Abstract: This paper presents a grid synchronization technique based on adaptive notch filter for SPV (Solar Photovoltaic) system along with MPPT (Maximum Power Point Tracking) techniques. An efficient grid synchronization technique offers proficient detection of various components of grid signal like phase and frequency. It also acts as a barrier for harmonics and other disturbances in grid signal. A reference phase signal synchronized with the grid voltage is provided by the grid synchronization technique to standardize the system with grid codes and power quality standards. Hence, grid synchronization unit plays important role for grid connected SPV systems. As the output of the PV array is fluctuating in nature with the meteorological parameters like irradiance, temperature, wind etc. In order to maintain a constant DC voltage at VSC (Voltage Source Converter) input, MPPT control is required to track the maximum power point from PV array. In this work, a variable step size P & O (Perturb and Observe) MPPT technique with DC/DC boost converter has been used at first stage of the system. This algorithm divides the dPpv/dVpv curve of PV panel into three separate zones i.e. zone 0, zone 1 and zone 2. A fine value of tracking step size is used in zone 0 while zone 1 and zone 2 requires a large value of step size in order to obtain a high tracking speed. Further, adaptive notch filter based control technique is proposed for VSC in PV generation system. Adaptive notch filter (ANF) approach is used to synchronize the interfaced PV system with grid to maintain the amplitude, phase and frequency parameters as well as power quality improvement. This technique offers the compensation of harmonics current and reactive power with both linear and nonlinear loads. To maintain constant DC link voltage a PI controller is also implemented and presented in this paper. The complete system has been designed, developed and simulated using SimPower System and Simulink toolbox of MATLAB. The performance analysis of three phase grid connected solar photovoltaic system has been carried out on the basis of various parameters like PV output power, PV voltage, PV current, DC link voltage, PCC (Point of Common Coupling) voltage, grid voltage, grid current, voltage source converter current, power supplied by the voltage source converter etc. The results obtained from the proposed system are found satisfactory.
Abstract: This paper presents the results of a Finite Element
based vibration analysis of a solar powered Unmanned Aerial
Vehicle (UAV). The purpose of this paper was to quantify the free
vibration, forced vibration response due to differing point inputs in
order to predict the relative response magnitudes and frequencies at
various wing locations of vibration induced power generators
(magnet in coil) excited by gust and/or control surface pulse-decays
used to help power the flight of the electric UAV. A Fluid Structure
Interaction (FSI) study was performed in order to ascertain pertinent
design stresses and deflections as well as aerodynamic parameters of
the UAV airfoil. The 10 ft span airfoil is modeled using Mylar as the
primary material. Results show that the free mode in bending is 4.8
Hz while the first forced bending mode is on range of 16.2 to 16.7 Hz
depending on the location of excitation. The free torsional bending
mode is 28.3 Hz, and the first forced torsional mode is range of 26.4
to 27.8 Hz, depending on the location of excitation. The FSI results
predict the coefficients of aerodynamic drag and lift of 0.0052 and
0.077, respectively, which matches hand-calculations used to validate
the Finite Element based results. FSI based maximum von Mises
stresses and deflections were found to be 0.282 MPa and 3.4 mm,
respectively. Dynamic pressures on the airfoil range from 1.04 to
1.23 kPa corresponding to velocity magnitudes in range of 22 to 66
m/s.
Abstract: In most existing buildings in hot climate, cooling
loads lead to high primary energy consumption and consequently
high CO2 emissions. These can be substantially decreased with
integrated renewable energy systems. Kuwait is characterized by its
dry hot long summer and short warm winter. Kuwait receives annual
total radiation more than 5280 MJ/m2 with approximately 3347 h of
sunshine. Solar energy systems consist of PV modules and parabolic
trough collectors are considered to satisfy electricity consumption,
domestic water heating, and cooling loads of an existing building.
This paper presents the results of an extensive program of energy
conservation and energy generation using integrated photovoltaic
(PV) modules and Parabolic Trough Collectors (PTC). The program
conducted on an existing institutional building intending to convert it
into a Net-Zero Energy Building (NZEB) or near net Zero Energy
Building (nNZEB). The program consists of two phases; the first
phase is concerned with energy auditing and energy conservation
measures at minimum cost and the second phase considers the
installation of photovoltaic modules and parabolic trough collectors.
