NUMERICAL ANALYSIS OF SOLAR-WIND HYBRID POWER GENERATION SYSTEM

. The Solar and wind energy produce fluctuated output energy when used individually and does not ensure the base size of power continuously required by the center of load. There is a necessity of hybridization of energy sources that is feasible in terms of efficiency and economy. The combination of solar with wind energy is one of the best proven technology either with battery mode or stand alone grid connection. Benefits of utilizing hybrid solar wind turbine are manifold This paper focusses on the designing of hybrid solar wind turbine system for the power generation from solar and wind renewable sources for household purpose in the remote areas that are connected to grid. An investigation is done on the solar and wind energy harness in a required geographic space's weather data collection of solar radiation and wind speed at respective location from India. Numerical analysis of hybrid solar wind turbine, was conducted with separate standalone system due to the constraint of simulation tool. Simulations of Wind Turbine is done by computational fluid dynamics (CFD) that is found based on velocity of wind. The simulated result which is converted from kinetic form of mechanical energy that converted to electrical energy using analytical formulas. The data for simulation was collected from National thermal power corporation, Ramagundam , Indian Meteorological Department.


Introduction
A "hybrid" electric system offers several advantages over either single system.These can be stand-alone systems, which operate "off-grid" i.e., which are not connected to an electricity distribution system.Solar-Wind hybrid Power is the combination of power generated by windmill and solar energy panel.This will have a battery which stores the power solar and wind energies.Production of electric power, using windmill from wind source is available and power from PV plant, which produced from solar radiation is available can be achieved.Both solar and wind units can be utilizing power generation whenever, both sources are available in a day.An uninterrupted power supply can be achieved by attaching with battery, but we need to look at the economic feasibility, as life of batteries are limits to 2 to 3 years.The Schematic diagram of the Hybrid Power Systems is shown in the figure 1.
*Corresponding author: Anjani.padakanti@gmail.comAdvantage of using hybrid system is, it can overcome the discontinuities, imbalance and over burden of capital/installation cost etc., of non-conventional sources.These types of plants have better suits quietly across the places in glob where, there are seasonal shifts like summer, winter, spring, and autumns.This is due to availability of solar energy during daytime, local and global winds that flows on land and water surfaces only based on seasons, latitude, altitude, near to equator and away from it, therefore technically, it is not advisable to depend on single source.In recent times with advanced technologies most of the countries opting for hybrid sources so that most of the energy can be harnessed.Based on the ones country's energy policies one can go for batter backup or grid connection.The hybrid system designs are made with optimum reliability and cost, as capital cost of solar cells, place for the setup and huge tower structure of windmill components are high.Ashish S. Ingoleet al . [1]observed that hybrid energy system was, combination of two or more energy sources that, supplies power to the load.It is interpreting as system that is made to power extracting by using 2 energy sources.It has good reliability, performance, low emission, and less cost.Solar and wind power is used for generating power in his proposed system, these sources has good advantages than any other renewable energy sources.Cost can be minimized by increasing the production of the equipment.Nabil A. Ahmed et al. [2] hybrid energy framework combining variable-speed wind turbines, photovoltaic solar panels, and energy unit age frameworks to provide independent capacity to private power applications.The power device is used as an optional or backup energy source, while the breeze and photovoltaic frameworks are used as primary energy sources.The power feed to the heap is controlled by three independent dc support converters.For largest power point following and thus most extreme power separation from the breeze turbine and sun-oriented solar frameworks, a cost-effective, simple controller using DC converters have used.Farshad Golnaryet al. [3] concluded that, inlet to the numerical solution includes coefficient of heat loss, solar irradiance and, ambient temperature.The results of thermal efficiency has been compared and validated with experimental data by the calculation heat removal factor.Then the substantial approach was assigned to 5 types of inlet co-figurations to a collector's head riser, it was concluded that the most efficient de-signs has showed laminar flow throughout risers.The configurations that has low mass flow rate in risers results in high surface temperatures and poor thermal efficiency consider as poor performance.L.A. Martinez Tossas et al. [4] compared the performance of actuator disk & actuator line type that produced wind turbine wakes between multiple turbines.He examined variables that effect turbine per performance of different models like grid resolution, the use of a tip loss correction and turbine force that is projected onto flow field.finally concluded, both models gave same wake profiles and predicted power within 1% of each other subjected to uniform in flow.For thrust coefficient a agreement of 25% and 40% between the model.It is found a normalized power was similar in both, but a difference of 1 to 17 % in terms of dimensional power.Bhushanetal.[5] work was on the investigations of Lift and Drag forces for varied Reynolds number and angle of attack for wind turbine's blade.The NACA 0012 air foil profile is considered for analysis of wind turbine blade.By varying angle of attacks from 0̊ to 80̊ , Lift and Drag forces are calculated for Reynolds number from 10,000 to 800,000 CFD and conclusion was made that with the increase in Reynolds number , lift and drag forces increase.Observations of H. V. Mahawadiwaret al. [6] shows that the value of numerical power increase with increased angle of attack from 0̊ to 7, and past 7̊ numerical power's value was reduced.The blade's critical angle of attack is 7.At angle of attack 7̊ performance coefficient is maximum and at velocity of air 8 m/s.Here , the blade can generate atmost power.Observations also show that that the coefficient of performance is raised from 3 m/s to 8 m/s and after 8 m/s coefficient of performance decreases.

