Predictive Modeling for Rooftop Solar Energy Throughput: A Machine Learning-Based Optimization for Building Energy Demand Scheduling
Abstract The intermittent and fluctuating nature of solar energy is the biggest challenge facing its widespread utilization. Implementing onsite photovoltaic systems as alternative energy sources have established the need for reliable forecasting procedures to improve scheduling and demand management. This paper presents a solar energy prediction algorithm to optimize the available solar energy resource and manage the demand-side accordingly. The algorithm utilizes Support Vector Regression (SVR), a machine learning technique, validated using 1-year energy consumption data collected from an office building instrumented as an experimental testbed facility. Power meters and temperature sensors collect the building's internal climate and energy data, while a solar photovoltaic array and a weather station provide the external relevant data. The forecasting method uses the average power output of k-similar days as an added input to the SVR model to enhance its performance. The day-ahead prediction results show that this additional input contributes to higher forecasting efficiency, especially in the hot climate regions, where sunny weather conditions prevail throughout the year. The photovoltaic output prediction accuracy for the sunny days is above 90%, which offers possibilities for optimized scheduling and leading to smart building energy management. Finally, this paper also proposes a setpoint optimization algorithm for the building Air Conditioning system to minimize the difference between the building energy load and the generated solar photovoltaic power. Using 24 °C as the upper setpoint temperature limit reduces the energy demand (consumption) by up to 29% and the associated reduction in CO2 emissions.