The 2-storey building under consideration is the Applied Sciences
Department at the College of Technological Studies, Kuwait. Single
effect lithium bromide water absorption chillers are implemented to
provide air conditioning load to the building. A numerical model is
developed to evaluate the performance of parabolic trough collectors
in Kuwait climate. Transient simulation program (TRNSYS) is
adapted to simulate the performance of different solar system
components. In addition, a numerical model is developed to assess
the environmental impacts of building integrated renewable energy
systems. Results indicate that efficient energy conservation can play
an important role in converting the existing buildings into NZEBs as
it saves a significant portion of annual energy consumption of the
building. The first phase results in an energy conservation of about
28% of the building consumption. In the second phase, the integrated
PV completely covers the lighting and equipment loads of the
building. On the other hand, parabolic trough collectors of optimum
area of 765 m2 can satisfy a significant portion of the cooling load,
i.e about73% of the total building cooling load. The annual avoided
CO2 emission is evaluated at the optimum conditions to assess the
environmental impacts of renewable energy systems. The total annual
avoided CO2 emission is about 680 metric ton/year which confirms
the environmental impacts of these systems in Kuwait.
Abstract: In an attempt to investigate the performance of single
basin solar still for climate conditions of Ludhiana a single basin
solar still was designed, fabricated and tested. The energy balance
equations for various parts of the still are solved by Gauss-Seidel
iteration method. Computer model was made and experimentally
validated. The validated computer model was used to estimate the
annual distillation yield and performance ratio of the still for
Ludhiana. The Theoretical and experimental distillation yield were
4318.79 ml and 3850 ml respectively for the typical day. The
predicted distillation yield was 12.5% higher than the experimental
yield. The annual distillation yield per square metre aperture area and
annual performance ratio for single basin solar still is 1095 litres and
0.43 respectively. The payback period for micro-stepped solar still is
2.5 years.
Abstract: A solar dish collector has been designed, fabricated
and tested for its performance on 10-03-2015 in Salem, Tamilnadu,
India. The experiments on cooking vessels of coated and un-coated
with 5 Liters capacity have been used for cooking Rice. The results
are shown in graphs. The solar cooker is always capable of cooking
food within the expected length of time and based on the solar
radiation levels. With minimum cooking power, the coated pressure
cooker of 5 Liters capacity cooks the food at faster manner. This is
due to the conductivity of the coating material provided in the cooker.
Abstract: Currently, green rating systems are mainly utilized for
correctly sizing mechanical and electrical systems, which have short
lifetime expectancies. In these systems, passive solar and bio-climatic
architecture, which have long lifetime expectancies, are neglected.
Urban rating systems consider buildings and services in addition to
neighborhoods and public transportation as integral parts of the built
environment. The main goal of this study was to develop a more
consistent point allocation system for urban building standards by
using six different lifetime shearing layers: Site, Structure, Skin,
Services, Space, and Stuff, each reflecting distinct environmental
damages. This shearing-layer concept was applied to internationally
well-known rating systems: Leadership in Energy and Environmental
Design (LEED) for Neighborhood Development, BRE
Environmental Assessment Method (BREEAM) for Communities
and Comprehensive Assessment System for Building Environmental
Efficiency (CASBEE) for Urban Development. The results showed
that LEED for Neighborhood Development and BREEAM for
Communities focused on long-lifetime-expectancy building designs,
whereas CASBEE for Urban Development gave equal importance to
the Building and Service Layers. Moreover, although this rating
system was applied using a building-scale assessment, “Urban Area +
Buildings” focuses on a short-lifetime-expectancy system design,
neglecting to improve the architectural design by considering bioclimatic
and passive solar aspects.
Abstract: Transparent nickel doped cobalt sulfide was fabricated
on a SnO2:F electrode and tested as an efficient electrocatalyst and as
an alternative to the expensive platinum counter electrode. In order to
investigate how this electrode could affect the electrical
characteristics of a dye-sensitized solar cell, we manufactured cells
with the same TiO2 photoanode sensitized with dye (N719) and
employing the same quasi-solid electrolyte, altering only the counter
electrode used. The cells were electrically and electrochemically
characterized and it was observed that the ones with the Ni doped
CoS2 outperformed the efficiency of the cells with the Pt counter
electrode (3.76% and 3.44% respectively). Particularly, the higher
efficiency of the cells with the Ni doped CoS2 counter electrode (CE)
is mainly because of the enhanced photocurrent density which is
attributed to the enhanced electrocatalytic ability of the CE and the
low charge transfer resistance at the CE/electrolyte interface.
