Design and model development of a baseload power plant in 100% renewable energy system

Abstract

Kendal Power Station is one of the baseload power stations using coal-fired power plants for electricity supply to the Mpumalanga province in South Africa which is managed by Eskom. However, the power station has become the epicenter of air pollution in this region due to malfunctioning emission infrastructure at the facility. This forced the South African government to take legal action against Eskom because the power station was found to violate the emission standards set out by the Department of Forestry, fisheries and the Environment, particularly emissions such as sulphur dioxide, nitrogen oxide, particulate matter particles and carbon dioxide. These emissions negatively affect the health of citizens in Mpumalanga province and nearby communities, leading to chronic respiratory illnesses, stroke, heart attacks, birth defects and premature death. To eliminate these emissions, this research therefore designed and modeled the development of a baseload power station using 100% renewable energy resources. The renewable energy resources comprise of hybrid model of solar PV panels, wind turbines and a pumped hydro storage system. Thus, a 4116MW renewable sources baseload power plant was designed for Mpumalanga province. A model was developed and simulated to determine the feasibility of the system. This capacity is equivalent to the nameplate generation capacity of the Kendal power station. The methodology involved included identifying a location close to the Kendal power station according to a certain criterion that is specific to the construction of a solar PV, wind turbine, and pumped hydro storage system. The Loskop dam was selected as the lower reservoir for the pumped hydro storage system. The area around the Loskop dam was the selected location for the installation of the wind turbine and solar PV system. After the design of the system, the HOMER Pro software was used for simulation, this allowed the model to be simulated using multiple parameters to decide on a system that would meet the objectives of this research. The most optimal system that met the objectives of the research consists of a combination of components such as 68 Enercon E-126 wind turbines, a capacity of 24181500kW LONGi Solar LR6-72P panels, a converter capacity of 4220000kW and a three-string battery equivalent to the pumped hydro storage system with the capacity of 98 784 000 Ah. This system was able to meet the load capacity with the lowest LCOE and zero unmet electrical loads, proving the reliability of the system. The NPC of the system was R571 000 000 000 and the LCOE was R0.889 per kWh, which is lower than the current LCOE in South Africa. The generated emissions from the system were determined to be 0 kg/year which will positively impact the health of citizens. This research can be applied in the design and development of hybrid renewable energy plants in South Africa. It can also be used by decision-makers to determine the feasibility of hybrid renewable energy systems.