EXPERIMENTAL SETUP
The experiment has been carried and collected from 10 MW Solar power plant -National Thermal Power Corporation, Ramagundam.A brief overview of materials required, and the testing procedure used to study the effects on hybrid power plant performance has been presented.It provides a description of experimental data of solar radiation, wind velocity, temperature and peak load for day/month/year.Automatic Weather station gives the Global horizontal irradiation, Global tilt irradiation, humidity levels, pressure, and temperature and wind velocity at a particular location which is used in the solar power plants.The data is directly sent to the computers in the power plant administration.

ANALYTICAL FORMULAS FOR SOLAR ENERGY
The analytical formula that is used to estimate electricity generated from a photovoltaic system E is Energy (kWh), A is total solar panel Area (m2), r is solar panel yield or efficiency (%) H is annual average solar radiation on tilted panels PR is Performance ratio, coefficient for losses (range between 0.5 and 0.9, default value = 0.75),'r' is the yield of the solar panel given by the ratio, electrical power of single solar panel divided by area of one panel.Insulation material respectively in the Ansys workbench and the Geometry of the wind turbine model with enclosure.

P = 1 / 2ρ A V3
(2) P -power, ρ -air density, A -swept area = π r2 where r is the radius of the blades, V -velocity of the wind.Insulation material respectively in the Ansys workbench and the geometry of the wind turbine model with enclosure.

ANALYTICAL FORMULAS WIND TURBINE
Wind energy is a form of solar energy, and wind turbines convert the kinetic energy from wind to mechanical form of energy.It is a non-conventional source of energy that gives a total power in wind and then mechanical energy is converted into electrical energy using generator.The following is the power formula for windmill.
, 01   From the above results, it is seen that, the mean temperature of a photo voltaic panel is reduced from 322K to 300K (490C to 270C) as we know that the PV cell efficiently works at lower temperatures.The effect of wind velocity of the PV panel temperature is more when velocity is high and temperature reduces, i.e., inversely proportional.It is also observed that, the higher temperature scale reduces with slow pace and the lower temperature scale decreases a bit fast with increase in wind velocity.

EFFECT OF WIND VELOCITY ON WIND TURBINE
The velocity and pressure contours for varying wind velocity on the wind turbine in Ansys workbench is studied from following table.the wind velocity reaches 25m/s (90kmph).So, the maximum power output will be attained during 5-15m/s wind velocity and it is maintained
An enormous power can be extracted with low pollutions from solar -wind hybrid power generation plants.

2.
As the solar power cannot be acquired after certain timings of a day due to absence of day light, the wind power which doesn't have any such requirements except the wind speeds, gives us the benefits of generating power during nights also.

3.
Higher capital and installation cost is observed initially but that can be regain back within less number of years with little maintenance cost.Pow-er produced after breakeven time, it is very cheaper compared to energy availability.

Figure 2 .Figure 3 .
Figure 2. Automatic weather station Fig 2 shows the setup of AWS (automatic weather station) in 10 MW Solar power plant -National Thermal Power Corporation, Ramagundam

Figure 4 .Figure 5 .Figure 6 .
Figure 3. Drawing of Solar PV Panel with dimensions.Figure 4. Drawing of the Wind turbine

Fig. 3
Fig.3 and fig 4 shows Drawing of the Solar PV Panel. Figure 5 & Figure 6 shows the Geometry of Solar PV Panel of four layers such as Glass, Aluminium frame, Silicon Photo Voltaic cells, and Insulation material respectively in the Ansys workbench.

From
the analysis the following results has been studied for different wind velocities and are shown in fig 7a and 7b.

Figure 7a .
Figure 7a.Variation of lower temperatures With Figure 7b.Variation of higher temperatures With Wind Velocity of PV Cell Panel Wind Velocity of PV Cell Panel

Figure 8 .Figure 9 .
Figure 8. Velocity and Pressure contours for different wind velocities

Table 1 .
Monthly Solar Power Generation of Solar Power plant -NTPC, Ramagundam of FY 2017-18