"Hybrid Energy SystemAs its name suggests, thehybrid system means the combination of two or more differentelements. So, here hybrid energy system is basically the combination of two or more energyresources such as PV (Photo Voltaic) Cell, diesel generators or wind generators.1) Need of Hybrid Energy System in Rural Areas? Hybrid energy system seems to be the best solution for Power generation inthe rural areas where the extension of the grid system is mainly uneconomicalto install. The Hybrid system helps in providing the electricity at a low costas the price of PV Cells are decreasing day by day so we can use them inrural electrification.? As the data says, about 1.5 billion people in the world, who still do not haveany access to electricity and they mainly rely on cow dung, firewood, andagricultural residue for their daily households. The fuel cost is increasing dayby day, so the use of PV cells is more advantageous as their cost is decreasingday by day. ? The Demandfor energy in rural areas during night hours are limited, and insmall regions, energy is not even served during nights.? In hybrid systems, batteries are mainly used to store energies so that we canutilise them later if there are some undesired weather conditions.? Windmills do water pumping in some rural areas. As we know that winds aremostly in winters, so here is the problem. Now to eliminate this issue we needthe Hybrid System to overcome these seasonal problems. In PV cell and windturbine combination, it will produce more efficient and effective output.? In India, about 70% of India’s Population lives in rural areas, and theirprimary support of livelihood is Agriculture. So, to bring the improvement inthe agriculture field, we must use the Hybrid system of the Mechanical typewhich will help in proper irrigation and other works. 2) Functions of the Hybrid system:The Solar PV-wind hybrid system is mainly used where there is the seasonal shifts ofsunlight and wind occurs. Like the wind, do not blow throughout the day and for the entireday, thesun does not shine. Therefore, using a single source out of them will not be a suitablechoice. A hybrid arrangement is combining the power from both the sources (wind andsunlight) and stored them in a battery will be a much more reliable and realistic powersupply. When there is no source like wind or sunlight is there then we can still power them byusing batteries. Hybrid systems are usually built to minimise the cost and to maximise thereliability. The main feature of wind turbines as compared to PV cells is their low lost wherewe can use wind turbines the most. During the day time battery systems are used to storesolar and wind energy. During night hours, the presence of wind seems to be an addedadvantage, which helps in increases the reliability of the system. Figure 1:- Diagrammatical Representation of Solar SystemComponents of the system: -? PV system? Wind turbines? Batteries ? Inverter 1) Photovoltaic (PV) System consists of Solar Panel, which basically converts thesunlight into electricity. PV Cells are made up of semiconductor structures. Whenthe sun rays got absorbed by this, they tend to emit electrons from the atom.Hence, this will produce current. This is known as a ‘Photoelectric’ effect inwhich solar power is convertedinto electricity. In a solar cell, it consists of adifferent number of panels, which are connected in either series or parallel. Figure 2:- Generation of Electricity from Solar Cells2) Wind turbines are mainly used to convert wind energy into electric power. Theenergy produced by wind turbines is depended upon the wind power.3) Batteries are the system we use to store energy so that we can use that energywhen sunlight and the windare not there due to some severe weather conditions.We can get any required capacity by connecting batteries in either series orparallel.4) Inverters are used to reload the energy stored in the batteries and will convert DCpower into AC power.Implementation of the Hybrid system: -Let us see one example of existing Installation of the Hybrid system in Nonthaburi Thailand(on a small scale) [1] Resources used for the system were? Amorphous Silicon PV Module of 1642 watts was used.? Permanent magnet wind turbines of 1000 watts were used.? LabVIEW was used as the PC based monitor system.? This project took three months for its completion.? 83.30% and 82.44% were the efficiencies of the inverter.Installations are as following1) Get all the required information2) Obtain all the wind data of the site: - In this, their main step was to get allthe wind data so that PV connected system should work well. The primarydata collected was the speed of the wind and its direction. For their project,they use 3-cups anemometer (Novalyx) of 30 meters high, and forcollecting information every five minutes, they used the data logger. Theaverage wind speed was found to be 4.570 mph (2.04 m/s). The highestand lower average wind speed was found to be 7.205 mph (3.22 m/s) and2.207 mph (0.98 m/s) respectively.3) Designing of the small PV hybrid system: - For this small inverter andwind turbines were taken. It requires separating the inverter from the PVside because there is a voltage difference between the wind turbine and DCbus of a PV module as shown in figure 3.The power required for installation was equal to 1642 W. Apollo 300model, 220V, 50Hz, 2.2Kw has used the grid connected inverter. Figure 3The small PV systemAnother example (on a large scale): -PV Hybrid System for Rural Areas ThailandFirstly, a survey was conducted in rural areas of Thai it was found that some rural areas donot have any access to electricity. Then the Ministry of Interior was given this project, andthey set the goal of completion of the project to 2005-2006.System Designing part:The system was described under 3 operation modes. In the first mode when solar energy willbe good enough to generate electricity and can directly be supplied to the load. In the secondmode when there is no battery and solar energy then the system will use the energy of thegrid lines. In the third mode System Voltage Considerations:System voltage varies from system to system and is depends on the size of the system. Forlarge size systems; voltage must be 480-600 V, for the medium sized system; voltage must be120-240 V, for small size system; voltage must be 12-48 V. There were four villages thatwere selected for the project in the different parts of the Thailand: - ? In Western Thailand: - Bann Bon Khao Kang Liang Village? In Eastern Thailand: - Bann Koh Jia Island? In Northern Thailand: - Bann Pa Ya Sai Village? In Southern Thailand: - Bann Klong Rua VillageOut of them, Bann Pa Ya was a very small so; the system voltage was selected to be 24V. Other villages were selected with the voltage of 96 V.Table 1:- Representation of the Peak power(kWp) and Battery capacity(kWh) of all villages Now let us consider the more examples of Rural Areas: -1) Papago Indian Village, Schuchuli, Arizona: -The World’s first renewable systemof 3.5 KW PV array, was installed in 1978 to produce electricity for a community. 2) Natural Bridges National Monuments, Utah: - When PV system was not there inUtah’s Monument, it generally consumed up to 200,000 kWh of electricityannually, and it causes a lot of noise and air pollution. But in 1980, with theimplementation of PV systems, it consumes now 70,000 kWh annually.3) Kotzebue, Alaska: - The main objective here was to bring electricity to rural areasof Alaskan Communities. As the cost of fuel was very unaffordable so, addingwind turbines lead to saving of fuel in large amount. Since 1998, the KotzebueElectric Association wind farm was working. It has 6 diesel generators with itscombined capacity of about 11.2 MW. "