Large-scale solar water heating systems analysis in Ethiopia: a case study

Abstract

Ethiopia is proximate to the Equator and receives adequate sunshine throughout the year, but the effective use of solar energy for large-scale applications is not yet adapted. This paper investigates the possible use of solar energy for large-scale water heating systems on the selected potential sites in the country. Global and diffuse radiations over the collector surfaces for all the selected sites are predicted from sunshine duration using numerical equations, and the transient analysis of the system is performed using a single glass cover flat plate collector solar water heater with riser and header type active system for a hot water supply temperature of 50 • C. The total number of collectors, the size and number of storage tanks required and hot water temperature in the storage tank at each hour of a day and month of a year are also determined.

Long-Term Performance Analysis of Direct Photovoltaic Thermal-Assisted Heat Pump Water Heater Using Computational Model

“…(3) Absorber Plate. The difference between the heat transferred to the absorber from the PV module and the sum of heat transferred from the absorber to the water in the tubes and the ambient through the back of insulation results in the rate of change of energy stored in the absorber [25].…”

Review on Solar Assisted Heat Pump Water Heating System

“…The maximum HT coefficient is observed when the mass flow rate is high and temperature of collector is low and HT coefficient reaches to its summit value at the maximum solar radiation strength. Flat plate collector plays the major role on the solar water heating system [55] .Hasim et al, 2018 [56] studied about the FPSC and concluded that the 0.0883 L/Sec flow rate heat up the water till 51.4℃ and 0.1085 L/Sec flow rate heat up the water till 49℃. Hernandez and Guzman, 2016 [57] studied about the 3 water heating system which are two plane system and one vacuum tube heater, the difference between the collector of the copper tube and stainless steel tube has maximum efficiency of 76.31% and 71.58% respectively and for the vacuum tube the maximum efficiency of 72.33%.…”

Archives of Electrical Engineering

“…if 1000 < Re air < 5000 Nu air = 0.3 + 0.54 Re 0.6 air . The dimensionless Reynolds number of the air over the outer wall of the glass covers is [19,23]:…”

“…The effective temperature of the sky has been calculated from the following simple empirical relation [11,19,23]:…”

“…The difference between the absorbed solar radiation and the thermal loss is useful energy that is given by [23,24]:…”