Assessment of Electrical Energy Demand for Water Heating and Performance Optimization Using Photovoltaic Panels

Abstract

Hot water plays a vital role in numerous human and industrial applications, yet its production is often associated with significant environmental impacts. This growing demand underscores the importance of sustainable alternatives. Solar energy, as a clean and renewable resource, has emerged as a promising solution to mitigate these environmental effects. Libya, with its abundant solar radiation and favorable climatic conditions, offers an optimal setting for harnessing solar energy to generate electricity for water heating purposes. This paper presents calculating the number of photovoltaic (PV) panels required and the electrical energy generated to support water heating. The study was conducted in Brega, where solar irradiance reaches a peak intensity of 980 W/m², utilizing PV panels with an area of 1.65 m² installed at a tilt angle of 45°. The system design included a 40-liter water storage tank and was tested on June 15, 2024, over a 5-hour period. The results demonstrated encouraging feasibility, with the panels generating 1.2 kWh of electrical energy, while the thermal energy demand to heat the water was 1.4 kWh. These findings confirm that PV panels can serve as an effective and sustainable means for water heating, particularly in regions with high solar irradiance such as Libya. Future optimization of the system, including enhanced panel design and storage solutions, could further improve efficiency, making solar-powered water heating a viable alternative for both residential and industrial applications.