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According to the Intergovernmental Panel on Climate Change (IPCC), there is a need to carry out in-depth research into the potential for renewable energy as part of international efforts to combat climate change and reduce dependency on fossil fuels. The purpose of this study is to examine long-term wind speed variability using seasonal and annual wind speed data at 32 Iranian synoptic stations from 1960 to 2005 to assess if wind power is a plausible source of renewable energy for Iran. Least-square regression methods and the Kruskal-Wallis test were used to determine the trends and decadal changes in wind speed.Esfehan province was selected for assessment of the impacts on wind power potential owing to its progressive and forward thinking in exploration of renewable energy. Wind power potential was estimated by fitting a hybrid of the Weibull distribution to the 3 hourly wind data.This assessment revealed a declining trend in annual wind speeds in the central part of Iran and an increasing trend near the Iranian borders during the study period. The patterns on seasonal and annual scales were generally similar.The results indicated a similar pattern of wind power variation for stations in Esfehan province, except Ardestan. The monthly wind power potential from November to January and from February to May may be representative of the low and high periods of wind energy, respectively. Consequently, despite the existence of wind speed variability and general declining trends across Esfehan province, wind energy may be explored further over the coming years by employing modern wind turbines that require lower start-up speeds.

Hydrogen gas sensors, based on palladium membranes, have considerable applications in areas such as industry, aerospace, and green energy monitoring. In this paper, we propose a surface plasmon resonance nanosensor, in which the main metal sensor is taken to be gold with a thin nanolayer of palladium membrane. The reason we chose palladium is its exceptional property of having high permittivity to hydrogen penetration. In this paper, formation of palladium hydride (PdH x , where x = H / Pd) is achieved and simulation is provided using Materials Studio software.Based on an intermediate assumption, a semiconductor gold composite layer is used instead of gold, because the composite layer gives higher efficiency. In the final structure, twelve alternating layers of gold and silicon are used (silicon and gold with thicknesses of 0.53 and 13.6 nm, respectively). The proposed structure is simulated under carbon monoxide exposure to analyze its cross-sensitivity to other gases. Finally, the sensor shows higher sensitivity and narrower linewidth under hydrogen exposure compared to carbon monoxide exposure.