Abstract: Nanotechnology has become the world attention in
various applications including the solar cells devices due to the
uniqueness and benefits of achieving low cost and better
performances of devices. Recently, thin film solar cells such as
Cadmium Telluride (CdTe), Copper-Indium-Gallium-diSelenide
(CIGS), Copper-Zinc-Tin-Sulphide (CZTS), and Dye-Sensitized
Solar Cells (DSSC) enhanced by nanotechnology have attracted
much attention. Thus, a compilation of nanotechnology devices
giving the progress in the solar cells has been presented. It is much
related to nanoparticles or nanocrystallines, carbon nanotubes, and
nanowires or nanorods structures.
Abstract: Greenhouses offer us suitable conditions which can
be controlled easily for the growth of the plant and they are made by
using a covering material that allows the sun light entering into the
system. Covering material can be glass, fiber glass, plastic or another
transparent element. This study investigates the solar energy usability
rates and solar energy benefitting rates of a semi-spherical (modified
arch) type greenhouse system according to different orientations and
positions which exists under climatic conditions of Bayburt. In the
concept of this study it is tried to determine the best direction and
best sizes of a semi-spherical greenhouse to get best solar benefit
from the sun. To achieve this aim a modeling study is made by using
MATLAB. However, this modeling study is run for some determined
shapes and greenhouses it can be used for different shaped
greenhouses or buildings. The basic parameters are determined as
greenhouse azimuth angle, the rate of size of long edge to short and
seasonal solar energy gaining of greenhouse. The optimum azimuth
angles of 400, 300, 250, 200, 150, 100, 50 m2 modified arch
greenhouse are 90o, 90o, 35o, 35o, 34o, 33o and 22o while their
optimum k values (ratio of length to width) are 10, 10, 10, 10, 6, 4
and 4 respectively. Positioning the buildings in order to get more
solar heat energy in winter and less in summer brings out energy and
money savings and increases the comfort.
Abstract: Remote arid areas of the vast expanses of the African
deserts hold huge subterranean reserves of brackish water resources
waiting for economic development. This work presents design
guidelines as well as initial performance data of new autonomous
solar desalination equipment which could help local communities
produce their own fresh water using solar energy only and, why not,
contribute to transforming desert lands into lush gardens. The output
of solar distillation equipments are typically low and in the range of 3
l/m2/day on the average. This new design with an integrated, water
based, environmentally-friendly solar heat storage system produced 5
l/m2/day in early spring weather. Equipment output during summer
exceeded 9 liters per m2 per day.
Abstract: The use of hydroelectric pump-storage system at large
scale, MW-size systems, is already widespread around the world.
Designed for large scale applications, pump-storage station can be
scaled-down for small, remote residential applications. Given the cost
and complexity associated with installing a substation further than
100 miles from the main transmission lines, a remote, independent
and self-sufficient system is by far the most feasible solution. This
article is aiming at the design of wind and solar power generating
system, by means of pumped-storage to replace the wind and /or solar
power systems with a battery bank energy storage. Wind and solar
pumped-storage power generating system can reduce the cost of
power generation system, according to the user's electricity load and
resource condition and also can ensure system reliability of power
supply. Wind and solar pumped-storage power generation system is
well suited for remote residential applications with intermittent wind
and/or solar energy. This type of power systems, installed in these
locations, could be a very good alternative, with economic benefits
and positive social effects. The advantage of pumped storage power
system, where wind power regulation is calculated, shows that a
significant smoothing of the produced power is obtained, resulting in
a power-on-demand system’s capability, concomitant to extra
economic benefits.
Abstract: This study examines the feasibility of indirect solar
desalination in oil producing countries in the Middle East and North
Africa (MENA) region. It relies on value engineering (VE) and costbenefit
with sensitivity analyses to identify optimal coupling
configurations of desalination and solar energy technologies. A
comparative return on investment was assessed as a function of water
costs for varied plant capacities (25,000 to 75,000 m3/day), project
lifetimes (15 to 25 years), and discount rates (5 to 15%) taking into
consideration water and energy subsidies, land cost as well as
environmental externalities in the form of carbon credit related to
greenhouse gas (GHG) emissions reduction. The results showed
reverse osmosis (RO) coupled with photovoltaic technologies (PVs)
as the most promising configuration, robust across different prices for
Brent oil, discount rates, as well as different project lifetimes.
Environmental externalities and subsidies analysis revealed that a
16% reduction in existing subsidy on water tariffs would ensure
economic viability. Additionally, while land costs affect investment
attractiveness, the viability of RO coupled with PV remains possible
for a land purchase cost
Abstract: A compound parabolic concentrator (CPC) is a wellknown
non-imaging concentrator that will concentrate the solar
radiation onto receiver (PV cell). One of disadvantage of CPC is has
tall and narrow height compared to its diameter entry aperture area.
