Papers by Shafiqur Rehman
Energy Exploration & Exploitation, Feb 15, 2016
The use of renewable energy is increasing all over the world. These resources provide clean energ... more The use of renewable energy is increasing all over the world. These resources provide clean energy without giving rise to pollution. Current study discussed the feasibility of providing electricity by using hybrid power system (photovoltaic/wind/diesel) to a distant hypothetical village, population of 100 households with an average of five family members per household. The study area, Nooriabad, lies in Sind, Pakistan (latitude ¼ 25.17 N, longitude ¼ 67.8 E and site elevation ¼ 180 m above the mean sea level). Current study showed that the proposed hybrid system could be a viable solution for off-grid supply of electric power to remote areas in Pakistan. In the present case, a daily energy consumption of 205 kWh and a peak power demand of 47 kW were considered. The implementation of this project will result in the reduction of 69% in greenhouse gases addition in the local atmosphere of the chosen site. The photovoltaic/wind/diesel/battery hybrid system is found to be an attractive option with levelized cost of energy of 0.45 $/kWh and with renewable energy penetration of 84%. The sensitivity analysis showed that photovoltaic/wind/diesel/battery hybrid configuration is the only feasible system under given variations of different parameters.
An exponentially growing global population, power demands, pollution levels and, on the other han... more An exponentially growing global population, power demands, pollution levels and, on the other hand, rapid advances in means of communication have made the public aware of the complex energy situation. The Kingdom of Saudi Arabia has vast open land, an abundance of fossil fuel, a small population but has always been among the front-runners where the development and utilisation of clean sources of energy are concerned. Several studies on wind, solar and geothermal sources of energy have been conducted in Saudi Arabia. Solar photovoltaic (pv) has been used for a long time in many applications such as cathodic protection, communication towers and remotely located oil field installations. Recently, a 2MW grid-connected pv power plant has been put online and much larger solar desalination plants are in planning stage. Wind resource assessment, hub height optimisation, grid-connected wind farm and hybrid power system design were conducted in this study using existing methods. Historical daily mean wind speed data measured at 8 to 12metres above ground level at national and international airports in the kingdom over a period of 37 years was used to obtain long-term annual and monthly mean wind speeds, annual mean wind speed trends, frequency distribution, Weibull parameters, wind speed maps, hub height optimisation and energy yield using an efficient modern wind turbine of 2.75MW rated power. A further detailed analysis (such as estimation of wind shear exponent, Weibull parameters at different heights, frequency distribution at different heights, energy yield and plant capacity factor and wind speed variation with height) was conducted using wind speed measurements made at 20, 30 and 40metres above ground level. As a first attempt, an empirical correlation was developed for the estimation of near-optimal hub height (HH = 142.035 * (α) + 40.33) as a function of local wind shear exponent (α) with © © U Un ni iv ve er rs si it ty y o of f P Pr re et to or ri ia a iii a correlation coefficient of 97%. This correlation was developed using the energy yield from a wind turbine of 1 000kW rated power and wind speed and local exponent for seven locations in Saudi Arabia. A wind-pv-diesel hybrid power system was designed and specifications were made for a remotely located village, which is being fed 100% by diesel power generating units. The proposed system, if developed, will offset around 35% of the diesel load and therefore will result in decreased air pollution by almost the same amount. The developed wind speed maps, the frequency distributions and estimated local wind shear exponents for seven locations and energy yield will be of great help in defining the further line of action and policy-building towards wind power development and utilisation in the kingdom. The study also recommends conducting a wind measurement campaign using tall towers with wind measurements at more than one height and estimating the local wind shear exponents and developing a wind atlas for the kingdom. The study further states that a gridconnected wind farm of moderate capacity of 40MW should be developed using turbines of varying rated powers. The wind speed data was also analysed using wavelet transform and Fast Fourier Transform (FFT) to understand the fluctuation in wind speed time series for some of the stations. It is also recommended that policy-makers should take firm decision on the development of hybrid power systems for remotely located populations which are not yet connected with the grid. There are two challenges which need research: one is the effect of dust on the moving and structural elements of the wind turbines and the second is the effect of high prevailing temperatures on the performance and efficiency of the same.
FME Transactions
In the present work, solar water heating systems having nominal water usage of 24 cubic meters pe... more In the present work, solar water heating systems having nominal water usage of 24 cubic meters per day are considered. To identify the better option, both technologically and economically, a typical geographical location in Saudi Arabia, namely Abha, is considered. Internal rate of return (IRR) values for the solar collectors with glazing are found to be higher as compared with that of the unglazed type. The glazed type collectors are found to be more efficient, provide greater savings in fuel consumption, and result in the reduction of greenhouse gas (GHG) emissions. The findings of this study can be used for locations with similar types of climatic conditions in any part of the world.
