Novel tool for PV system sizing allows users to assess tradeoffs between reliability and costs

Scientists from Egypt have developed a new software for PV system sizing that reportedly offers users information about the tradeoffs between system reliability and its costs.

Dubbed Green Energy Solutions, the software was developed using C sharp language, with 2023 prices in US dollars for the different system components.

“The new software includes new features not available in other photovoltaic software available in the market, such as the reliability of the system and producing the options to the user to choose the optimum solution according to the reliability, initial cost, and total cost for the lifetime of the project,” the researchers explained.

The software assumes PV modules to have a lifetime of 24 years, with the inverters and the batteries being replaced every 5 and 3 years, respectively.

In its user interface, the program asks the user for a few parameters. First, it asks for the system location to determine the solar radiation throughout the year. The user then needs to decide whether the system is independent or connected to the grid and whether the modules are fixed or use single or double-axis tracking.

The user is also required to choose the load and its profile from three load profiles. “Constant Load means the load is constant 24 hours, 365 days per year,” the scientists explained. “Daily Load means the load is operated from sunrise to sunset every day, 365 days per year; while Night load means that the load is operated from sunset to sunrise every day, 365 days per year.”

Based on those inputs, the system produces several outputs, such as the required size of the PV array, the battery size needed in case of a stand-alone system, and the project's required surface. It also calculates the cost/kWh generated from the system in US dollars, including loan costs.

“The reliability cost results enable the user to choose the suitable solution for the PV system according to his budget,” the researchers added. “The program illustrates that a slight decrease in reliability will result in a significant system cost reduction. For example, if the reliability is increased from 97.83% to 99.52%, the cost is increased by 88.5%.”

Finally, the research group has compared the monthly kWh/m2 calculated by its program with that calculated by PVsyst, which is a globally popular software package to study, size, simulate, and analyze data from PV systems.

According to their results, Green Energy Solutions' simulation error margin compared to PVsyst ranged from 1.46% in May to 9.06% in January. In yearly calculation, the novel program was off by 0.44%.

The software was introduced in the article “Developing Techno-economic GUI-based Software for On-grid and Off-grid Photovoltaic Systems Sizing,” published in Ain Shams Engineering Journal. The research group includes scientists from the Ain Shams University, the Misr International Technological University, and the Sadat Academy for Management Sciences.