Surendra Kothari

Bio: Surendra Kothari is an academic researcher from Maharana Pratap University of Agriculture and Technology. The author has contributed to research in topics: Solar dryer & Solar energy. The author has an hindex of 11, co-authored 26 publications receiving 2377 citations.

Role of renewable energy sources in environmental protection: A review

Abstract: Renewable technologies are considered as clean sources of energy and optimal use of these resources minimize environmental impacts, produce minimum secondary wastes and are sustainable based on current and future economic and social societal needs. Sun is the source of all energies. The primary forms of solar energy are heat and light. Sunlight and heat are transformed and absorbed by the environment in a multitude of ways. Some of these transformations result in renewable energy flows such as biomass and wind energy. Renewable energy technologies provide an excellent opportunity for mitigation of greenhouse gas emission and reducing global warming through substituting conventional energy sources. In this article a review has been done on scope of CO2 mitigation through solar cooker, water heater, dryer, biofuel, improved cookstoves and by hydrogen.

State of the art of solar cooking: An overview

Abstract: Cooking is the prime requirement for people all over the world. It accounts for a major share of energy consumption in developing countries. Solar energy is contributing major energy requirements of the world's population particularly in developing countries. Among the different energy end uses, energy for cooking is one of the basic and dominant end uses in developing countries. There are number of solar energy based cooking appliances has been design, developed and tested for various applications across the globe. In this paper attempt has been made to provide comprehensive view on standard testing approach of solar cooker, energy and exergy analysis approach and economic evolution of different types of solar cooker. Thermal performance of box type and concentration type solar cookers in both laboratories and actual field conditions also rigorously reviewed and presented in this paper.

Solar greenhouse an option for renewable and sustainable farming

Abstract: Greenhouses provide a suitable environment for the intensive production of various crops. They are designed to provide control as well as to maintain solar radiation, temperature, humidity and carbon dioxide levels in the aerial environment. CO2 enrichment decreases the oxygen inhibition of photosynthesis and increases the net photosynthesis in plants. This is the basis for increased growth rates caused by CO2 at low as well as at high light levels. Elevated CO2 concentrations also increase the optimal temperature for growth. The maximum crop response depends on the level of the balanced environmental parameters. Off seasonal cultivation is quite possible in greenhouse and it improves economic conditions of farmers. This paper reviews the available worldwide thermal modeling for heating, cooling and ventilation technologies and experimental studies of agricultural greenhouses.

Experimental investigation of drying of garlic clove in solar dryer using phase change material as energy storage

Abstract: This investigation deals with thermodynamic analysis, which offers an alternative approach to evaluate the performance of solar dryers and thin-layer drying characteristics of garlic cloves in a developed system. The garlic cloves were dried from a moisture content of 55.5 % (w.b.) to 6.5 % (w.b.) for 8 h. The drying data obtained were fitted to five different drying kinetics models. Of these, the model suggested by Midilli et al. [28] had the best fit with the drying behavior of garlic cloves. The energy efficiency without and with recirculation of the air exiting the drying chamber during the study varied from 43.06 to 83.73 %, and 3.98 to 14.95 %, respectively, while the exergy efficiency corresponding to the energy efficiency of the drying process ranged from 5.01 to 55.30 % and 67.06 to 88.24 %, respectively.

A review on energy and exergy analysis of solar dying systems

Abstract: Solar energy is a clean, abundant and freely available renewable energy sources. Energy and exergy analysis of solar thermal devices has drawn considerable interest among the researchers across the world. Solar drying is the promising option to utilize low grade energy to dry agricultural produces. Exergy analysis is a tool to access the efficient usage of solar energy. It is the property of the system, which gives the maximum power that can be distracted from the system when it is brought to a thermodynamic equilibrium state from a reference state. Using exergy analysis, based on the first and second laws of thermodynamics, it is possible to infer the true potential of different kinds of energies. In this paper, a holistic approach on energy and exergy analysis of solar dryer with case studies has been made.

A review of renewable energy sources, sustainability issues and climate change mitigation

Abstract: The world is fast becoming a global village due to the increasing daily requirement of energy by all population across the world while the earth in its form cannot change. The need for energy and its related services to satisfy human social and economic development, welfare and health is increasing. Returning to renewables to help mitigate climate change is an excellent approach which needs to be sustainable in order to meet energy demand of future generations. The study reviewed the opportunities associated with renewable energy sources which includes: Energy Security, Energy Access, Social and Economic development, Climate Change Mitigation, and reduction of environmental and health impacts. Despite these opportunities, there are challenges that hinder the sustainability of renewable energy sources towards climate change mitigation. These challenges include Market failures, lack of information, access to raw materials for future renewable resource deployment, and our daily carbon footprint. The ...

Catalyzing the Hydrogen Evolution Reaction (HER) with Molybdenum Sulfide Nanomaterials

Abstract: We discuss recent developments in nanostructured molybdenum sulfide catalysts for the electrochemical hydrogen evolution reaction. To develop a framework for performing consistent and meaningful comparisons between catalysts, we review standard experimental methodologies for measuring catalyst performance and define two metrics used in this perspective for comparing catalyst activity: the turnover frequency, an intrinsic activity metric, and the total electrode activity, a device-oriented activity metric. We discuss general strategies for synthesizing catalysts with improved activity, namely, increasing the number of electrically accessible active sites or increasing the turnover frequency of each site. Then we consider a number of state-of-the-art molybdenum sulfide catalysts, including crystalline MoS2, amorphous MoSx, and molecular cluster materials, to highlight these strategies in practice. Comparing these catalysts reveals that most of the molybdenum sulfide catalysts have similar active site turnov...

Defects Engineered Monolayer MoS2 for Improved Hydrogen Evolution Reaction.

Abstract: MoS2 is a promising and low-cost material for electrochemical hydrogen production due to its high activity and stability during the reaction. However, the efficiency of hydrogen production is limited by the amount of active sites, for example, edges, in MoS2. Here, we demonstrate that oxygen plasma exposure and hydrogen treatment on pristine monolayer MoS2 could introduce more active sites via the formation of defects within the monolayer, leading to a high density of exposed edges and a significant improvement of the hydrogen evolution activity. These as-fabricated defects are characterized at the scale from macroscopic continuum to discrete atoms. Our work represents a facile method to increase the hydrogen production in electrochemical reaction of MoS2 via defect engineering, and helps to understand the catalytic properties of MoS2.

Solar energy for future world: - A review

Abstract: World׳s energy demand is growing fast because of population explosion and technological advancements. It is therefore important to go for reliable, cost effective and everlasting renewable energy source for energy demand arising in future. Solar energy, among other renewable sources of energy, is a promising and freely available energy source for managing long term issues in energy crisis. Solar industry is developing steadily all over the world because of the high demand for energy while major energy source, fossil fuel, is limited and other sources are expensive. It has become a tool to develop economic status of developing countries and to sustain the lives of many underprivileged people as it is now cost effective after a long aggressive researches done to expedite its development. The solar industry would definitely be a best option for future energy demand since it is superior in terms of availability, cost effectiveness, accessibility, capacity and efficiency compared to other renewable energy sources. This paper therefore discusses about the need of solar industry with its fundamental concepts, worlds energy scenario, highlights of researches done to upgrade solar industry, its potential applications and barriers for better solar industry in future in order to resolve energy crisis.