investigation of the degradation of EVA. The superior sensitivity of the setup contained herein allows an early assessment of the changes of the EVA after only 20 hours of damp-heat exposure. A newly developed scanning system allows the spatially resolved inspection of entire PV modules. Degradation of the encapsulants was detected after two years’ outdoor exposure, as was the effect of cracks in c-Si cells, which coincide well with cracks made visible by electroluminescence.
Despite the collapsed Spanish market and the general state of the world’s economy, the past year was not a bad year at all from the perspective of installed power capacity of large-scale PV power plants. Installed power capacity surpassed expectations while also bringing new markets into the spotlight, which means that the traditional market leaders of Spain, Germany and the U.S. are no longer the only ‘key’ markets. With the exception of Germany, the past year’s most noteworthy market boost was seen in the Czech Republic and Italy, with similar shake-ups seen in the Asian tiger countries of China and India. With many large-scale PV power plants recently brought into commission in these countries, China and India are brimming with potential for the near future.
This paper gives an overview of the French PHOTOSIL project that deals with the purification of metallurgical-grade (MG) silicon via different stages of upgraded metallurgical-grade (UMG) silicon to finally arrive at a purity level that is compatible with the requirements of the silicon-based PV industry. However, purified UMG silicon in general and by definition does not reach the ultra-high purity levels of electronic-grade (EG) silicon. Based on the PHOTOSIL project, this paper presents the typical technical challenges and problems encountered with less pure purified UMG silicon and how they were resolved, both during silicon purification and crystallization and the processing of solar cells.
The ninth edition of Photovoltaics International was published in August 2010. It features Fraunhofer IISB looking at advanced process control techniques in Cell Processing, NREL gives an atmospheric thin-film deposition technique overview, and in Power Generation REC looks at reducing BOS costs with new technology and economies of scale.
Solar cells are generally built in a process facility, often a turnkey line, where high throughput, minimum handling, and lowest cost are dominant factors. There are many complementary metal oxide semiconductor (CMOS) lines in the semiconductor industry – probably more than the number of turnkey lines – where yield, reliability, and device size and complexity are major issues, where millions of chips are made with very close tolerance, and the cost of importance is that of the finished chip. The possibility of using or converting a CMOS line for building Si solar cells has been considered by many in the past [2]. These lines have advantages such as sophisticated and highly developed automated equipment, frequent in-process metrology and quality control, and a high degree of flexibility as well as highly advanced shop floor control systems. The major disadvantages are cost and low throughput. This paper will discuss the differences, advantages, and disadvantages of CMOS and turnkey lines and show preliminary results for Si cells made in the CMOS line.
