Design and Analysis of a Grid-Tied Solar System with Deferrable Air-Conditioning Load for Lahore, Pakistan

This research investigates the structure and performance testing of a solar power system set up at a house in the Lahore, Pakistan. The system comprises Canadian Solar Max Power CS6U-340M solar panels with a top capacity of 7.50 kW and an average daily output of 28.9 kWh. The study incorporates recent proposed changes by NEPRA, including adjustments to grid rates for fed-back power. The current rate of WAPDA is 8 cents per kWh, whereas the proposed rate considered in this study is 3.9 cents per kWh. These adjustments result in a decrease ROI that can be by adding deferrable loads, such as heat-pump load. The designed system effectively handles an electrical load of 16.00 kWh/day, reaching renewable penetration of 81.9%. The yearly average power output fed back to the grid ranges from 0.40 kW to 1.2 kW, with seasonal variations leading to a production of 0.5 kW to 1.7 kW. The system purchases an average of 1.4 kW from the grid while selling back 2.4–3.4 kW. A comparative analysis between the old and new design reveals the economic implications of the government’s reduction in electricity buyout rates for consumers, emphasizing the system’s cost-effectiveness. The introduction of deferrable heat pump loads shows a positive impact on the overall production and sustainability of the system. These findings confirm that a hybrid solar power system is an economically viable and environmentally friendly choice for residential power generation.