الملخص الإنجليزي
Renewable energy has an increasing role in achieving the goals of sustainable development, energy security, and control of greenhouse gas emissions. Wind energy is the most popular form in use for electricity production due to a steady advancement
of wind power technology with a decline in total costs. Furthermore, new designs and sizes of blades and generators have enabled investments in very low wind speed areas. The same advances have encouraged Daleel Petroleum Company to look into utilizing wind energy at its oil operation fields.
Daleel fields are flat and free of obstacles. The wind speed and wind power density average 3.7 m/s and 53.859 W/m2, respectively, at measurement height level (8 meters). This study has assessed the wind energy potential at 80 meters in height
(turbine hub height), and it has determined the wind speed and energy at hub height to be around 5.1 m/s and 136 W/m2, respectively. In the wind energy market, there are mainly four types of wind turbines, each with different sizes of generator and blade lengths. This study has reviewed them and recommended the type C doubly-fed induction generator (DFIG) and type D full-scale converter for Daleel wind farm project as they can harvest the energy of the very low wind speeds of Daleel's fields. Moreover, it has selected, on the basis of site-matching methods, the 3.4MW wind turbine with 140-meter rotor diameter for the wind farm. This study has determined six 3.4MW wind turbines as the number of the turbines needed for meeting the anticipated future load of Daleel's Fields. To achieve maximum output of the wind farm, it has advised distributing the wind turbines in a matrix layout with a 1.26Km spacing distance between turbines. The designed wind farm is expected to generate around 38.8 GWh/year, equal to 27.7% of Daleel's annual consumption of electricity. It will save approximately one million OMR (1.16) in operating expenses (OPEX) for Daleel's electrical system. Furthermore, it will reduce around 21,728 tons of the carbon dioxide emission produced from the power plant. The electrical system of the wind farm has been designed to transmit the energy harnessed by the wind turbines via a network of low- and high-voltage cables and step- up transformers to the point of common coupling. Moreover, the wind turbines are fitted with current controllers, which enable the turbines to inject reactive current for support of the grid during network faults, and they are provided with reactive/voltage controllers for grid compliance during steady-state operations.
This report has studied the impact of the designed wind farm on the existing protection system of Daleel micro-grid. The study has observed that the designed wind farm blinds the operation of overcurrent relays in Daleel power plant for the three-
phase fault on OHL at a 30Km and greater distance. Hence, the study has advised adjusting the time and current pick-up settings of a few protection relays. In the end, this study has evaluated the economics of the designed wind farm based
on very simple methods such as payback period (PBP), internal rate of return (IRR), and net present value (NPV). It has concluded that Daleel Company can invest in wind energy for achieving short PBP, high IRR, and high NPV if the following market
parameters are met:
1- The discount rate is between 5% and 7%.
2- The capital cost ranges from 352.66 to 553 OMR/KWh.
3- Electrical losses are no more than 15%.
