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[1] This study is a proof of concept of the sensitivity of grassfire propagation to vertical shear in the near-surface environmental flow found through four comparative grassfire numerical simulations with a coupled wildfire-atmosphere model. A unidirectional constant wind field, under neutral atmospheric conditions, no surface friction, Coriolis force or topography, and homogeneous fuel, prescribes the model environment. By using the same surface (at 6.2 m above ground level) wind speed for all simulations, analyses of the results can suggest when the behavior and spread rate of the fire may depend more on the interaction of the fire plume with the shear in the above surface wind or more on the magnitude of the mean upstream surface wind speed at the surface. Three aspects of wildfire behavior are investigated: impact of unidirectional vertical shear on surface flow properties and fire line propagation; variability in fire spread and area burnt due to the evolution of the surface flow; and implications of low-level vertical wind shear on the prediction of wildfire, especially extreme or erratic, behavior.

To conserve freshwater resources, domestic and industrial wastewater is recycled. Algal systems have emerged as an efficient, low-cost option for treatment (phycoremediation) of nutrient-rich wastewater and environmental protection. However, industrial wastewater may contain growth inhibitory compounds precluding algal use in phycoremediation. Therefore, extremophyte strains, which thrive in hostile environments, are sought-after. Here, we isolated such an alga - a strain of Synechocystis sp . we found to be capable of switching from commensal exploitation of the nitrogen-fixing Trichormus variabilis , for survival in nitrogen-deficient environments, to free-living growth in nitrate abundance. In nitrogen depletion, the cells are tethered to polysaccharide capsules of T. variabilis using nanotubular structures, presumably for nitrate acquisition. The composite culture failed to establish in industrial/domestic waste effluent. However, gradual exposure to increasing wastewater strength over time untethered Synechocystis cells and killed off T. variabilis . This switched the culture to a stress-acclimated monoculture of Synechocystis sp ., which rapidly grew and flourished in wastewater, with ammonium and phosphate removal efficiencies of 99.4% and 97.5%, respectively. Therefore, this strain of Synechocystis sp . shows great promise for use in phycoremediation, with potential to rapidly generate biomass that can find use as a green feedstock for valuable bio-products in industrial applications.

Fossil-fuel processing and consumption contaminates air, soil, and water resources through the release of hazardous chemicals. The harnessing of renewable energy resources and development of sustainable technologies have become prime targets of research and increased investment to protect the environment. The use of bio-based feedstocks in energy production provides a valuable pollutioncurbing pathway with sustainability credentials, especially when wastewater is used to provide the nutrient requirements. The filamentous cyanobacterium Trichormus variabilis has attracted substantial attention from researchers due to its potential for dual industrial functions in bioenergy production and bioremediation. This species can use the power of sunlight energy efficiently to fix atmospheric CO 2 and to generate valuable chemical compounds, such as carbohydrates and fatty acids, which can be converted to biofuels. As it grows in nutrient-rich wastewater (industrial effluent) it can serve as a bioabsorbant and replace costly chemical catalysts and nano-materials traditionally used for the removal of nutrients and metals. However, no recent review has presented the potential for state-of-the-art T. variabilisdriven phycoremediation-bioenergy production systems. This review suggests possible routes from phycoremediation to energy production as a strategy for developing the industrial application of T. variabilis. It brings important research results on this species together and highlights major related challenges and opportunities. It explores the current status of the use of algae in bioremediation and the production of liquid and gaseous fuels utilizing wild-type and mutants of T. variabilis. Finally, key points underlying the potential for future research on optimization of robust technologies for supplying sustainable bioenergy using this organism are presented.

One of the main factors in the alternative fuel economy is the primary raw materials. Importing raw materials and preparation conditions for cultivation of non-native species require high expenditure. Therefore, using native species can greatly reduce production costs. Therefore in this paper, this is for the first time a comprehensive study indigenous oil plant of Tehran province and their suitable growth conditions is presented. Then three species non-edible rapeseed, cotton and barley were selected due to their feasibility of producing biodiesel. The purpose of this study is therefore to propel relevant policies in the country towards greater use of domestic raw materials and known potentials. Therefore, the potential for biodiesel production from plant sources, in this region was studied using GIS software. The present paper describes the zoning map and identifies the potential map of producing biodiesel from indigenous plant sources in Tehran province. According to the map, concentration of biodiesel production is in the central and western cities of province. This map shows that 116806.8665 hectare of land with the greatest potential to produce biodiesel. Also the potential of biodiesel production from introduced species, considering the yield per hectare and their oil content, was calculated. The results show that the potential of biodiesel production for the three species of rapeseed, cotton and barley are respectively 98117.77, 58403.43, 83516.91 tons in Tehran province. Non-edible rapeseed with the highest production potential has been introduced as a superior indigenous species for the future investments in biodiesel production in Tehran province.

This study analyses the expansion of solar energy in Iran, considering political, economic, social, and technological factors. Due to the prolonged sanctions on Iran, the development of clean energy power plants has been either halted or significantly reduced. Hence, this study aims to identify barriers to the expansion of solar energy power plants and simulate solar power plants using PVsyst (Photovoltaic system) software. The study is unique in its approach of combining technical analysis with social sciences to facilitate the implementation of solar energy expansion in remote areas. This study focuses on two specific areas with high solar radiation, namely Darab and Meybod, which are located in Fars and Yazd provinces, respectively. Solar energy can be generated in these two areas due to their unique location with high levels of solar irritation. To achieve this goal, the technical analyses focuson simulating the performance of a 9 kWp (kilowatt ‘peak’ power output of a system) grid-connected polysilicon(poly-Si) photovoltaic plant for Darab and a 9.90 kWp plant for Meybod. The simulation is carried out to obtain maximum electricity production and evaluate parameters such as incident radiation, performance ratio, energy into the grid, energy output at the array, and losses. The produced energy for Darab was 20.40 MWh/year, with specific production of 2061 kWh/kWp/year, and the performance ratio (PR) was 81.26%. For Meybod, production was 20.70 MWh/year, with specific production of 2091 kWh/kWp/year, and the performance ratio (PR) was 80.88%. Through the PEST analysis, it is evident that strategic planning and appropriate actions are crucial at the provincial, national, and local levels for energy systems’ development. This indicates that both governments and citizens should play an active role in supporting the expansion of energy systems by planning and creating awareness among the public to embrace and adopt energy systems.