THEORETICAL ANALYSIS OF WATER COOLED PHOTOVOLTAIC THERMAL PANELS

Abstract

The sustainability and the efficient capitalization of the solar energy are studied for a system that incorporates two different subsystems: photovoltaic panels (electricity production) and their cooling (heat production). This complex system ensures the production of electricity and thermal energy in order to satisfy the need for electricity and heating of the buildings. The two types of energy are quantitatively dependent on each other and, therefore, they must be managed in such a way that the production of either of them does not fall into the detriment of the other. In other words, the maximum efficiency is reached at the intersection of the two curves of electricity and heat production and the instrument that manages the two types of energy is the photovoltaic thermal panel. The photovoltaic thermal panels, especially if they are integrated into the buildings, are able to bring an important contribution to the concept of nearly Zero Energy Building (nZEB). The amount of heat resulting from the cooling of the panels can be utilized for preheating domestic hot water, space heating or other usage in the buildings. The article presents the theoretical and analytical model that can be used to analyse the cooling of photovoltaic panels by means of a water-based system. This theoretical model was implemented in a module dedicated to the cooling of photovoltaic thermal panels, in the Cool-PV computer application developed by researchers at the Faculty of Civil Engineering and Building Services in Iasi, Romania. In conclusion, the constructive variant that presents maximum efficiency, in according with input and output data (heat gained from PV/T panel) is represented by 22mm Cu diameter cooling PV/T system, on 250mm M40 concrete think. As a result of the theoretical analysis, will be materialize in a experimental set-up, using a monitoring system of the panel temperature and control solution in order to optimize the energy consumption is presented. The analysis is also aiming at determining the optimal time for using the cooling system and the calculation of the amount of heat resulted.