Photovoltaics International Papers

One of the most important ways in which inorganic thin-film photovoltaics (TFPV) and organic photovoltaics (OPV) can distinguish themselves from more conventional crystalline silicon photovoltaics (c-Si PV) in the marketplace is through the commercialization of flexible photovoltaic products using those technologies. But flexible photovoltaics brings with it some challenges of its own in terms of excluding air and moisture from the cells; challenges that translate into opportunities for suppliers of advanced encapsulation materials and systems as well as for TFPV and OPV firms.

As yet, procedures for long-term tests of photovoltaic modules in outdoor conditions have not been considered by international standardization committees. Although many laboratories perform long-term PV outdoor tests, a commonly agreed and standardized procedure has so far not been adopted. The European Distributed Energy Resources Laboratories’ (DERlab) approach to filling the gap of international standardization has led to the development of a basic protocol that complies with European and international standards, while providing specific common guidelines and procedures for measuring the energy yield of PV modules for at least one year in outdoor conditions. The DERlab procedures for long-term PV module testing are described in this paper, and the range of analyses that can be derived from the data, such as module degradation, are discussed. The paper also presents the DERlab approach to measuring module performance in outdoor conditions, which can be used to complement energy-rating methods suggested in international standards. DERlab has created consistent measuring procedures that allow the direct comparison of the energy yield of solar modules taking into account the site-specific factors of different locations and varying climatic conditions, as well as a maintenance guideline.

One of the busiest of the couple-dozen solar manufacturing factory floors I’ve seen this year belonged to ECD Uni-Solar, at its Auburn Hills 2 (AH2) facility just up the road from the Palace where the NBA’s Detroit Pistons play hoops. When I toured the plant in late July, the three production areas – cell deposition, cell finishing, and module stringing/lamination/final assembly – were humming, as the 1.5-milelong rolls of flexible stainless-steel starting material were transformed into triplejunction amorphous-silicon thin-film PV laminates. The company’s latest quarterly results confirm those observations at the factory, as production output grew some 58% over the previous period – from 21.2MW to 33.6MW – pushing capacity utilization to about 90%.

The recent 30% decline in module market prices is the most telling sign of a need for continuous reductions in PV production costs. With this in mind, the cost efficiency of production processes is, next to stable product quality, a vital objective in the planning of production facilities. In this paper, the lessons learned in the area of cost of ownership (COO) forecasting methodologies will be analyzed and evaluated for their potential application to investment decisions in the PV industry. This paper will analyze the cost structure of the PV industry with the aim of underlining the importance of a systematic cost-of-ownership approach.

A major challenge for the solar industry over the next few years is the reduction of production costs on the road to grid parity. Capacity must be increased in order to leverage scaling effects, production and cell efficiency must also be enhanced, and the industry must focus on intensified process optimization and quality control. Laser marking can make a key contribution to fulfilling these requirements. As hard physical coding, laser marking is applied to the raw wafer at the start of the manufacturing process, making each solar cell traceable along the entire value chain and over its whole lifetime. This paper presents Q-Cells’ laser-supported process for coding each individual solar cell (European patent pending), which will require transition work at the laboratory stage before the company’s innovation is ready for mass production.

The U.S. solar PV market is suffering not from a lack of demand or high prices, but rather from an inconsistent labyrinth of rules and regulations which complicate and prolong uptake. There is significant pent-up demand in the U.S. among developers and especially manufacturers; there is not, however, a commensurate regulatory framework that will enable and encourage this demand to be realized. The U.S. political landscape is deeply divided, and policies that would directly or indirectly effect solar demand are no different from any other in this regard.

The minority carrier lifetime is a key parameter for the performance of solar cells as it characterizes the electrical quality of the semiconductor material. Consequently, accurate and reliable methods to determine the minority carrier lifetime are of enormous interest for both practical process control and the evaluation of the potential and limitations of a specific cell concept. Due to its importance, many different lifetime measurement techniques have been developed and used over the past few decades. This paper aims to present and discuss the most common measurement methods on the one hand, while attempting to shed light on some recent developments on the other. The determination of the minority carrier lifetime of crystalline silicon thin-film (cSiTF) material is illustrated as an example of interest for those who are already familiar with standard lifetime characterization.

The next generation of industrial silicon solar cells aims at efficiencies of 20% and above. To achieve this goal using ever-thinner silicon wafers, a highly effective surface passivation of the cell, front and rear, is required. In the past, finding a suitable dielectric layer providing a high-quality rear passivation has been a major challenge. Aluminium oxide (Al2O3) grown by atomic layer deposition (ALD) has only recently turned out to be a nearly perfect candidate for such a dielectric. However, conventional ALD is limited to deposition rates well below 2nm/min, which is incompatible with industrial solar cell production. This paper assesses the passivation quality provided by three different industrially relevant techniques for the deposition of Al2O3 layers, namely high-rate spatial ALD, plasma-enhanced chemical vapour deposition (PECVD) and reactive sputtering.

Despite the financial crisis and present credit crunch, photovoltaic materials markets experienced only a temporary slide in demand in 2009, with the overall outlook remaining optimistic. This paper presents a strategic analysis review for the materials used in photovoltaic modules, essentially materials for encapsulant, frontsheet, backsheet and anti-reflection coatings. Rising concerns about the need to reduce CO2 emissions and increase the use of renewable energy sources worldwide will stimulate the global photovoltaic market. Feed-in tariffs and politically backed targets boosting renewable energy use will provide further impetus to the photovoltaic market. This, in turn, will have a positive ripple effect on the demand for photovoltaic materials; however, depending on the market share for technology used, i.e. crystalline or thin film for PV energy, the market for materials will be influenced, in addition to advantages and disadvantages of these materials that will influence their market share. With rising awareness about green trends, the future will lie in technologies that offer enhanced energy-efficient solutions at a low cost. Manufacturers who offer products with optimum performance while remaining price-orientated will be poised to gain substantial market share.

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 article is the second of a two-part series shedding light on how U.S. integrators contribute to a decreasing installed-PV-system cost roadmap by championing value creation in the downstream segment. Focusing on the residential market segment, Part I delved into activity cost savings through innovation in engineering and construction [1]. Part II illustrates how changes in marketing and sales, rebates, interconnection, supply chain management and customer support have evolved considerably over the last several years to result in reduced costs.