Environmental Engineering Reference
In-Depth Information
Physics of solar energy and
its applications
Napoleon Enteria
1
&Aliakbar Akbarzadeh
2
1
Enteria Grün Energietechnik, Davao, Philippines
2
School of Aerospace, Manufacturing and Mechanical Engineering,
RMIT University, Melbourne, Australia
1.1 INTRODUCTION
Solar energy has existed for millions of years and has been used by many non-living
and living things for physical, chemical and biological changes and processes. For
generation after generation, solar energy has been the main source of daily energy in
many ways. The start of human modernity and civilization changed the utilization
of solar energy. Previous human civilizations utilized solar energy for lighting, food
drying and personal care. Modern humans utilize solar energy for everyday existence,
work purposes and generally for living. As human demand for modern energy supply
increases, attention to solar energy becomes more intense.
Because of the increasing population, demand for better comfort, urbanization and
industrialization, the pressure on conventional energy sources is increasing. The rapid
increase of energy demand rattles the chain of energy supply which has difficulty in
meeting the rapid rise in energy demand. This rapid demand not only makes the world
more volatile in terms of energy politics but also accentuates the environmental hazards
associated with emission of greenhouse gases, particularly from chemical processes
involved in utilizing the thermal energy obtained from conventional energy sources.
Consequently there are active plans to utilize solar energy for different processes to
minimize energy demand from conventional energy supply sources.
Conventional energy supplies are based on fossil fuel or carbon-based energy
sources, based on the liberation of stored energy through combustion. Through com-
bustion processes or chemical processes, thermal energy is generated. At the same time,
radiant energy or solar energy is an available energy which can be used as replacement
for the energy liberated/generated during combustion processes. Therefore, several
methods, concepts and ideas are being pursued to maximize the utilization of solar
energy as an alternative form of energy to minimize the usage of carbon-based energy
sources. This chapter introduces the concept of solar energy and its applications as
alternatives for conventional energy supply and demand.
1.2 SOLAR ENERGY AND ENERGY DEMAND
The Sun is the nearest and only star around which the Earth and other planets are
constantly rotating. The energy generated by the Sun is utilized on Earth for the support
of living organisms. As the Sun is radiating and transmitting energy in the form of
