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Photovoltaic (PV) is one of the fastest growing electricity generation technologies in the world. Average annual growth rates of global PV-installations have reached around 45% for the last 15 years, which triggered a fast and ongoing reduction of production cost in PV industry. The presented work aims at consolidating historical price and cost information, deriving refined learning curves for PV modules and systems, and analysing the main factors of learning. For c-Si modules a valid learning rate of 17% is found based on a meta-analysis of various studies. In early years, even a learning rate of 30% is observed. As an example for thin-film PV, CdTe module cost reduce by 16% as the cumulated production output doubles. Interestingly, efficiency improvements contribute only in second order to the overall cost reduction for both technologies, emphasising the relevance of production excellence and economies of scale. On PV system level, a cost reduction of 14% per doubling of cumulated installed capacity is derived. Finally, a sensitivity analysis reveals that learning rate variations are only of minor influence on the overall global PV market potential. 26th European Photovoltaic Solar Energy Conference and Exhibition; 4697-4702

In recent years, in order to promote the independent development of the new energy vehicle industry, Chinese government has decided to reduce the consumption subsidies for new energy vehicles until the subsidies are completely withdrawn. The reduction of consumption subsidy has a great impact on the production and sales of new energy vehicles in the whole vehicle market. However, does the reduction of this subsidy also have an impact on other enterprises in the new energy vehicles industry chain? This paper tests this problem using data from 2016 to 2018, and finds, through empirical analysis, that during the period of subsidy decline, the profitability of component enterprises is significantly positively correlated with this subsidies, while the r&d investment of enterprises is significantly negatively correlated with this subsidies. The results show that in terms of profitability, the reduction of consumer subsidies not only has an impact on the whole vehicle industry of new energy vehicles, but also has an adverse impact on the core component companies in the industrial chain. However, in terms of r&d, the reduction of subsidies has more negatively strengthened the input and attention of R&D in component companies.

A new concept of a system for Combined Heat and Power generation is presented. The concept is based on hybrid use of two renewable energy sources, direct solar (thermodynamic solar) and biomass (indirect solar energy). Biomass combustion is conducted using a fluidized bed combustor. A second source of energy, given by the direct irradiation of the bed with a concentrated solar radiation, is integrated in the same system, using the fluidized bed as solar receiver. A Stirling engine converts heat into mechanical power. A Scheffler type mirror is adopted to allow irradiation of the system in a fixed focal point. Advantages of the proposed solution are illustrated and some preliminary results on the performance of the system, obtained with a simple model, are presented. The principal improvements with respect to existing systems of similar size and primary energy source are illustrated. The most important are the enhanced heat transfer processes that are realized with the help of the fluidized bed, and the possibility of continuous cogeneration during the day. Different working conditions are considered to estimate the contribution given by the burning of fuel, in presence as well as in absence of sun irradiation (as during the night). The distribution of energy shares among the different flux contributes is reported versus the amount of biomass burned per unit time. The results clearly demonstrate the advantage of coupling, in the same system, two sources for heat generation, thus maintaining the option of producing electricity without the supply of biomass fuel.

We have attained superior quality a-SiGe:H and nc-Si:H materials deposited at high rate, ~0.6 nm/s for a-SiGe:H and 1-1.5 nm/s for nc-Si:H, and achieved improved multi-junction solar cell performance. For a-SiGe:H based cells, we have focused our effort on further improving the a-SiGe:H film quality by carefully optimizing process parameters, particularly with Ge content and profile, hydrogen dilution, deposition pressure and substrate-tocathode distance, to fabricate a-SiGe:H films with low defect density and good stability. For nc-Si:H based solar cells, we have mainly worked on improving the spatial uniformity and homogeneous properties for nc-Si:H deposition, and on optimizing the plasma process and selecting species to deposit further improved nc-Si:H. We attained 10.1% and 11.2% stabilized efficiencies, respectively, for large-area (≥400 cm2) encapsulated a-Si:H/a-SiGe:H/a-SiGe:H and a- Si:H/nc-Si:H/nc-Si:H triple-junction cells. Comparison between a-SiGe:H and nc-Si:H based technologies and future improvement will be presented. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 2783-2787

In this paper we argue for the need to apply a cognitive approach to understand deep dynamics and determinants of technological evolutions. After examining main contributions from innovation studies to the conceptualization of innovation and change in complex socio-technical environments, we highlight the contribution coming from the application of the cognitive approach to evolutionary studies on technologies and we introduce the concept of technological memory as an interpretative tool to understand those changes. We discuss our hypothesis with reference to several observations carried out in different local contexts – Mexico, India and Italy – in relation to technological change in the water sector. In those cases deliberate attempts to substitute traditional technologies with modern ones led to interesting trajectories of change ranging from the collapse of old technologies to the development of multifaceted hybridization patterns. Tema. Journal of Land Use, Mobility and Environment, 2014: INPUT 2014 - Smart City: planning for energy, transportation and sustainability of the urban system

Programmed Logic Controller (PLC) is the digital calculation operation system, which is specially designed for industrial working environment. This paper proposed the implement of hydraulic control system for large-scale railway maintenance equipment based on PLC. This implement pursued the purpose of accurate control of hydraulic working units of large-scale railway maintenance equipment. Large-scale railway maintenance equipment should always work in efficient statement. Focusing on this requirement, the reliability design of hardware for current leakage and impulse current which is proposed in the paper is necessary. This paper proposed Triple Modular Redundancy (TMR) for relative horizontal check of working units linking bridge. This paper also proposed the method to prevent the current leakage and impulse current. As for hydraulic valves, this paper proposed PID algorithm to realize the control of Analogue Closed-Loop.

Laser Grooved Buried Contact (LGBC) solar cell technology is an attractive way for the production of solar cells designed to operate at one sun. Although LGBC cells can have higher efficiency when compared to standard screen-printed solar cells, a more complex manufacturing process is required, increasing their relative costs. In the FP6 EU funded project “Lab2Line,” screen print and LGBC solar cell processing techniques are hybridized in order to produce lower cost high efficiency solar cells processed on large area mono-crystalline wafers, using techniques scalable to industry. Two hybrid approaches have been considered: in the first, screen-print (SP) is applied for both rear and front contacts; in the second process SP is applied only to the rear and then electroless plating is used to form the front contacts. Both Lab2Line hybrid approaches offer high average efficiencies with a small performance distribution, while simultaneously presenting a more compact, cost effective option to production. The combination of SP techniques with LGBC processes and electroless plating has led to a maximum efficiency of 17.34% for the first process and 18% (17.44% average on 171 wafers) for the latter. Modules having such cells result in FF of 79.0% and efficiency of 17.0%. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 1660-1664

It has to be considered that dynamic performance of Super Capacitor and Battery hybrid energy storage system is poor and the output waveform of AC voltage distorted seriously. The Third Harmonic Injection PWM (THIPWM) with the three-level inverter, which has a excellent performance to improve the dynamic performance of the super capacitor and battery, gathers information from ends of the DC output voltage or current and the total current of the DC side to solve the problem of unbalanced neutral line voltage of three-level inverter .It also keeps super capacitor and battery controlled smoothly during the operation, and reduces the final output waveform distortion index. The simulation results verify the practicality and correctness of the three-level inverter topology and its control algorithm.