Modern Applied Science; Vol. 14, No. 9; 2020 ISSN 1913-1844 E-ISSN 1913-1852 Published by Canadian Center of Science and Education 28 Experimental Study of Solar Water Heater under the Libyan Climate Conditions Ali. J. S. Alrafad 1 , Abdihg S. Alrafad 1 , Tarek. Hamad 2 & Ahmed. Nassar 3 1 Mechanical Engineering Department, High institute of Science and technology, Algobi , Altmimi - Libya 2 Department of Sustainable and Renewable Energy Engineering, Omar Al-Mukhtar University, El-Bieda, Libya. 3 Mechanical Engineering Department, Bright star university - Libya Correspondence: Ali Jibreel Saed, Mechanical Engineering Department, High institute of Science and technology, Altmimi-, Libya. E-mail: alidosh85@yahoo.com Received: March 29, 2020 Accepted: August 19, 2020 Online Published: August 27, 2020 doi:10.5539/mas.v14n9p28 URL: https://doi.org/10.5539/mas.v14n9p28 Abstract In our modern societies, One of the main and simplest signature traits is hot water as a convenient and efficient way of life either for industrial and domestic purposes, however, obtaining hot water in most cases will be through fossil fuel either by direct burning for the fuel for heating or indirectly by using electricity that generated by fossil fuel. Using solar heaters will limit the in some extent the usage of fossil fuel. A flat solar water heater of (165 to 175) cm 3 has been constructed to be used as a model for educational purposes. The solar heater is made of local materials consist of galvanized iron pipes, glass surfaces, wool insulation, aluminum frame, and fixed iron base. Moreover, Thermocouples, pyranometer, and an anemometer were used to test the performance of the heater in four days in May for the angle of inclination of the complex 320 is on the horizontal. In conclusion, the daily average efficiency was around 57%. The temperature in the tank is about 62 0 C at noon, which is sufficient for home use throughout the day. Keywords: solar heater, thermal, water, renewable energy 1. Introduction Energy has the biggest impact on any country's socio-economic growth. Therefore, due to economic and technological advances around the world, energy demand over the 2006–2030 forecast period will increase by a total of 44.2%(Mohamed & Lee, 2006). However, a significant proportion of the energy comes from fossil fuel, and it is well known that burning fossil fuels emit gaseous emissions, which are responsible for the effects of global warming and greenhouse gases. Those processes will result in global climate change, depletion of stratospheric ozone, loss of biodiversity; changes in hydrological systems and freshwater sources, land degradation and increase of stress on food-producing systems(Leo, 1996). Therefore, several countries around the world are using renewable energy to address environmental problems related to the use of fossil fuels, not just to generate electricity, but also to address environmental problems(Harikrishnan, Deepak, & Kalaiselvam, 2014). The use of renewable energy, particularly solar energy, is therefore very important in terms of harnessing environmentally friendly clean energy. In virtually all residential or industrial houses. whether, over the roof, there is space that can be used by installing solar energy systems such as solar water heaters, PV modules. Rooftop solar systems are today the exclusive, innovative and competitive solutions available on the market(Hu, Li, Gao, & Yin, 2014). Solar energy is likely to be one of the most promising sources of renewable energy over the next few decades, and in reality, it is particularly important in countries such as Spain, Germany, China, the USA, India, Malaysia, Bangladesh and some other countries that have abundant high solar intensity(A.Azouz, 2019b; Mohsen, Al-Ghandoor, & Al-Hinti, 2009; Sarhaddi, Farahat, Ajam, Behzadmehr, & Adeli, 2010). The solar energy applications can be divided into two categories: (1) Photovoltaic (PV) system, which converts solar energy into electrical energy. (2) The solar thermal system, which converts solar energy into thermal energy like a solar water heater.