OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
STUDY OF SOLAR WATER HEATERS BASED ON EXERGY ANALYSIS
Dilip Johari 1 , Ashok Yadav 2 , Ravi Verma 3
1
M.Tech Student, 2 Asst. Prof., Department of Mechanical Engineering, Dayalbagh Educational University,
Agra, U.P., India
3 Asst. Prof., Department of Mechanical Engineering, Graphic Era University, Dehradun, Uttrakhand, India
Email: 1 dilipjohari@gmail.com, 2 ashokyadavaca@gmail.com, 3 raviverma2020@gmail.com
Abstract
Energy application from the sun to heat water is well known. Solar water heater is a device which is used for
heating the water for domestic and industrial purposes by utilizing the solar energy. Solar energy is the energy
which is coming from sun in the form of solar radiations in infinite amount, when these solar radiations falls on
absorbing surface, then they gets converted into the heat, this heat is used for heating the water.This paper presents
the study based on three procedure theory. Exergy analysis is conducted with the aim of providing some methods to
save cost and keep the efficiency of solar water heater to desired extent and at the same time figuring out related
exergy losses. In the Exergy analysis of solar water heater systems, the conversion of solar radiation is typically
included within the analysis. Exergy analysis has been widely used for the optimisation and allocation of losses in
energy systems. Exergy is the expression for loss of available energy due to the creation of entropy in irreversible
systems or processes. The exergy loss in a system or component is determined by multiplying the absolute
temperature of the surroundings by the entropy increase. Exergy is also a measure of the maximum useful work that
can be done by a system interacting with an environment. It has been widely used in the design, simulation and
performance evaluation of energy systems.
Keywords: Solar water heater, Laws of Thermodynamics, Exergy Analysis, Three procedure theory
1. Introduction
The solar energy is the most capable of the alternative energy sources. Despite the characteristic of low density and
unsteady in nature, the research of solar energy has received significant attention in recent years. Due to increasing
demand for energy and rising cost of fossil type fuels (i.e., gas or oil) solar energy is considered an attractive source
of renewable energy that can be used for water hearing in both homes and industry. Heating water consumes nearly
20% of total energy consumption for an average family. Solar water heating systems are the cheapest and most
easily affordable clean energy available to homeowners that may provide most of hot water required by a family.
Solar heater is a device which is used for heating the water, for producing the steam for domestic and industrial
purposes by utilizing the solar energy. Solar energy is the energy which is coming from sun in the form of solar
radiations in infinite amount, when these solar radiations falls on absorbing surface, then they gets converted into the
heat, this heat is used for heating the water. This type of thermal collector suffers from heat losses due to radiation
and convection. Such losses increase rapidly as the temperature of the working fluid increases.
Exergy is a measure of the maximum useful work that can be done by a system interacting with an environment
which is at a constant pressure and temperature. Exergy is the expression for loss of available energy due to the
creation of entropy in irreversible processes. The analysis is based on the three procedure theory given by Professor
Hua Ben. The three different procedures of this theory are: Conversion procedure, utilization procedure, and
recycling procedure.
2. Problem Statement
In today’s modern world, where new technologies are introduced every day, the use of non renewable energy is
increasing quickly particularly petroleum fuel. Quickly depleting reserve of petroleum and decreasing air quality
raise question about the future. The fact that non renewable energy resources will be available at the present usage
level only for a limited period has been accepted worldwide. As a consequence, the need for renewable energy
resources becomes very urgent. As an absolutely clean energy, solar energy is of most importance and has been
most emphasized on so far.
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