using photovoltaic systems is gradually expanded by increasing energy demand. abundance and availability of this energy, has turned to one of the most important sources of renewable energy. unfortunately, photovoltaic systems have two big problems: first, those have very low energy conversion efficiency (in act between 12 and 42 percent under certain circumstances). second, the power produced b...

abstract the aim of this survey is to compare utilization systems (cooperative, private and governmental) methods of energy consumption in soybean production and the evaluation of energy inputs effect in yield of soybean in moghan. for this purpose, the information were collected from 54 private farmers, 14 cooperative members farmers and 14 agro-industry units by questionnaire method. the maxi...

the aims of this study were to investigate the energy flow and its modeling in shablon cultivar of plum production in golestan province of iran. data were collected through questionnaires and also interviews with producers. cobb-douglass model and sensitivity analysis were used to determine the effects of energy inputs on plum yield. the results revealed that the total energy inputs and energy ...

the aims of this study were to assess the energy and economic flows of biodiesel production from olive pomace oil using transesterification method with ultrasound waves. for this purpose biodiesel production from this feedstock were examined through a life-cycle process with considering five main stages of agricultural production, transportation, olive oil extraction, pomace oil extraction and ...

the use of renewable energy in power generation and sudden changes in load and fault in power transmission lines  may cause a voltage drop in the system and challenge the reliability of the system. one way to compensate the changing nature of renewable energies in the short term without the need to disconnect loads or turn on other plants, is the use of renewable energy storage. the use of ener...

the objectives of this research were to investigate influences of energy inputs and energy forms on output levels and evaluation of co2 emissions for hazelnut production in guilan province of iran. moreover, the sensitivity analysis was done by marginal physical productivity (mpp) method for energy inputs and energy using linear regression. initial data were collected from 120 orchardists in se...

nowadays the position of the renewable energy is so important because of the environment pollution and the limitation of fossil fuels in the world. energy can be generated more and more by the renewable sources, but the fossil fuels are non-renewable. one of the most important renewable sources is the wind energy. the wind energy is an appropriate alternative source of fossil fuel. the replacem...

abstract intensive and inefficient use of energy leads to degradation of natural resources and environmental problems. this study evaluated the relationship between the energy of consumed inputs and yield of tomato, cucumber and melon using the cobb–douglas production function. the data were collected from 90 farmers in firoozabad using a questionnaire. the farmers were chosen by simple random ...