Economic Evaluation of Renewable Energy Systems for the Optimal Planning and Design in Korea – A Case Study

In this study, an engineering economics software was developed to find the optimum design of renewable energy systems in micro-grid, off-grid, and on-grid cases. The software was used to calculate the renewable energy production from photovoltaic and wind turbines in local regions in Korea. TMY2 files were made for the renewable energy calculation based on meteorological data from 28 locations in Korea. To calculate the output of the photovoltaic and the wind turbine, a power generation model based on theoretical equations was developed. A fuel cell and diesel engine generator can be selected to use as a base power source model, and a battery energy storage device was included for efficient energy management. To verify the results of renewable power generations from solar and wind, the models were compared with commercial programs such as TRNSYS and HOMER. The results showed good agreement under the same conditions. A sensitivity analysis for a grid-connected factory in a specific region was carried out and the optimum investment design condition for a renewable energy system to reduce costs through peak load reduction was calculated. The sensitivity analysis for off-grid and grid-connected system designs was also performed and it will be continued to improve the accuracy of the model by comparing the data with that from a demonstration complex. The developed program can provide useful information for investment decisions through the optimal design of facility capacity and economic analysis when investing in renewable energy supply facilities.