Technical Journal of Engineering and Applied Sciences
Available online at www.tjeas.com
©2014 TJEAS Journal-2014-4-1/14-17
ISSN 2051-0853 ©2014 TJEAS
Hybrid Wind and Solar Electric Generation System
Ardashir Arash, Maghsud Nasiry, Samad Baghi and Sajjad Sadig
Department of Electrical Engineering, Ardabil Branch, Islamic Azad University, Ardabil, Iran
Correspondence author email: m.na30ri@yahoo.com
ABSTRACT: Renewable energy sources such as wind, solar, hydro power, biomass, geothermal
and ocean resources are considered for clean energy generation. Solar and wind energy are two of
the most viable renewable energy sources. Electricity energy generation by photovoltaics solar cells
and wind turbine increased rapidly in recent years. This paper presents operating both energy
sources wind and solar alongside one another in order to take advantage of their complementary
characters. In fact, the hybrid wind and solar Power system harnesses the energies in Sun and Wind
to electric generation. With this combination, the optimum utilization of resources and thus improves
the efficiency as compared with their individual generation mode can achieve. Also the hybrid Wind
and Solar system increases the reliability and reduces the dependence on one single source.
Key words: Wind energy, solar energy, wind turbines, photovoltaics cell, Hybrid power system
INTRODUCTION
Nowadays most of the energy demand is supplied by fossil fuels. Greenhouse gases and pollutants
increase when fossil fuels are converted into heat or electricity. Therefore atmosphere is damaged and global
warming developed. Fortunately, as the resources are limited, our dependence on fossil is close to its end.
Nowadays most of the research is about how to utilize the energy in a better way as well as research on the
use of renewable energy resources (Subraahmanyam, 2012).
Renewable energy sources such as wind and solar energy are clean, unlimited, and environmental
friendly. Such characteristics have caused that the energy sector to use renewable energy on a larger scale.
Solar charged battery systems provide power supply for complete a day regardless of bad weather (Arjun,
2013). To increase the efficiency of solar panels, solar panels are installed on a tracking system that follows the
position of the sun for to get a more light intensity so we can extract a large amount of power from solar
radiations. Wind energy is the kinetic energy associated with the movement of atmospheric air. Wind energy
systems convert this kinetic energy to more useful forms of power. Wind turbines transform the energy in the
wind into mechanical power, which can then be used directly for converting to electric power. Wind turbines can
be used singly or in clusters called ’wind farms.
However, the solar and wind energy have drawbacks. The one that is common to solar and wind
energy is their dependence on environmental factors such as weather and climatic conditions. Fortunately, due
to complementary nature of wind and energy, some of these problems can be removed by overcoming the
strengths of one with the weaknesses of the other. This brings us to the hybrid wind and solar power
generation concept (Kanase, 2010).
Hybrid Wind and Solar system have been installed to provide electricity to the billions of people that
do not have access to mains electricity. Power supply to remoter houses or villages, telecommunications,
irrigation and water supply are important application of Hybrid solar and wind energy system. In the last
decade, this energy system has shown its huge potential (Sivaramakrishna, 2013).
This paper presents the hybrid solar-wind power system that takes advantage of wind and solar
energy’s complementary characteristics to generate electrical energy.
HYBRID SOLAR WIND POWER SYSTEM BLOCK DIAGRAM
Hybrid Solar-Wind electric generation system is the combined electric generating system by solar
photovoltaics panel and wind mill. This hybrid system also includes a battery which is used to store the energy
generated from both energy converter. Using this system power generation by photovoltaics panel when
sunlight radiation is available and windmill when wind energy source is available can be achieved. As well as
both units can be generated electric power when both sources are available. By providing the battery
continuous power supply is possible when both sources are idle (Yang , 2009).
