Research On Renewable Energy Resources For Power Generation And Its Control Strategies

Energy, a fundamental necessity of today‘s lives, flow from several sources, drives all thesystems and available in variety of interchangeable forms. Most of the population in everycountry of the world is totally dependent on an uninterrupted and ample supply of energy fortheir living and working environment. The economic and social stability of any countrystrongly depends upon the availability of energy. Undoubtedly energy is one the most powerfuldevices to drive a nation from a developing to a developed nation or from stable to more stableposition.Nuclear Technology and fossil fuels are the core sources of global energy production sincedecades in many developed and some of the developing countries of the world. Utilization ofnuclear technology for energy production in developing countries faces a lot of big hurdles,like; high cost, technology barriers, and international restrictions etc. Also these nuclear plantsproduce nuclear waste which causes serious environmental issues. Fossil fuels, with the currentexploitation rate, are expected to exhaust within the next few decades. The continuous use offossil fuels is also destined to pollution, and thus greenhouse gas emissions and climate changeeffects will dominate the entire earth soon. The environmental degradation, rise in energy price,supply uncertainties, and nuclear energy problem are making energy trends to be unsustainableand hence a better balance between energy security, environment protection and economicdevelopment is very necessary. It is therefore advisable to exploit new, long-lasting,indigenous, cheap and clean sources of energy. Renewable energy sources, such as; wind,solar, biogas, geothermal, tidal etc. are the best choice in current situation. Renewable energysources, being native and indefinite energy sources have the potential to provide enduringsolutions to the hitches faced by environmental and economic sectors of a country. Pakistan is blessed with abundant renewable energy resources and potential of almost everytype of renewable energy, such as; solar, wind, biogas, geothermal, biomass, waste to energy,tidal/ocean energy, etc., is available in these country. The prime objective of this research workis to explore, analyze and evaluate the renewable energy resources and their power generationpotential in Sindh Pakistan.Assessment of solar energy resources has been conducted for potential location is southernregion of Sindh. Nine new models has been established to predict diffuse solar radiation ontilted surface since measured solar diffuse data is not available. The best model was chosenbased on test results from statistical indicators. The optimum tilt angle for monthly, seasonally,half-yearly and yearly adjustment was determined. The optimum tilt angle varies from0inMay, June and July to49in December. The yearly optimum tilt angle was found as23. Themonthly average total, beam and diffuse solar radiations were calculated for optimum andvertical tilted surfaces and were compared with those obtain for horizontal surfaces. The half-yearly adjustment of optimum tilt angle is recommended for the investigated location becausevery small difference in annual solar energy gains in comparison with monthly or seasonaladjustment. The total annual energy for completer year and for four seasons of the year wascalculated and found that maximum total annual energy is obtained at optimum tilt angle.Technical and economical evaluation of wind energy resources of Babaurband, Hawksbay andGharo locations, in southern region of Sindh, has been carried out. Real time wind datacollected from the investigated locations for the years from2003to2011has been consideredin this research work. Weibull distributions of wind data and Weibull parameter estimationmethods for all three locations have been analyzed. Power generation through wind turbines ofdifferent manufacturer along with cost analysis has also been done. The annual mean wind speed is more than5m/s for Gharo site. The most probable wind speedis9.356m/s while the wind speed carrying maximum energy is11.43m/s. The wind power andenergy densities are more than260W/m2and2300kW/m2respectively. The direction of windat Gharo is westerly for almost all five year. The GE45.7wind turbine generates high annualenergy of11.220GWh with capacity factor of0.56. The estimated cost of per kWh of energy isUS$0.0255.The yearly mean wind speed of Babaurband site is6.712m/s and has power density of310W/m2at80m height with high power density during April to August (highest in May with windspeed9.595m/s and power density732W/m2). The estimated cost of per kWh of electricityfrom wind is calculated as0.0263US$/kWh.The yearly mean wind speed at Hawksbay, Karachi is5.9m/s and has power density of197W/m2at80m height with high power density during April to August. The estimated costper kWh is US$0.0345.Analysis and comparison of seven numerical methods to determine the Weibull scale and shapeparameters for the available wind data for the candidate locations is presented in this researchwork.