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In this paper, a model to study the effect of inlet air-cooling on gas turbines power and efficiency is developed for two different cooling techniques, direct mechanical refrigeration and an evaporative water spray cooler. Energy analysis is used to present the performance improvement in terms of power gain ratio and thermal efficiency change factors. Relationships are derived for an open gas turbine cycle with irreversible compression and expansion processes coupled to air-cooling systems. The obtained results show that the power and efficiency improvements are functions of the ambient conditions and the gas turbine pressure ratio. The performance improvement is calculated for, ambient temperatures from 30 to 50°C, the whole range of humidity ratio (10–100%) and pressure ratio from 8 to 12. For direct mechanical refrigeration air-cooling, the power improvement is associated with appreciable drop in the thermal efficiency. The maximum power gain can be obtained if the air temperature is reduced to its lowest limit that is the refrigerant evaporation temperature plus the evaporator design temperature difference. Water spray cooling process is sensitive to the ambient relative humidity and is suitable for dry air conditions. The power gain and efficiency enhancement are limited by the wet bulb temperature. The performance of spray evaporative cooler is presented in a dimensionless working graph. The daily performance of the cooling methods is examined for an ABB-11D5 gas turbine operating under the hot humid conditions of Jeddah, Saudi Arabia. The results indicate that the direct mechanical refrigeration increased the daily power output by 6.77% versus 2.57% for the spray air-cooling. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In Saudi Arabia, the heating, ventilating and air conditioning (HVAC) system typically accounts for 65% of the total electrical energy consumption in buildings. This is due to a very high ambient temperature which persists for a long period of time in a summer season. Moreover, gas turbines efficiency decrease also with the high ambient temperatures. In the HVAC industry cool storage, or commonly known as Thermal Energy Storage (TES) is the most preferred demand side management (DSM) technology for shifting cooling electrical demand from peak daytime periods to off-peak night-time. The most popular and well-suited TES concept for Saudi Arabia is either chilled water or ice storage system, depending upon the applications and the required storage capacity. This paper shows how TES offers a means of reducing the electrical demand in large commercial buildings. Additionally, it is seen that efficiencies of the air cooled chillers are increased if they run overnight. Similarly efficiencies of gas turbine is also increased when a TES based pre-cooled air is used as an inlet to the turbine. This paper also discusses favouring conditions and other aspects of cool storage applications in Saudi Arabia. TES economics are considered and a cost analysis is presented to illustrate the potential savings that can be achieved by the use of TES in Saudi Arabia. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Due to population growth and industrial development in the Kingdom of Saudi Arabia (KSA), energy demand has increased. On the other hand, the consumption of fossil fuels has led to adverse environmental effects. This has led to government investment in clean energy. In many sectors of this country, there is good potential for using wind energy. Production of hydrogen from wind farms is a method for reducing energy swings, and it may also be utilized as a fuel in Saudi Arabia's businesses. As a result, the purpose of this research is to discover the best location for hydrogen generation from wind energy utilizing Multi‐Criteria Decision‐Making (MCDM) techniques. The criteria were weighted using the Step‐wise Weight Assessment Ratio Analysis (SWARA) approach. The most important criteria were determined to be "average wind speed," "number of refineries in the region," and "wind power density" with values of 0.2780, 0.2570, and 0.1570, sequentially. Then, the Weighted Aggregated Sum Product Assessment (WASPAS) approach was used to rank the locations. Finally, three other techniques, namely the Evaluation based on Distance from Average Solution (EDAS), the COmplex PRoportional ASsessment (COPRAS), and the Weighted Sum Model (WSM) were used to validate the results. Saudi Arabia's Eastern Province was recognized as the best position for hydrogen expansion in the country. The Eastern Province, with a rated capacity of 900 kW, was anticipated to produce 1863 MWh of energy and 30.16 tons of hydrogen every year. Highlights: Wind potential in Saudi Arabia was evaluated for hydrogen production.Location planning was analyzed to rank locations.multi‐criteria decision‐making (MCDM) methods were used for ranking.The best place to generate wind power was Eastern Province.A wind‐powered hydrogen facility in the Eastern Province was expected to produce 1862.95 MW of electricity and 30.16 tons of hydrogen per year using a wind turbine with a rated power of 900 kW. [ABSTRACT FROM AUTHOR]