Therefore, for economic reason, a truncation had been done by
removed from the top of the full height CPC. This also will lead to
the decreases of concentration ratio but it will be negligible. In this
paper, the flux distribution of untruncated and truncated 2-D hollow
compound parabolic trough concentrator (hCPTC) design is
presented. The untruncated design has initial height H=193.4mm
with concentration ratio C_(2-D)=4. This paper presents the optical
simulation of compound parabolic trough concentrator using raytracing
software TracePro. Results showed that, after the truncation,
the height of CPC reduced 45% from initial height with the
geometrical concentration ratio only decrease 10%. Thus, the cost of
reflector and material dielectric usage can be saved especially at
manufacturing site.
Abstract: Toddy sediment (TS) was cultured in a PDA medium
to determine initial yeast load, and also it was undergone sun, shade,
solar, dehumidified cold air (DCA) and hot air oven (at 400, 500 and
60oC) drying with a view to preserve viability of yeast. Thereafter,
this study was conducted according to two factor factorial design in
order to determine best preservation method. Therein the dried TS
from the best drying method was taken and divided into two portions.
One portion was mixed with 3: 7 ratio of TS: rice flour and the
mixture was divided in to two again. While one portion was kept
under in house condition the other was in a refrigerator. Same
procedure was followed to the rest portion of TS too but it was at the
same ratio of corn flour. All treatments were vacuum packed in triple
laminate pouches and the best preservation method was determined
in terms of leavening index (LI). The TS obtained from the best
preservation method was used to make foods (bread and hopper) and
organoleptic properties of it were evaluated against same of ordinary
foods using sensory panel with a five point hedonic scale.
Results revealed that yeast load or fresh TS was 58×106 CFU/g.
The best drying method in preserving viability of yeast was DCA
because LI of this treatment (96%) is higher than that of other three
treatments. Organoleptic properties of foods prepared from best
preservation method are as same as ordinary foods according to Duo
trio test.
Abstract: This paper addresses the design of hospital Intensive
Care Unit windows for the achievement of visual comfort and energy
savings. The aim was to identify the window size and shading system
configurations that could fulfill daylighting adequacy, avoid glare
and reduce energy consumption. The study focused on addressing the
effect of utilizing different shading systems in association with a
range of Window-to-Wall Ratios (WWR) in different orientations
under the desert clear-sky of Cairo, Egypt.
The results of this study demonstrated that solar penetration is a
critical concern affecting the design of ICU windows in desert
locations, as in Cairo, Egypt. Use of shading systems was found to be
essential in providing acceptable daylight performance and energy
saving. Careful positioning of the ICU window towards a proper
orientation can dramatically improve performance. It was observed
that ICU windows facing the north direction enjoyed the widest range
of successful window configuration possibilities at different WWRs.
ICU windows facing south enjoyed a reasonable number of
configuration options as well. By contrast, the ICU windows facing
the east orientation had a very limited number of options that provide
acceptable performance. These require additional local shading
measures at certain times due to glare incidence. Moreover, use of
horizontal sun breakers and solar screens to protect the ICU windows
proved to be more successful than the other alternatives in a wide
range of Window to Wall Ratios. By contrast, the use of light shelves
and vertical shading devices seemed questionable.
Abstract: In this study, we proposed two techniques to track the
maximum power point (MPPT) of a photovoltaic system. The first is
an intelligent control technique, and the second is robust used for
variable structure system. In fact the characteristics I-V and P–V of
the photovoltaic generator depends on the solar irradiance and
temperature. These climate changes cause the fluctuation of
maximum power point; a maximum power point tracking technique
(MPPT) is required to maximize the output power. For this we have
adopted a control by fuzzy logic (FLC) famous for its stability and
robustness. And a Siding Mode Control (SMC) widely used for
variable structure system. The system comprises a photovoltaic panel
(PV), a DC-DC converter, which is considered as an adaptation stage
between the PV and the load. The modelling and simulation of the
system is developed using MATLAB/Simulink. SMC technique
provides a good tracking speed in fast changing irradiation and when
the irradiation changes slowly or it is constant the panel power of
FLC technique presents a much smoother signal with less
fluctuations.
