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 withan 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#.