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The Danish energy system is undergoing a transition from a system based on storable fossil fuels to a system based on fluctuating renewable energy sources. At the same time, more of and more of the energy system is becoming electrified; transportation, heating and fuel usage in industry and elsewhere. This article investigates the development of the Danish energy system in a medium year 2030 situation as well as in a long-term year 2050 situation. The analyses are based on scenario development by the Danish Climate Commission. In the short term, it is investigated what the effects will be of having flexible or inflexible electric vehicles and individual heat pumps, and in the long term it is investigated what the effects of changes in the load profiles due to changing weights of demand sectors are. The analyses are based on energy systems simulations using EnergyPLAN and demand forecasting using the Helena model. The results show that even with a limited short-term electric car fleet, these will have a significant effect on the energy system; the energy system’s ability to integrated wind power and the demand for condensing power generation capacity in the system. Charging patterns and flexibility have significant effects on this. Likewise, individual heat pumps may affect the system operation if they are equipped with heat storages. The analyses also show that the long-term changes in electricity demand curve profiles have little impact on the energy system performance. The flexibility given by heat pumps and electric vehicles in the long-term future overshadows any effects of changes in hourly demand curve profiles. International Journal of Sustainable Energy Planning and Management, Vol 7 (2015)

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government has decided to reduce the consumption subsidies for new energy vehicles until the subsidies are completely withdrawn.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.

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

Department of Chemistry, Jai Narain Vyas University, Jodhpur-342 001, Rajasthan, India E-mail : krg2004@rediffmail.com Manuscript received 1 June 2006, revised 15 January 2007, accepted 17 January 2007 Brij-35, DTPA and Bismark Brown were used as surfactant, reductant and photosensitizer respectively in photogalvanic cell and photogalvanic effect was studied. The photopotential and photocurrent generated by this system were 786.0 m V and ll5.0 µA respectively. The observed conversion efficiency, fit! factor, cell performance in dark and maximum power obtained were observed 0.5192%, 0.48, 117.0 min and 54.00 µW, respectively.

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.

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.

According to the characteristics of photovoltaic cell output power curve, this paper analyzed and explained the principle of Maximum Power Point Tracking (MPPT) and both advantages and disadvantages of constant voltage tracking method & perturbation observation method. Further, in combination with the advantages of existing maximum power tracking methods, this paper comes up with an improved tracking method which is recognized as maximum power point tracking combined with constant voltage tracking method & variable step-size perturbation observation method. The Simulink simulation results have proven this enhanced tracking method has a better performance in System response and steady state characteristics.

A new and applicable environmental rating tool for use as a policy tool, called EcoScore, was developed and allows evaluating the environmental impact of road vehicles with different drive trains or using different fuels. A single environmental indicator integrates different aspects of the environmental impact of the vehicles such as global warming, air quality depletion and noise pollution. To integrate these different aspects, the Ecoscore methodology includes different damage categories like: global warming, human health impairing effects and harmful effects on ecosystems. The contribution of the different normalised damages to the single value, called Ecoscore, is based upon a weighting system. The methodology can also be used for the ranking of heavy duty vehicles and two-wheelers. However, in this paper, the methodology will be explained using passenger vehicles and light-duty vehicles as an illustration. The methodology will be implemented by the Flemish government as a policy tool for the promotion of cleaner vehicles. An extensive database including vehicle records and their related emission data was used to develop, to validate and to analyse the environmental rating system. A sensitivity analysis was carried out which allowed the evaluation of the robustness of the methodology.

Valence band offset and valence band bending at the p+ hydrogenated amorphous silicon/n-type crystalline silicon (a-Si:H(p+)/n_c-Si) interface in heterojunction silicon solar cells (HIT) induce a p+ inversion layer which pushes the pn junction 20-25 nm deep in the c-Si side. The heavily hole populated interfacial inversion layer acts as the HIT cell emitter while the ultrathin amorphous silicon layer is the front contact. The impact of doping level and dangling bond defects in the a-Si:H layer and of interface states on the inversion layer properties is investigated by means of AFORS-HET simulations. Apart from the electric field created by the conduction band offset, the HIT cell performs like a c-Si solar cell which has an inversion layer emitter matching that of the HIT cell, with an open circuit voltage of 733 mV. The latter rolls off at relatively large interface (front surface) recombination velocity. Increasing the a-Si:H(p+) doping level modifies the peak hole concentration in the inversion layer and increases the front surface field. On the other hand, c-Si cell with an ultrathin dopant diffused emitter having also the same emitter hole profile sees its performance degraded at relatively low surface reombination because it suffers from bandgap narrowing and from doping dependent mobility degradation and has no front surface field. Inserting an ultrathin intrinsic or lowly doped a-Si:H spacer between a-Si:H(p+) and c-Si provides less hole population in the inversion layer which reduces Auger recombination and improves the open circuit voltage at low surface recombination to 735 mV despite the less effective front surface field. 28th European Photovoltaic Solar Energy Conference and Exhibition; 822-826