CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND TO THE STUDY
The use of renewable energy
increased greatly just after the first big oil crisis in the late seventies. At
that time, economic issues were the most important factors, hence interest in
such processes decreased when oil prices fell. The current resurgence of
interest in the use of renewable energy is driven by the need to reduce the
high environmental impact of fossil-based energy systems. Harvesting energy on
a large scale is undoubtedly one of the main challenges of our time. Future
energy sustainability depends heavily on how the capacity of renewable energy is
improved in the next few decades.
Although in most
power-generating systems, the main source of energy (the fuel) can be
manipulated, this is not true for solar and wind energies (Valenzuela, et al,
2004). The main problems with these energy sources are cost and availability,
wind and solar power are not always available where and when needed. Unlike
conventional sources of electric power, these renewable sources are not
“dispatchable”—the power output cannot be controlled. Daily and seasonal
effects and limited predictability result in intermittent generation. Some
manufacturers has released products to facilitate the integration of renewable
energy but the researcher is examining ways of improving the capacity of
renewable power system using solar power panel (Camacho et al, 2007).
Industry must overcome a number
of technical issues to deliver renewable energy in significant quantities.
Control is one of the key enabling technologies for the deployment of renewable
energy systems. Solar power requires effective use of advanced control
techniques. In addition, reliable electric supply cannot be achieved without
extensive use of control technologies at all levels.
Solar power plant exhibit
changing dynamics, nonlinearities, and uncertainties—challenges that require
advanced control strategies to solve effectively. The use of more efficient
control strategies would not only increase the performance of these systems,
but would increase the number of operational hours of solar and wind plants and
thus reduce the cost per kilowatt-hour (KWh) produced.
The
solar have tremendous potential for fulfilling the world’s energy needs (White
House, 2010).
One of the greatest scientific
and technological opportunities researchers are faced with is approaches to developing
efficient ways to collect, convert, store, and utilize solar energy at an
affordable cost. The solar power reaching the earth’s surface is about 86,000
TW. Covering 0.22% of our planet with solar collectors with an efficiency of 8%
would be enough to satisfy the current global power consumption. Estimates are
that an energy project utilizing concentrating solar power (CSP) technology
deployed over an area of approximately 160 x 160 km in the Southwest U.S. could
produce enough power for the entire U.S. consumption.
Solar-sourced electricity can
be generated either directly using photovoltaic (PV) cells or indirectly by
collecting and concentrating the solar power to produce steam, which is then
used to drive a turbine to provide the electric power (CSP).
Concentrating solar thermal
systems use optical devices (usually mirrors) and sun-tracking systems to
concentrate a large area of sunlight onto a smaller receiving area. The
concentrated solar energy is then used as a heat source for a conventional
power plant. A wide range of concentrating technologies exists, the main ones
being parabolic troughs, solar dishes, linear Fresnel reflectors, and solar
power towers. The primary purpose of concentrating solar energy is to produce
high temperatures and therefore high thermodynamic efficiencies.
Parabolic trough systems are
the most commonly used CSP technology. A parabolic trough consists of a linear
parabolic mirror that reflects and concentrates the received solar energy onto
a tube (receiver) positioned along the focal line. The heat transfer fluid is
pumped through the receiver tube and picks up the heat transferred through the
receiver tube walls. The parabolic mirror follows the sun by tracking along a
single axis. Linear Fresnel reflectors use various thin mirror strips to
concentrate sunlight onto tubes containing heat transfer fluid. Higher
concentration can be obtained, and the mirrors are cheaper than parabolic
mirrors, but a more complex tracking mechanism is needed.
1.2 STATEMENT OF THE PROBLEM
The uncertainty and
intermittency of solar generation are major complications that must be
addressed before the full potential of this renewable power system can be
reached. The researcher provides an
overview of a solar power panel with an evolution of electricity
networks toward greater reliance on communications, computation, and control
which is a way aimed at improving it.
The
application of advanced digital technologies (i.e., microprocessor-based
measurement and control, communications, computing, and information systems)
which are expected to greatly improve the reliability, security,
interoperability, and efficiency of the electrical grid, while reducing
environmental impacts and promoting economic growth will be considered.
1.3 OBJECTIVES OF THE STUDY
The
following are the objectives of this study:
1.
To provide an overview on renewable
power system and its capacity.
2.
To examine ways of improving the
capacity of renewable power system using the solar power panel.
3.
To identify the limitations of solar
power system
1.4 RESEARCH QUESTIONS
1.
What is renewable power system and its
capacity?
2.
What are the ways of improving the
capacity of renewable power system using the solar power panel?
3.
What are the limitations of solar
power system?
1.6 SIGNIFICANCE OF THE STUDY
The
following are the significance of this study:
1.
Findings from this study will educate
students on renewable power system with emphasis on solar power system.
2.
It will educate researchers on methods
of improving the existing solar power technology.
3.
This research will also serve as a
resource base to other scholars and researchers interested in carrying out
further research in this field subsequently, if applied will go to an extent to
provide new explanation to the topic.
1.7 SCOPE/LIMITATIONS OF THE STUDY
This study will cover
approaches at improving the existing solar power technology with a view of
optimizing the operation of the system and minimizing environmental impacts.
LIMITATION OF STUDY
1. Financial
constraint-
Insufficient fund tends to impede the efficiency of the researcher in sourcing
for the relevant materials, literature or information and in the process of
data collection (internet, questionnaire and interview).
2. Time
constraint- The
researcher will simultaneously engage in this study with other academic work.
This consequently will cut down on the time devoted for the research work.
REFERENCES
E.F.
Camacho, F. Rubio, M. Berenguel, and L. Valenzuela. “A survey on control
schemes for distributed solar collector fields (part 1 and 2),” Solar
Energy, vol. 81, pp. 1240-1272, 2007
L.
Valenzuela, E. Zarza, M. Berenguel, and E.F. Camacho. “Direct steam generation
in solar boilers,” IEEE Control Systems Magazine, vol. 24, no. 2, pp.
15-29, 2004.
White
House. Weekly address [Online], July 3, 2010. Available at,
http://www.whitehouse.gov/blog/ 2010/07/03/weekly-address-a-solar-recovery#.