Abstract: Global Solar Radiation (H) for Dubai and Sharjah,
Latitude 25.25oN, Longitude 55oE and 25.29oN, Longitude 55oE
respectively have been studied using sunshine hour data (n) of the
areas using various methods. These calculated global solar radiation
values are then compared to the measured values presented by
NASA. Furthermore, the extraterrestrial (H0), diffuse (Hd) and beam
radiation (Hb) are also calculated. The diffuse radiation is calculated
using methods proposed by Page and Liu and Jordan (L-J). Diffuse
Radiation from the Page method is higher than the L-J method.
Moreover, the clearness index (KT) signifies a clear sky almost all
year round. Rainy days are hardly a few in a year and limited in the
months December to March. The temperature remains between 25oC
in winter to 44oC in summer and is desirable for thermal applications
of solar energy. From the estimated results, it appears that solar
radiation can be utilized very efficiently throughout the year for
photovoltaic and thermal applications.
Abstract: Solar energy has a major role in renewable energy
resources. Solar Cell as a basement of solar system has attracted lots
of research. To conduct a study about solar energy system, an
authenticated model is required. Diode base PV models are widely
used by researchers. These models are classified based on the number
of diodes used in them. Single and two-diode models are well
studied. Single-diode models may have two, three or four elements.
In this study, these solar cell models are examined and the simulation
results are compared to each other. All PV models are re-designed in
the Matlab/Simulink software and they examined by certain test
conditions and parameters. This paper provides comparative studies
of these models and it tries to compare the simulation results with
manufacturer-s data sheet to investigate model validity and accuracy.
The results show a four- element single-diode model is accurate and
has moderate complexity in contrast to the two-diode model with
higher complexity and accuracy
Abstract: ZnO heteronanostructured nanowires arrays have
been fabricated by low temperature solution method. Various
heterostructures were synthesized including CdS/ZnO,
CdSe/CdS/ZnO nanowires and Co3O4/ZnO, ZnO/SiC
nanowires. These multifunctional heterostructure nanowires
showed important applications in photocatalysts, sensors,
wettability control and solar energy conversion.
Abstract: Beam and diffuse radiation data are extracted analytically from previous measured data on a horizontal surface in Zarqa city. Moreover, radiation data on a tilted surfaces with different slopes have been derived and analyzed. These data are consisting of of beam contribution, diffuse contribution, and ground reflected contribution radiation. Hourly radiation data for horizontal surface possess the highest radiation values on June, and then the values decay as the slope increases and the sharp decreasing happened for vertical surface. The beam radiation on a horizontal surface owns the highest values comparing to diffuse radiation for all days of June. The total daily radiation on the tilted surface decreases with slopes. The beam radiation data also decays with slopes especially for vertical surface. Diffuse radiation slightly decreases with slopes with sharp decreases for vertical surface. The groundreflected radiation grows with slopes especially for vertical surface. It-s clear that in June the highest harvesting of solar energy occurred for horizontal surface, then the harvesting decreases as the slope increases.
Abstract: The intermittent nature of solar energy and the energy
requirements of buildings necessitate the storage of thermal energy.
In this paper a hybrid system of storing solar energy has been
analyzed. Adding a LHS medium to a commercial solar water heater,
the required energy for heating a small room was obtained in
addition to preparing hot water. In other words, the suggested hybrid
storage system consists of two tanks: a water tank as a SHS medium;
and a paraffin tank as a LHS medium. A computing program was
used to find the optimized time schedule of charging the storage
tanks during each day, according to the solar radiation conditions.
The results show that the use of such system can improve the
capability of energy gathering comparing to the individual water
storage tank during the cold months of the year. Of course, because
of the solar radiation angles and shorten daylight in December &
January, the performance will be the same as the simple solar water
heaters (in the northern hemisphere). But the extra energy stored in
November, February, March & April, can be useful for heating a
small room for 3 hours during the cold days.
Abstract: The paper aims to show that implementing different
types of reflectors in solar energy systems, will dramatically improve
energy production by means of concentrating and intensifying more
sunlight onto a solar cell. The Solar Intensifier unit is designed to
increase efficiency and performance of a set of solar panels. The unit
was fabricated and tested. The experimental results show good
improvement in the performance of the solar energy system.
Abstract: This paper presents the modeling results of an
innovative system for the temperature control in the interior
compartment of a stationary automobile facing the solar energy from
the sun. A very thin layer of PCM inside a pouch placed in the
ceiling of the car in which the heating energy is absorbed and release
with melting and solidification of phase change materials. As a result
the temperature of the car interior is maintained in the comfort
condition. The amount of required PCM has been calculated to be
about 755 g. The PCM-temperature controlling system is simple and
has a potential to be implemented as a practical solution to prevent
undesirable heating of the automobile-s cabin.
Abstract: Heat powered solid sorption is a feasible alternative to
electrical vapor compression refrigeration systems. In this paper,
activated carbon (powder type Maxsorb and fiber type ACF-A10)-
CO2 based adsorption cooling cycles are studied using the pressuretemperature-
concentration (P-T-W) diagram. The specific cooling
effect (SCE) and the coefficient of performance (COP) of these two
cooling systems are simulated for the driving heat source
temperatures ranging from 30 ºC to 90 ºC in terms of different
cooling load temperatures with a cooling source temperature of 25
ºC. It is found from the present analysis that Maxsorb-CO2 couple
shows higher cooling capacity and COP. The maximum COPs of
Maxsorb-CO2 and ACF(A10)-CO2 based cooling systems are found
to be 0.15 and 0.083, respectively. The main innovative feature of
this cooling cycle is the ability to utilize low temperature waste heat
or solar energy using CO2 as the refrigerant, which is one of the best
alternative for applications where flammability and toxicity are not
allowed.
Abstract: The world demand for potable water is
increasing every day with growing population. Desalination
using solar energy is suitable for potable water production
from brackish and seawater. In this paper, we present a
theoretical study of solar distillation in a single basin under
the open environmental conditions of Chabahar-Iran. The still
has a base area of 2000mm×500mm with a glass cover
inclined at 25° in order to obtain extra solar energy. We model
the still and conduct its energy balance equations under minor
assumptions. We computed the temperatures of glass cover,
seawater interface, moist air and bottom using numerical
method. The investigation addressed the following: The still
productivity, distilled water salinity and still performance in
terms of the still efficiency. Calculated still productivity in
July was higher than December. So in this paper, we show
that still productivity is directly functioning of solar radiation.