Tech J Engin & App Sci., 4 (1): 14-17, 2014
There are two working principle for hybrid energy generation: off-grid hybrid power and on-grid. The
working principle of an off-grid hybrid power system, also called stand-alone system, strongly deferent from grid
connected hybrid system. In this case, electric power is not fed into a grid, but is either stored in batteries or it
is locally consumed immediately. The functional block diagram of an off grid hybrid solar and wind energy
system shows in figure 1. The electric generated from wind mill is AC voltage which is converted through ACDC rectifier. The dc-dc converters are used to the regulation for solar system and wind mill (Dihrab , 2010).
Figure1. Hybrid solar and wind energy block diagram
COMPONENT OF THE HYBRID POWER SYSTEM
The wind and solar energy resource are unstable energy because the sun does not shine for the entire
day and the wind does not blow throughout the day and it is the most important reason to install a hybrid power
system. A hybrid power system converts the wind and sun energy to electric energy and during the day time
stored a battery can be a much more reliable and realistic power source (Bakos, 2003). The load can still be
supplied by the stored energy in the batteries even when there is no wind or sun. The hybrid system
components are as follows:
Photovoltaics Solar Panel
The photovoltaic panels directly convert the sunlight into electricity in solar cells. When solar cells are
exposed to sunlight, electrons excite from the valence band to the conduction band creating charged particles
called electron-hole carriers. By bringing P and N type semiconductor together, a p-n junction serves for
creating an electric field across the solar cells, which is able to separate holes and electrons and if the incident
photon is enough energy to dislodge a valance electron, the electron will jump to the conduction band and
initiate an electron coming out from the solar cells (Mostafa Tobnaghi, 2013). This process shows in Figure 2.
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Tech J Engin & App Sci., 4 (1): 14-17, 2014
Figure2. Solar cells working principle
Wind Power
Wind turbines are used to convert the wind power into electric power. Electric generator inside the
turbine converts the mechanical power into the electric power. Wind turbine systems are available ranging from
50W to 2-3 MW. The energy production by wind turbines depends on the wind velocity acting on the turbine. A
dc/dc converter is interfacing the generator with the dc bus. The converter commands the voltage on the
synchronous generator terminals, indirectly controlling the operation point of the wind turbine and,
consequently, its power generation (Yang, 2007).
Batteries
The batteries in the system provide to store the electricity that is generated from the wind or the solar
power. Any required capacity can be obtained by parallel or serial connections of the batteries. The battery that
provides the most advantageous operation in the wind and solar electric systems are maintenance free dry
type and utilizes the special electrolytes. These batteries provide a perfect performance for long discharges
(Elhadidy, 2004).
Inverter
Energy stored in the battery is drawn by electrical loads through the inverter, which converts DC
voltage into AC voltage. The inverter has in-built protection for Low Battery Voltage, Short-Circuit, Reverse
Polarity, and Over Load.
DESCRIPTION OF A MOBILE HYBRID POWER GENERATOR
Figure 3 shows a mobile hybrid electric generator. Electricity is generated from Solar, and Wind,
making the hybrid generator a clean and robust power source. Electricity is stored in batteries so the system
ready for use on demand 24 hours a day. The system derives most of its energy through the solar Photovoltaic
(PV) array [10]. The PV array supplies DC power to the inverter during the day and at the same time charges a
bank of batteries. The inverter converts the DC power into AC at 240/400 VAC, 50/60 Hz. At night time, the
batteries supply power to the inverter thereby providing reliable power 24 hours a day.
A mobile hybrid Solar and Wind power specifications are given below.
Solar PV Array Power: 4410 Watts, 22 kWh per day
Wind turbine/generator: 1 kW
Battery: 48 VDC, 1500 AH
Inverter Rating: 230VAC/50Hz, 1-ph or 3-ph, 6 kW
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Tech J Engin & App Sci., 4 (1): 14-17, 2014
Figure3. A mobile hybrid solar and wind power generator system
CONCLUSION
The hybrid Solar PV and Wind power generator system was explained. The hybrid generator range can
power a single home, farm house, factory, hospital or an entire village with much more cost effective solution to
supplying power compared to diesel generators. It reduces the dependence on one single source and has
increased the reliability. Hence we could improve the efficiency of the system as compared with their individual
mode of generation and Ready for use on demand 24 hours a day.
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