Photovoltaic module prices have typically decreased faster than projections. There are two methods usually used for these projections; cumulative market shipment experience curves or detailed ...bottom-up cost calculations for specific technologies. The former suffers from a lack of specificity in terms of technology or changing market situations, and the latter from a lack of quantifiable uncertainty. We present an alternative bottom-up future cost model for a new vertically integrated c-Si PV factory, from poly silicon to module, incorporating input ranges and uncertainty via a Monte Carlo analysis. Neglecting profit margins, the majority of projected scenarios for global 2025 module manufacturing cost fall between 0.10 US$/W and 0.18 US$/W, due mostly to reductions in raw materials costs for module fabrication. The lowest 10th percentile projections, below 0.10 US$/W, would be realised by the largest scale manufacturers with access to very low materials costs and low operational costs. The model projects production cost learning rates between 29% and 43% compared to a long-term historical average module selling price learning rate of 24%. Analysis of the competitive position of silicon heterojunction cell technology in combination with multi-wire module technology is performed. Access to the multi-wire technology improves competitiveness of 2025 manufacturing in high labour rate countries if silver prices remain high and the cost of the multi-wire material is reduced in line with other materials, motivating continued development of this technology. Finally, continued reduction in labour intensity, through automation and throughput will enable more competitive manufacturing in higher labour cost locations.
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•Spectrum of projected future costs of PV module manufacturing with uncertainty.•2025 c-Si PV manufacturing at < $0.18/Wp should be possible in most of the world.•Technology leadership and automation can compensate for higher operational costs.•Comparison of next generation PV technology in the future market landscape.
Restricting the light escape angle within a solar cell significantly enhances light trapping, resulting in potentially higher efficiency in thinner cells. Using an improved detailed balance model for ...silicon and neglecting diffuse light, we calculate an efficiency gain of 3% abs for an ideal Si cell of 3-μm thickness and the escape angle restricted to 2.767° under AM1.5 direct illumination. Applying the model to current high-efficiency cell technologies, we find that a heterojunction-type device with better surface and contact passivation is better suited to escape angle restriction than a homojunction type device. In these more realistic cell models, we also find that there is little benefit gained by restricting the escape angle to less than 10°. The benefits of combining moderate escape angle restriction with low to moderate concentration offers further efficiency gains. Finally, we consider two potential structures for escape angle restriction: a narrowband graded index optical multilayer and a broadband ray optical structure. The broadband structure, which provides greater angle restriction, allows for higher efficiencies and much thinner cells than the narrowband structure.
Retrograde melting (melting upon cooling) is observed in silicon doped with 3d transition metals, via synchrotron‐based temperature‐dependent X‐ray microprobe measurements. Liquid metal‐silicon ...droplets formed via retrograde melting act as efficient sinks for metal impurities dissolved within the silicon matrix. Cooling results in decomposition of the homogeneous liquid phase into solid multiple‐metal alloy precipitates. These phenomena represent a novel pathway for engineering impurities in semiconductor‐based systems.
Elemental silicon is extracted through carbothermic reduction from silicon-bearing raw feedstock materials such as quartz and quartzites. We investigate the micron-scale distribution and valence ...state of iron, a deleterious impurity in several iron-sensitive applications, in hydrothermal quartz samples of industrial relevance during a laboratory-scale simulated reduction process. We use X-ray diffraction to inspect the quartz structural change and synchrotron-based microprobe techniques to monitor spatial distribution and oxidation state of iron. In the untreated quartz, most of the iron is embedded in foreign minerals, both as ferric (Fe
3+
,
e.g.
, in muscovite) and ferrous (Fe
2+
,
e.g.
, as in biotite) iron. Upon heating the quartz to 1273 K (1000 °C) under industrial-like conditions in a CO(g) environment, iron is found in ferrous (Fe
2+
) particles. At this temperature, its chemical state is influenced by mineral decomposition and melting processes, whereas at higher temperatures it is influenced by the silicate melts. As the quartz grains partially transform to cristobalite 1873 K (1600 °C), iron diffuses towards liquid–solid interfaces forming ferrous clusters. Silica is liquid at 2173 K (1900 °C) and the iron migrates towards the interfaces between gas phases and the silicate liquid.
We propose a safety qualification program for vehicle-integrated photovoltaic (VIPV) modules, which could serve as a simplification, thereby accelerating the homologation process of new vehicle ...designs. The basis is the current photovoltaic (PV) module safety qualification, as defined in IEC 61730:2016, which is compared to automotive norms and regulations because additional safety requirements have to be considered for PV modules used in this application. Therefore, testing based on regulations that concern electrical and electronic equipment in vehicles (ISO 16750), rupture safety of glass and laminated glass in vehicles (ECE R43), and pedestrian safety (ECE R127) are assessed and compared in terms of severity. Additionally, optional testing concerning the long-term stability of VIPV modules is recommended, as a guideline for vehicle manufacturers. If assessed to be necessary, the qualification program of IEC 61730 is complemented by the respective tests to finally present a conclusive safety qualification program for VIPV modules in new vehicle designs.
Technology innovation and successful market introduction and impact carries the risk that future market conditions may not be as predicted. For PV technologies, the future industry cost of ...manufacture has been demonstrably hard to foresee, which can result in a poor assessment of the future competitiveness of a technology in development today. Future projections of PV cell and module manufacturing cost will always have significant uncertainty and this is not quantified in standard bottom-up cost-of-ownership calculations. To address this, we have built a Monte-Carlo based cost-of-ownership model to simulate reasonable future scenarios of manufacturing cost for c-Si cells and modules 1. In this contribution, we analyze the cost/benefit of high-efficiency cell technology as a function of Ag usage, Ag cost, and manufacturing location. We find that at current and most likely future Ag costs, a high efficiency cell technology like silicon heterojunction (SHJ) with higher Ag usage will be more economically competitive in both Europe and China in the future. However, in Europe the SHJ benefit is less sensitive to changes in Ag cost and higher efficiency cells should be more competitive in higher labour cost locations.
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