Numerical and experimental analysis of pure aluminium shear panels with welded stiffeners

In the field of passive seismic protection of framed buildings shear panels can be effectively applied as hysteretic devices. Recently, a wide experimental and numerical study has been undertaken at the University of Naples in order to investigate the behaviour of aluminium alloy stiffened shear panels. Test results show that the proposed system is characterised by a large energy dissipation capacity and therefore is suitable to be used for seismic protection of new and existing framed buildings. To simulate the hysteretic behaviour of the systems, according to the experimental tests, a refined FEM model has been set up. The comparison between experimental and numerical results shows that the adopted model is reliable enough to well interpret a number of important behavioural phenomena in terms of the main global features of the system.     

Zinc-phthalocyaninetetraphosphonic acid as a novel transparent-conducting-oxide passivation for organic photovoltaic devices

A novel monolayer chemical passivation improving the surface electronic properties of indium-tin oxide (ITO), used as an electrode in organic solar cells (OSC), is reported. Deposition of zinc-phthalocyaninetetraphosphonic acid on ITO substrates, from a water solution, creates a chemically bound organic monolayer passivation, which improves the charge transfer through the ITO/zinc-phthalocyanine (ZnPc) interface in ZnPc/C₆₀ OSC. Current–voltage measurements on devices produced on such substrates show improved serial and parallel resistances as well as fill factor, compared to OSC on non-passivated substrates. The use of this novel passivation for electrodes allows to dispose off the additional conventional PEDOT:PSS buffer layer.     

Estimation of monthly averaged direct normal solar radiation using elevation angle for any location

Light concentrators used in solar photovoltaic and solar thermal applications, and concentrates light by a factor of 10 or more, use only direct normal solar radiation, I_N. A new method, called elevation angle constant (EAC) method, is developed to determine the resource potential of I_N for different locations. This method is applicable to estimate the I_N at any location in the world. The EAC method is based on empirical relations. The method calculates the elevation angle constant (ε) for a given location and time. It uses readily available daily global and diffuse global radiation data to estimate the I_N. This is different from existing methods which invariably uses hourly global and diffuse radiation. The values of I_N are estimated for 12 locations across the world. The values of I_N obtained using the EAC method have been compared with values obtained using the model-based approach (Appendix-1). The comparison is also done with the measured values for some stations. Ninety percent of the estimated values of I_N using the EAC method for the stations like Angola, Egypt, Kuala Lumpur, Singapore, Brussels, Stuttgart, Ottawa, Birmingham, Los Angeles, Wellington, Perth and New Delhi are within ±5% of the values estimated by the model-based approach (Appendix-1).     

西藏自治区民用建筑采暖设计地方标准简介

标准结合西藏的能源供应模式和生态特点,提出通过主、被动式太阳能利用和建筑保温方法解决当地的采暖问题,主动式供暖系统以太阳能热水为主要热源;标准涉及供暖室内外计算参数的确定、热负荷计算、太阳能热水系统设计等方面,为当地民用建筑供暖制定了设计依据.     

The passive solar heated school in Wallasey. VII. Window opening behaviour and the microclimate of a classroom

Previous work on factors which influence the opening or closing of windows suggests that at low ambient temperatures movement might be associated with odour levels, at intermediate temperatures, with ambient humidity and at higher ambient temperatures with the need to cool buildings. The data on window position, together with other physical measures during the period of observation in the Wallasey School, has been examined to see what quantity is most closely associated with window position. It appears that in the classroom the number of open windows depends mainly upon air temperature, but it also depends markedly on time of day.     

Economic analysis of small photovoltaic facilities and their regional differences

Small grid‐connected photovoltaic (PV) facilities in Spain receive either a premium of 0.36€ kWh^?1 over the average price on the power market or a fixed price of 0.40€ kWh^?1. However, legislation on this matter (Royal Decree 2818/98) requires a periodic review of these figures. The basis of on‐going revision of these prices has been their profitability. However, the economic success of such PV facilities is clearly affected by the amount of solar radiation at the site where they are located. Since Spain is between latitudes 44 and 36° in the northern hemisphere, the feasibility of these systems must be analysed for different regions. Two different models have been used to produce the required input data for such an analysis: a model that generates typical solar radiation years and temperatures taken from satellite images and an empirical model for the prediction of daily power produced by a grid‐connected photovoltaic system. From the results of this regional economic analysis, it may be concluded that the existing prices are insufficient in and of themselves to make these small grid‐connected systems profitable anywhere in Spain. To guarantee the economic feasibility of these PV installations in any given location, the fixed price paid for the electricity should be around 0.93€ kWh^?1. Nevertheless, if the Government were to double the current fixed price, in consideration of the slow increase in the PV market in recent years, this would mean that small grid‐connected installations would become profitable in at least 77% of the Spanish territory. Copyright © 2004 John Wiley & Sons, Ltd.     

MATLAB modelling and examination of the effect of heat capacity of basin and glass cover on performance of solar still by thermal models

There are numerous researcher-developed mathematical models for single slope passive solar stills which considered the effect of heat capacities of basin and glass cover as negligible. The negligence parameter also plays a vital role in the prediction of the thermal performance of the system. In this paper, an effort has been made to evaluate the cumulative yield, energy efficiency and exergy efficiency of a single slope passive solar still with and without considering the heat capacities of basin and glass cover by using various thermal models such as Dunkle’s model, Zheng Hongfei et al.’s model and Tsilingiris model. These models were studied and compared with and without considering the heat capacity of solar components such as basin and glass cover. The thermodynamic model of this system is developed, and executed in a MATLAB code. By comparing the theoretical values of the cumulative yield, energy efficiency and exergy efficiency, it was found that consideration of the heat capacities of glass cover and basin gives a higher output in all the thermal models.     

Way forward in meeting energy challenges in Pakistan

In this review the energy potential of Pakistan from hydro, coal, wind, solar and nuclear sources has been discussed. The new projects that are being commissioned on coal, wind, solar, hydel and nuclear-based technologies have also been mentioned. The review has also explored the future prospects of the country’s energy requirements. Pakistan has potential to produce 100,000?MW of electricity from Thar coal for 20 years, 56,000?MW of hydroelectricity, 150,000?MW of wind energy and ～50,000?MW from solar sources. The coal-fired power generation is expected to 11,500?MW in period 2017–2019. The country is moving in the right direction to cater its energy needs. However, there is a need to find local and foreign investment in the country to meet high energy demands in the country in future.