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This paper investigates the climate change impact on cooling energy consumption of office buildings in four major architectural climate zones in China. The results show that there are apparent differences in the responses of monthly or yearly cooling loads to climatic change in different climates. Dominant factors affecting monthly cooling loads change from dry bulb temperature (DBT) to wet bulb temperature (WBT) with the climate zones changing from severe cold to hot. The yearly cooling load was mainly afftectd by DBT in severe cold climate, whereas the WBT had the dominant effect in the other climates. With the continuous warming climate, the yearly cooling load did not rise significantly for any climate zone except for severe cold climate zone where cooling load had a significant increase ( p  < 0.01). More importantly, the cooling load showed a weak decrease in Guangzhou. These results suggest that different measurements for buildings cooling energy conservation should be made in different climate zones. The humidity effect should be fully considered to improve buildings energy efficiency, especially in the hot climate zones. The continuous increase of temperature in the future does not necessarily increase cooling loads of buildings in the cold, hot summer & cold winter and hot summer & warm winter climate zones, and change trendency of humidity in the future need to be considered to predict cooling energy consumption. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the different parameters that affect solar still productivity when the solar still productivity is very low compared with other desalination systems, such as other thermal processes or membrane processes. These parameters include environmental, design and operational parameters. The results show that productivity was highly affected by environmental parameters due to the unpredictability of metrological factors. When design and operational parameters were varied, increases in productivity were observed. The results indicated that the solar still was inversely affected by evaporation area, water depth, a minimization in the angle of the solar still cover during summer seasons and maximization during winter seasons. Stepped solar still techniques enhanced the productivity, and the addition of wicks in a stepped solar still was proposed. Insulating the sun tracking system positively affected the productivity because the insulation increased the heating capability and evaporative effects inside the still basin. [ABSTRACT FROM AUTHOR]

Climatic parameters obtained from the meteorological measurements over a long period represent a start position for monitoring and forecasting climate changes in the future. The paper observes monthly values of climatic parameters such as minimum and maximum air temperature ( T min , T max ), precipitation, wind speed at 2 m height ( u 2 ) and actual vapor pressure ( e a ) from twelve meteorological stations in Serbia during the period 1981-2010. Parameters T min , T max and e a constantly increase in the observed period. However, precipitation and u 2 decreased during the last decade. Changes and spatial distribution of monthly precipitation, T min and T max were observed during the crop growing season (April-September) in the last decade. [ABSTRACT FROM AUTHOR]

Abstract: Recently, the International Commission on Illumination (CIE) has adopted a range of 15 standard sky distributions representing the whole probable spectrum of actual skies in the world. Each sky standard has its own well-defined sky luminance pattern which can be conveniently used to calculate the sky radiance and luminance for a given sky patch and the solar irradiance and daylight illuminance on inclined surfaces facing various orientations. The crucial issues are whether the skies could be correctly identified. This paper presents the work on the classification of the CIE Standard General Skies using various climatic parameters and indices. Meteorological variables namely luminance distribution for the whole sky including zenith luminance, global, direct-beam and sky-diffuse illuminance on a horizontal surface and vertical sky illuminance, and horizontal and vertical solar irradiance data are adopted for analysis. The results demonstrate that there are a number of appropriate climatic parameters for sky classification and the selection depends on their availability, accuracy and sensitivity. The approaches could contribute to the estimation of solar irradiance and daylight illuminance which are essential to the renewable and sustainable developments and energy-efficient building designs. [Copyright &y& Elsevier]

Abstract: This paper introduces a dynamic prediction of solar radiation and ambient temperature. Medium term prediction is based on climatic parameters behaviours during the day before and on time distribution models. As for short term prediction, it is ensured by an ARMA predictor using Kalman filter. Herein, we describe our method and present prediction results. Validation is based on measures taken during the year 2005 in the north of Tunisia. The work effectiveness is illustrated by a short term and medium term prediction of the electric energy produced by a 1KWp photovoltaic panel (PVP) installed at the Energy and Thermal Research Centre (CRTEn) in the north of Tunisia. Since our work delivers accurate climatic parameters prediction, the obtained results can be easily adapted to predict any other solar conversion system output. [Copyright &y& Elsevier]

In studying solar energy and daylight availability, particularly the sky luminance distributions, the required data are always analysed under various sky types which are categorised by some climatic parameters. Overcast days are important because they are used in more general sky models and appear quite frequent in some places. This paper studies some common climatic parameters including cloud cover, sunshine hour, solar irradiance, daylight illuminance and sky luminance and their applications in the classification of sky conditions. Frequency of occurrence of each parameter under overcast skies in Hong Kong has been established. It has been found that no single parameter can effectively describe the fully overcast skies and hybrid indices should be adopted. The general luminance distribution formula for the overcast sky with various luminance distribution parameter values has been used to test the selected sky luminance databases. The analysis indicates that the CIE standard overcast sky shows a good agreement with the overcast sky luminance distributions obtained in Hong Kong. [Copyright &y& Elsevier]