K. V. S. Rao

Wind turbine failure analysis for wind farm at Devgarh in Rajasthan

Wind turbine failure analysis is necessary for efficient operation and maintenance of machines in a wind farm. An analytical study related to wind turbine failures was done for a wind farm at Devgarh in Pratapgarh district of Rajasthan, India. Data related to failures were collected from the maintenance log book at wind farm site, and comparison between all the installed wind turbines was done. On analyzing failures of wind turbine components during the three years period, it was observed that failure duration of yaw motor was highest, followed by failure duration of gear-oil pump, and then failure duration of hydraulic unit of blade tip air brakes system.

Performance analysis of wind power plant at Devgarh in Rajasthan

Performance of 2.25 MW wind farm at Devgarh in Pratapgarh district of Rajasthan was studied. Parameters of analysis were energy production, capacity factor, machine availability, grid availability, and system availability of three wind turbines installed at site. The data for year 2011, and 2012 of wind farm were used in calculations. The results of this study confirm that wind farm performance could be further increased by improving grid availability, and machine availability of the wind turbines.

Techno-Economic Analysis of a Grid-Connected Hybrid Solar–Wind Energy System

Solar and wind resources are the two renewable energy sources that are generating the major portion of the renewable energy-based electricity. Both these sources are intermittent in nature when considered separately. But when solar and wind system are combined and operated in hybrid mode, the reliability of electrical system is much better in comparison with the system based on single source of renewable energy. In this paper, a grid-connected hybrid energy system (HES) consisting of solar photovoltaic (SPV) and wind energy (WE) system which is modelled to supply power to 50 MW constant load. HOMER software is used for solar–wind hybrid system modelling by considering five cases in which the load share of SPV are 0, 30, 50, 70 and 100%, while remaining percentage of load is supplied through wind energy system. Soda site at Jaisalmer, Rajasthan (India), is considered for installing the Solar PV–Wind hybrid system. The variations in net present cost and levelized cost of electricity are analyzed by varying turbine loss factor and grid power purchase price. It was estimated that the renewable fraction is maximum for the hybrid system in which share of each of solar and wind energy is 50% of the load, if turbine losses are taken into consideration. Assuming the power purchase price of Rs. 6/kWh from the grid and supply price of Rs. 5/kWh to the grid, levelized cost of electricity for the system is Rs. 2.92/kWh, Rs. 3.37/kWh and Rs. 3.24/kWh when the wind turbine overall loss factor is assumed as 0, 11.55 and 16.20%, respectively.

Energy Savings in a Building at Different Climatic Zones of India by Using Insulating Materials

In India, infrastructure sector presently consumes about 40% of the total generated electric energy and it is estimated to further increase by 36% to make it 76% by the year 2040. Energy consumption in buildings mainly relies upon building’s envelope. In the building sector, especially in commercial buildings: Heating, ventilation, and air-conditioning (HVAC) systems consume a major portion of the overall energy used for thermal comfort. By proper choice of thermal insulating materials, energy consumption can be reduced for winter heating and summer cooling of buildings. Expanded polystyrene (EPS) and extruded polystyrene (XPS) materials are used for the thermal insulation of buildings. In this paper, EPS and XPS insulations are selected with seven different glasses for simulations. Simulations are done with the help of eQUEST 3.63 software. Simulations for building cooling are done for five cities located in five different climatic zones of India, namely Bengaluru, Barmer, Jaipur, Thiruvananthapuram, and Srinagar. For building heating, Srinagar City is selected for simulations. EPS and XPS materials are selected for insulating walls and roof. For exterior windows, single- and double-glazing glasses are selected. Simulation results show that energy savings for various combination of insulating material and window glazing glasses are varying from 4.703 to 25.58% for cooling. In Srinagar for the heating purpose, energy savings are varying from 52.904 to 71.71%.

Levelized Cost of Electricity and Plant Load Factor of 7.5 MW Grid Connected Biomass Power Plant

Large amount of agricultural waste is produced after harvesting of crops like wheat, paddy, soya-bean, maize, mustard, sugarcane, groundnut etc. The conventional way is to burn it in the fields or dump it across the wasteland. The burning of biomass residue in the fields has very adverse effect for the environment and leads to air pollution. A more efficient way is to use biomass residues of agricultural crops for production of electricity through biomass based power plants. In India, grid connected biomass power and co-generation installed capacity has increased from 1,102 MW in 2006 to 8,182 MW in 2017. This paper analyses the twenty years’ performance of a 7.5 MW biomass power plant situated at Rangpur village near Kota city of Rajasthan, India, based on capital cost, present cost of biomass per tonne, data obtained from 2006 to 2015 related to annual power generation, and annual consumption of biomass. Levelized Cost of Electricity is found to be varying from Rs. 4.43/kWh to Rs. 4.64/kWh for interest rates varying from 8% to 16%. Plant Load Factor is found to be varying from 29% to 82% during the period of 2006-07 to 2014-15 for nine years, with an average plant load factor of 73%.

Effect of Skin Friction Coefficient on Power Developed by Flettner Rotor System for Ship Propulsion

Flow over a rotating cylinder is a complicated phenomenon. Many researchers studied boundary layer, for both laminar and turbulent flow and reported instabilities. Because of the difficulty in the determination of skin friction coefficient for flow over a rotating cylinder, the experimental and computational values obtained by different researchers are also widely not in agreement. The flow over a rotating cylinder has many applications such as in ship propulsion using Flettner rotor, motion of a missile, etc. Flettner rotor can be used as an auxiliary power source for ship propulsion. In this paper, using four different empirical relations for skin friction coefficient, power developed/consumed by Flettner rotor on a ship is calculated for different values of wind speed and ship speed. It is found that though, these empirical relations are differently proposed by authors, the numerical values obtained for power generated by Flettner rotor for ship propulsion using these four different formulae didn’t have significant difference.