FME Transactions
Globally, wind power is a technologically matured and commercially accepted technology. However, ... more Globally, wind power is a technologically matured and commercially accepted technology. However, intermittent and fluctuating wind speed makes it difficult to connect it directly to the grid. It becomes less attractive from the quality and continuous power supply point of view. Nevertheless, the wind speed is affected by meteorological parameters like temperature, pressure, and relative humidity and may be predicted better using all of these parameters or some of the theses as inputs. Since the weather conditions of a particular month repeat approximately after ten years and sometimes even year to year depending on geographical location. This study investigates the errors associated with predicting the wind speed of a particular calendar month using the historical data of the same calendar month in the previous years. Authors propose a strategy for long-term prediction of wind speed based on two nonlinear autoregressive neural network models, (i) nonlinear autoregressive neural netw...
Energies
Algeria is a wealthy country with natural resources, namely, nuclear, renewable, and non-renewabl... more Algeria is a wealthy country with natural resources, namely, nuclear, renewable, and non-renewable sources. The non-renewable energy sources are considered the lion’s share for energy production (98%). Algeria’s efforts to ensure and strengthen its energy security will take an important step in the coming decades by commissioning new energy infrastructure based on intensive use of water, coal, nuclear, non-renewable, and renewable sources. The implementation of new power infrastructure is expected to be operational from 2030. The renewable power realization in Algeria is relatively less compared to other African countries, i.e., Morocco, Egypt, South Africa, etc. The total renewable power installed capacity in Algeria reached 686 MW in 2020, as part of its national energy portfolio, although the Algerian government has spent tremendous efforts on introducing new sustainable technologies to enable the transition towards a cleaner and sustainable energy system. Indeed, the country ann...
Innovative Renewable Energy, 2022
The study presents the local values of wind shear coefficient (WSC) estimated using wind speed me... more The study presents the local values of wind shear coefficient (WSC) estimated using wind speed measurements made at 20, 30 and 40 m above ground level (AGL) during November 01, 1998 and October 12, 2002. The study also includes the local values of air density calculated using temperature and pressure measurement made at 2 m AGL during the same period. The mean wind speed above 4 m/s and the standard deviation values were used to obtain the turbulence intensities (TI) at different heights. These local values of WSC were used to estimate the wind speed at hub-height of the wind turbines used in this study. Energy yield was calculated for a hypothetical wind form of 60 MW installed capacity assumed to be consisting of 100, 60 and 30 wind turbines of 600, 1000 and 2000 kW from DeWind, respectively. The study recommends a value of WSC of 0.255 for the estimation of wind at different heights AGL and local air density of 1.06 kg/m 3 The WSC values were found to be higher during nighttime a...
This paper presents the wavelet-based analysis of meteorological parameters for nine meteorologic... more This paper presents the wavelet-based analysis of meteorological parameters for nine meteorological stations in Saudi Arabia. The study utilised the daily mean values of pressure, temperature, relative humidity and wind speed data over a period of 16 years between 1990 and 2005. In case of rainfall data, daily total values were used. The time series of meteorological parameters has so much noise that their overall shape is not visible upon visual inspection. It has been observed in the present investigation that trends become more and more readable at decomposition at different scales. The wavelet tools have been used to reveal the trends of the meteorological data time series. If the signal itself includes sharp changes then successive approximation look less and less similar to the original signal. This paper deals with the meteorological data visualisation. such as pressure, temperature, relative humidity, rainfall and the wind speed time series of the Kingdom of Saudi Arabia. Th...
Due to the availability of multi-megawatt wind turbines, ease of installation and maintenance, ec... more Due to the availability of multi-megawatt wind turbines, ease of installation and maintenance, economic compatibility and commercial acceptance, the power of the wind is being used globally for both grid-connected and off-grid applications. The power of the wind is intermittently available due to the fluctuating nature of the wind and hence needs to be understood well. Therefore, its variability in time and spatial domains was studied. The present work utilized daily mean values of wind speed from different meteorological stations spread over the Kingdom of Saudi Arabia in conjunction with wavelet transform and fast Fourier transform power spectrum techniques to understand the dynamic nature of the wind at nine stations. The study found that wind speed changed by ±0.6 to ±1.6 knots over a long period of about 10 years depending on the locations. The long-term mean wind speed of 5.6, 8.9, 6.25, 8.1, 6.0, 7.1, 6.0, 8.6 and 7.3 knots were obtained at Abha, Dhahran, Gizan, Guryat, Hail,...
