DESIGN AND ANALYSIS OF A HYBRID RENEWABLE MICROGRID SYSTEM FOR MINE SITES IN SOUTHWEST OF MONGOLIA

Abstract

This thesis focuses on the design and analysis of a renewable microgrid system for mines in the southwest of Mongolia, with an emphasis on addressing the energy-intensive nature of mining, diesel use, and CO2 emissions. As a country abundant in renewable energy resources, Mongolia presents a unique opportunity to achieve sustainable solutions in the mining sector. However, despite proven renewable technology and a renewable-rich country, most mining companies have yet to adopt renewable solutions. The methodology employed in this study encompasses several key steps. Firstly, an overview of the legal frameworks and regulations about renewable energy deployment in the mining sector in Mongolia is conducted. Next, a concept design phase is undertaken, integrating solar, wind, energy storage, and diesel generators to create an off-grid hybrid system tailored to the mine's energy requirements. Considerations such as load demand, resource availability, and system reliability are taken into account during the design phase. Modeling and simulation techniques are employed to assess performance and feasibility, evaluating various scenarios to meet energy needs while minimizing diesel fuel usage and CO2 emissions. Furthermore, a detailed business case is developed, considering the initial capital investment, operational costs, and potential financial benefits of the renewable microgrid system. The analysis includes factors such as the payback period, return on investment (ROI), and levelized cost of electricity (LCOE), providing insights into the economic viability of the system for mining operations in Mongolia. The analysis revealed that incorporating a wind turbine in the off-grid hybrid system increased the renewable energy fraction from 28.6% (PV + energy storage) to 88.1% (PV+ energy storage + wind turbine), resulting in a significant reduction in the levelized cost of electricity (LCOE) and operating costs over the life of the mine. However, PV energy systems with a peak capacity of 6 MW offered a more reliable and consistent energy source compared to wind turbines due to low wind speeds and higher installation costs associated with taller hub heights (>50m).