Comparison of smart grid development in five developed countries with focus on smart grid implementations in India

Smart grid is the future of electricity that can revolutionize the way present electricity grids are monitored and controlled. Smart grid uses highly automated and digitized operation for real time applications. Smart grid is in its developing stage in India. National Smart Grid Mission (NSGM) was launched by Ministry of Power, that plans and monitors policies and programs for development and deployment of smart grid in India. Total of 14 pilot projects and 1 smart city project are announced so far for smart grid development in India. This paper reviews smart grid, along with its various building blocks. Australia, Canada, China, Germany, India, and Japan are comparatively studied, for smart grid development and implementation. Smart grid projects undergoing in these countries along with their technological developments are also described. The driving factors for smart grid development in these countries and India are summarized.

Relevance of hydrogen as an alternative of electricity for energy transmission and transportation of water in India

Presently the worlds energy system is moving towards the clean energy options. Hydrogen can be one of them, because of its several inherent properties. It is a clean energy vector and water is the only exhaust produced, when burnt in the presence of air. Hydrogen economy includes the replacement of fossil fuels, so that it can also help in reducing the global CO2 emission. Hydrogen provides an alternative way of storing energy similar to the electricity. This paper introduces a new concept of transmitting energy in the form of hydrogen with an added advantage of producing water. So that both the shortage of water and power can be fulfilled by a single means. In this paper, the main fields of hydrogen economy: hydrogen production; delivery; and handling of hydrogen are discussed with their economic aspects. The transmission of energy in the form of hydrogen with the cost of different phases for 200 km of transportation are also discussed. A study of sending energy in the form of hydrogen from Kota to Ajmer in the state of Rajasthan, India is also presented. Hydrogen transportation as energy provides both electricity and water at the endpoint, which is particularly useful during summer as many parts of India have both shortages of water and electricity.

Estimation of energy production and net metering of Grid connected rooftop photovoltaic system in Rajasthan

Ministry of New and Renewable Energy, Government of India in the year 2015, revised the target of solar power generation to 100 GW under National Solar Mission. But out of this 100 GW, target of power to be generated through grid connected rooftop photovoltaic power plants is 40 GW till the end of the financial year 2021–22. For achieving this ambitious target of 40 GW, a large number of rooftop systems are being installed. This paper discusses the guidelines and technical specifications of various components of grid connected rooftop photovoltaic systems that are specified by Rajasthan Renewable Energy Corporation Ltd for projects being implemented in Rajasthan state of India. Net metering and grid connectivity guidelines and procedures of distribution company of Rajasthan are also discussed. The paper also analyzes the feasibility of a 100-kW grid connected rooftop photovoltaic power plant at Rajasthan Technical University, Kota, Rajasthan. Energy production estimations are calculated using RETScreen Expert and PVWatts software using the solar radiation data files of Kota, that are available with the two software. Using the prevailing tariff of electricity for government educational institutions, an estimate of annual cost savings is calculated. The annual energy production estimations from RETScreen Expert is 174.667 MWh and that calculated using PVWatts is 180.740 MWh. The capital cost of Rs. 6 million for installation of 100 kW will be recovered in less than 5 years. Considering the life of grid connected rooftop photovoltaic power plant as 25 years, for the next 20 years, the university will generate additional revenue of Rs. 2.62 crores (Rs. 26 million) to Rs. 2.71 crores (Rs. 27 million) at the present rates of tariff for electricity in Rajasthan.

Net power generated by flettner rotor for different values of wind speed and ship speed

In global scenario, shipping and inland water transport became a very popular and necessary mode of goods transport, as it covers approximately 90% of the tonnage of all traded goods. That contributes approximately 2.8% to 3% of annual global greenhouse gas emissions, especially CO2. The marine transportation is expected to increase further more as energy demand is expected to grow by 25% from 2014 to 2040. Environmental concerns for the reduction of CO2 emission compel the shipping industry to reduce fossil fuel consumptions by increasing efficiency in shipping transportation and by adopting renewable energy sources for shipping. Wind energy for ship transportation is abundant and its potential is also high on seas. Wing sails, Airborne wind turbines, Wind kites, Flettner rotors, etc. are different techniques to harness wind energy for shipping. Flettner Rotor technique is one which provide thrust force for propelling the ship. In this paper, a cylindrical Flettner rotor (without endplates) of 12.5 m height and 2.1 m diameter is used for the theoretical analysis to estimate net power generation by Flettner rotor using the values of lift coefficient of Cl = 12.5 and drag coefficient of Cd = 0.2. Calculations have been made for ship speeds of 15 knots and 20 knots and wind speed variation from 5 m/s to 20 m/s at all true wind angles. Net power output obtained is maximum at true wind angles of 100 degree and 260 degree. At ship speed of 15 knots, the maximum values of net power obtained is 42.2 kW, 124 kW, 239.9 kW and 386.7 kW at wind speeds of 5 m/s, 10 m/s, 15 m/s, 20 m/s respectively. Whereas, at ship speed of 20 knots maximum values of net power is 68.2 kW, 189.5 kW, 358.8 kW and 575.2 kW at wind speeds of 5 m/s, 10 m/s, 15 m/s, 20 m/s respectively. Calculations have also been made for net power generation from Flettner rotor for various values of coefficient of rotation.