Techno-economic evaluation of a grid-connected microgrid system

Abstract

The availability of solar resources has led to the utilization of photovoltaic (PV) system for the generation of a clean electricity and reduction of greenhouse gas (GHG) emissions. The techno-economic assessment of a medium scale microgrid system is investigated in this work by utilizing some key performance indicators (KPIs). These KPIs are used as the benchmarks to study the economic impacts of PV in the grid-connected power system for 10 selected locations across the nine provinces of South Africa. The HOMER package is utilized in the study to obtain viable solutions that will mitigate the undesirable technical and economic issues that come up during the grid integration. The research work is carried out by utilizing the surface meteorology and solar energy data provided by the National Aeronautics and Space Administration (NASA) for assessment of the proposed microgrid system. The outcomes of the study show that the annual average daily radiation varies from 4.3 kWh/m2/day in Durban to 5.749617 kWh/m2/day in De Aar. It is deduced from the work that De Aar is the most feasible location among the 10 selected sites for the installation of PV in terms of cost of energy (COE), net present cost (NPC), net energy purchased, energy purchased, energy sold, energy charge, annual utility bill savings and revenue with the following values: 0

Design and analysis of a photovoltaic‐battery ‐ methanol‐diesel power system

“…The PV system converts solar radiation into electrical energy by utilizing the photovoltaic effect. Solar radiation is one of the prominent data that is essential for development of an effective solar energy conversion system and estimation of its power generation capacity 7 . The annual average solar radiation and a clearness index of the atmosphere for the selected site are found to be 5.47 kWh/m 2 /day and 0.56.…”

“…The average solar radiation and clearness index on a monthly basis are shown in Figure 5A while Figure 5B shows the monthly temperature of the selected site over a 1‐year period. The hourly power generated by the PV system can be calculated by utilizing the following equation 7,33 : where PV rated represents the rated capacity of the PV array (kW), PV DF depicts the derating factor of the PV (%), I represents the solar radiation incident on the PV panel (kW/m 2 ), I STC represents the incident radiation at standard test conditions (STC) (1 kW/m 2 ), T depicts the PV cell temperature (°C), T STC represents the PV cell temperature at STC (°C) and α p is the temperature coefficient of power (%/°C) respectively.…”

“…It is the portion of the solar radiation that passed through the atmosphere to strike the Earth surface. The clearness index can be expressed in Equation (4) as 7 : where I av is the monthly average solar radiation (kWh/m 2 /day) and I o,av is the extra‐terrestrial horizontal radiation (kWh/m 2 /day) respectively.…”

“…The output power of the BS can be estimated by using Equation (5). 7 where N bs , V bs and denote the number of batteries, storage's nominal voltage (V) and storage's maximum charge current (A) respectively.…”

“…The myriad utilization of RERs for power generation application has become a potential alternative to meet the global power demand 7 . Nevertheless, the design and deployment of RERs such as solar and wind resources have become a great challenging task for the microgrid operators (MGOs) owing to their intermittent and availability 8,9 .…”