International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Solar energy has a great potential in Albania. The use of hybrid photovoltaic – thermal (PV/T) systems has shown an impressive progress in recent years. PV/T system can produce electricity and thermal energy simultaneously. In this paper, a 200 W PV/T system is introduced using water as cooling fluid, in order to regulate the temperature increase of the photovoltaic panels. The heat is collected via working fluid in a water tank. This study analyses the energy generation of this experimental setup, and aims to provide some accurate information in future developments and implementation of this technology in Albania. Coupling of PV/T system with heat pumps in buildings to meet the energy requirements could be of great interest for Albania’s energy consumers

Photovoltaic thermal system (PV-T) converts sunlight into electricity and heat simultaneously. The overall efficiency of these systems is higher than the efficiencies of PV panels and solar collectors together. In Albania energy production from photovoltaic systems has been promoted in the recent years. Albania’s Mediterranean climate conditions are very favourable for investment in renewable energy systems. In this study a stand-alone 280 W PV-T panel is considered with respect to thermal analysis of the system. The panel is installed at the terrace of the building University in Tirana, Albania. The aim of this work is to present the temperature profile of the panel, since there is a correlation between efficiency and temperature. In order to analyse the temperature distribution on the panel surface a series of experiments are carried out. Temperature variation vs. time for different water flow rate was performed. The inlet and outlet water temperature profile is drawn in this article.

Drilling is most often associated with hole-making. The surface roughness parameters represent a measure of surface quality, and it is mainly influenced by the cutting process parameters (cutting speed, feed rate, drill diameter), tool geometry, tool material, tool type, type of processing, coolant and lubricating fluid, tool machine and type of work piece material.

The purpose of this paper is to explore the effects of drilling parameters such as; cutting speed (vc), feed rate (f), drill diameter (d) and drill point angle (θ) on the surface roughness. There are different parameters used to estimate the severity of the surface roughness (Ra, Rz, Rq and Rt). The arithmetic average deviation Ra is commonly used for finish surface processing. The experimental plan was based on Box –Wilson Central Composite Design. First order model predicting equations for surface roughness have been established by using RSM methodology to collecting the experimental data, during machining of Ck45E steel according to EN 10083-1.1191 in wet drilling process, using HSS coated TiN drill tools.