Journal of Earth System Science, 2017
DESALINATION AND WATER TREATMENT, 2017
Renewable and Sustainable Energy Reviews, 2008
The objective of this paper is to prepare an update on the existing, on-going, and planned source... more The objective of this paper is to prepare an update on the existing, on-going, and planned sources of geothermal energy in Saudi Arabia. As per available information from the literature, there exists some lava activity in Madina AlMunawwara and hot springs in Wadi Al-Lith, Gizan, and Al-Hassa regions. The capacity and usage of these sources have to be explored both in terms of quality and quantity. A sample of water was collected from Wadi Al-Lith and a geochemical analysis was conducted in the laboratory. The results of the same are also included here in this country update report.
The increasing global population and more rapidly growing needs of energy have become matter of c... more The increasing global population and more rapidly growing needs of energy have become matter of concern to people from all walks of life. In order to meet power demands new and renewable sources of energy are being as supplemental source in addition to the regular fossil fuel based power generation. This paper presents the wind speed data, frequency distribution, local wind shear exponent, energy yield, air density and turbulence intensity analysis for a site located in the eastern region of Saudi Arabia. Overall mean wind speed values at 20, 30 and 40 meter above ground level were found to be 4.72, 5.34 and 5.74 m/s, respectively. The mean local wind shear exponent and air density were found to be 0.302 and 1.126 kg/m 3 , respectively. Lower turbulence intensities were noticed at higher altitudes. The proposed wind farm of 550MW installed capacity could generate 2,433.8 GWh of electricity with a plant capacity factor of 50.3% during the year.
This paper utilizes wavelets technique to calculate the Hurst exponent, the fractal dimensions an... more This paper utilizes wavelets technique to calculate the Hurst exponent, the fractal dimensions and finally the climate predictability indices of daily average time series of air temperature, surface pressure and precipitation for four coastal regions (viz., Dhahran, Gizan, Jeddah, and Yanbu) spread over east and west coasts of Saudi Arabia. The daily means of temperature, pressure and relative humidity and daily totals for precipitation data have been used in this study. The data covers a period of 16 years starting from 1990 till 2005. The Hurst exponents, calculated using wavelet method, were used to find the fractal dimensions for each of the meteorological parameters. Finally, the predictability indices of temperature, pressure and precipitation were used to establish the climate predictability indices. The climate predictability indices of precipitation and wind speed time series were found to be independent of the temperature and pressure. The predictability indices of individ...
In terms of energy, the Saudi Arabian land is gifted with huge resources of petroleum, natural ga... more In terms of energy, the Saudi Arabian land is gifted with huge resources of petroleum, natural gas, and solar energy. It also holds bright prospects of exploiting the other forms of energy such as the wind energy, nuclear energy, and the geothermal energy, because of its variety of geological features and environments. With respect to geothermal resources, there are 10 hot springs with varying deep temperatures of 50 to 120°C and different flow rates. In addition to this, there are three major harrats namely Khaybar, Kishb, and Rahat of geothermal interest. The crust thickness in these areas varies between 20 and 40 km and its lower part consists of mafic meta-igneous granulites. As of today, none of these are being used as source of electricity generation or heating purposes. It is believed that some of the thermal water springs can be utilized for electricity generation purposes in the time to come. 1. INTRODUCTION Exponentially growing global population, increasing pollution, cha...
FME Transactions
Accurate prediction of wind speed in future time domain is critical for wind power integration in... more Accurate prediction of wind speed in future time domain is critical for wind power integration into the grid. Wind speed is usually measured at lower heights while the hub heights of modern wind turbines are much higher in the range of 80-120m. This study attempts to better understand the predictability of wind speed with height. To achieve this, wind data was collected using Laser Illuminated Detection and Ranging (LiDAR) system at 20m, 40m, 50m, 60m, 80m, 100m, 120m, 140m, 160m, and 180m heights. This hourly averaged data is used for training and testing a Recurrent Neural Network (RNN) for the prediction of wind speed for each of the future 12 hours, using 48 previous values. Detailed analyses of short-term wind speed prediction at different heights and future hours show that wind speed is predicted more accurately at higher heights.For example, the mean absolute percent error decreases from 0.19 to 0.16as the height increase from 20m to 180m, respectively for the 12 th future ho...
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Papers by Shafiqur Rehman