Abstract: The thermal performance of a solar water heating with
1.00 m2 flat plate collectors in Cascavel - PR, is which presented in
this article, paper presents the solution to leverage the marketing of
solar heating systems through detailed constituent materials of the
solar collector studies, these abundant materials in construction, such
as expanded polyethylene, PVC, aluminum and glass tubes, mixing
them with new materials to minimize loss of efficiency while
decreasing its cost. The system was tested during months and the
collector obtained maximum recorded temperature of outlet fluid of
55°C, while the maximum temperature of the water at the bottom of
the hot water tank was 35°C. The average daily energy collected was
19.6 MJ/d; the energy supplied by the solar plate was 16.2 MJ/d; the
loss in the feed pipe was 3.2 MJ/d; the solar fraction was 32.2%, the
efficiency of the collector was 45.6% and the efficiency of the system
was 37.8%.
Abstract: The performance of box-type solar cookers has been
reported by several researchers but little attention was paid to the
effect of the type of insulation material on the energy and exergy
efficiency of these cookers. This research aimed at evaluating the
energy and exergy efficiencies of the box-type cookers containing
different insulation materials. Energy and exergy efficiencies of five
box-type solar cookers insulated with maize cob, air (control), maize
husk, coconut coir and polyurethane foam respectively were obtained
over a period of three years. The cookers were evaluated using water
heating test procedures in determining the energy and exergy
analysis. The results were subjected to statistical analysis using
ANOVA. The result shows that the average energy input for the five
solar cookers were: 245.5, 252.2, 248.7, 241.5 and 245.5J
respectively while their respective average energy losses were: 201.2,
212.7, 208.4, 189.1 and 199.8J. The average exergy input for five
cookers were: 228.2, 234.4, 231.1, 224.4 and 228.2J respectively
while their respective average exergy losses were: 223.4, 230.6,
226.9, 218.9 and 223.0J. The energy and exergy efficiency was
highest in the cooker with coconut coir (37.35 and 3.90%
respectively) in the first year but was lowest for air (11 and 1.07%
respectively) in the third year. Statistical analysis showed significant
difference between the energy and exergy efficiencies over the years.
These results reiterate the importance of a good insulating material
for a box-type solar cooker.
Abstract: A model was constructed to predict the amount of
solar radiation that will make contact with the surface of the earth in
a given location an hour into the future. This project was supported
by the Southern Company to determine at what specific times during
a given day of the year solar panels could be relied upon to produce
energy in sufficient quantities. Due to their ability as universal
function approximators, an artificial neural network was used to
estimate the nonlinear pattern of solar radiation, which utilized
measurements of weather conditions collected at the Griffin, Georgia
weather station as inputs. A number of network configurations and
training strategies were utilized, though a multilayer perceptron with
a variety of hidden nodes trained with the resilient propagation
algorithm consistently yielded the most accurate predictions. In
addition, a modeled direct normal irradiance field and adjacent
weather station data were used to bolster prediction accuracy. In later
trials, the solar radiation field was preprocessed with a discrete
wavelet transform with the aim of removing noise from the
measurements. The current model provides predictions of solar
radiation with a mean square error of 0.0042, though ongoing efforts
are being made to further improve the model’s accuracy.
Abstract: Parabolic solar trough systems have seen limited
deployments in cold northern climates as they are more suitable for
electricity production in southern latitudes. A numerical dynamic
model is developed to simulate troughs installed in cold climates and
validated using a parabolic solar trough facility in Winnipeg. The
model is developed in Simulink and will be utilized to simulate a trigeneration
system for heating, cooling and electricity generation in
remote northern communities. The main objective of this simulation
is to obtain operational data of solar troughs in cold climates and use
the model to determine ways to improve the economics and address
cold weather issues.
In this paper the validated Simulink model is applied to simulate a
solar assisted absorption cooling system along with electricity
generation using Organic Rankine Cycle (ORC) and thermal storage.
A control strategy is employed to distribute the heated oil from solar
collectors among the above three systems considering the
temperature requirements. This modelling provides dynamic
performance results using measured meteorological data recorded
every minute at the solar facility location. The purpose of this
modeling approach is to accurately predict system performance at
each time step considering the solar radiation fluctuations due to
passing clouds. Optimization of the controller in cold temperatures is
another goal of the simulation to for example minimize heat losses in
winter when energy demand is high and solar resources are low.
The solar absorption cooling is modeled to use the generated heat
from the solar trough system and provide cooling in summer for a
greenhouse which is located next to the solar field.
The results of the simulation are presented for a summer day in
Winnipeg which includes comparison of performance parameters of
the absorption cooling and ORC systems at different heat transfer
fluid (HTF) temperatures.