This paper presents the analysis of sectoral energy and exergy utilization of Saudi Arabia by considering the energy and exergy flows for the 12 years between 1990 and 2001. Sectoral energy and exergy efficiencies are obtained for the subsectors and the devices used in each sector. Energy and exergy flow diagrams for Saudi Arabia are also presented, respectively, to illustrate the situation on how energy and exergy efficiencies vary in each sector. The residential sector appears to be the most energy efficient sector, and the industrial sector to be the most exergy efficient. It is believed that the current methodology is useful for analyzing sectoral energy and exergy utilization, which will help Saudi Arabia with energy savings through energy efficiency and/or energy conservation measures. It is also be helpful to establish standards to facilitate application in various sectors and processes for a sustainable energy planning. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: In March 2015, the Kingdom of Saudi Arabia signed an agreement with South Korea to build the system‐integrated modular advanced reactor (SMART) originally developed by the Korean Atomic Energy Research Institute. The SMART is a structurally contained safe dual‐purpose power plant reactor that produces both electricity and desalination. This study aims to design a double‐containment structure with a pool‐type concept to enhance the SMART safety and develop a robust design for future modular reactors. For that purpose, a theoretical model is developed herein, which leads to the modeling of a double‐containment structural design of a water pool. The model calculates various parameters (ie, temperature, pressure, phasic velocities, and condensable gases) and is used to develop a simulation program for use in a computational assessment. Moreover, two best‐estimate thermal hydraulic engineering programs, namely THEATRe and RELAP5, are used to simulate the original SMART with the double‐containment water pool structure. The differences in the modeling strategies of the two simulation techniques are discussed to accurately measure various technical parameters. Accordingly, a nodalization diagram of the reactor and the pool‐type concept are developed and simulated. The results obtained from the computational models yield the error of >2%, depicting accuracy. A small‐break loss of coolant accident is also simulated to mitigate the transient conditions. The result verifies the adoptability of this reactor concept in any other small modular reactor. [ABSTRACT FROM AUTHOR]

Summary: Saudi Arabia has plentiful freely accessible solar energy with daily total Direct Normal Irradiance on the higher side. Furthermore, because of its extensive desert land with over 2 million km2 expanse and high clearance index, the country could be a successful contender for accommodating the High Concentrator Photovoltaic (HCPV) technology. This technology, which assimilates Fresnel lens, has drawn more attention particularly after presenting III‐V Multi‐Junction solar cells for terrestrial uses since they keep achieving new conversion efficiency accomplishments. This article evaluates the HCPV performance in Saudi Arabia using direct normal irradiance data gathered in recent times. To undertake this assessment, a validated developed optical simulation using a ray‐tracing technique is employed to evaluate the maximum and average power output that may be gathered using a single HCPV unit in the primary regions and cities in the nation. Results indicate that the highest values for average and maximum annual power yield belong to the Western Inland area with one HCPV unit having a Fresnel lens with a 0.25×0.25 m2 aperture area, and those values are over 36 and 59 kWh, respectively. Concerning cities, Tabuk has HCPV unit producing the highest average annual yield greater than 39 kWh while the maximum annual yield crosses 60 kWh. Hence, the yearly electrical energy yield of 194 such units that use an area less than 12.2 m2 corresponds to approximately 33% of the electricity demanded yearly by a typical home in Saudi Arabia, which includes heavy energy‐consuming devices like air conditioners. Additionally, the estimated pollution potentially displaced by these units as per the global warming potential indicator is around eight tons of CO2 annually. [ABSTRACT FROM AUTHOR]

Summary: Hybrid energy systems (HESs) comprising photovoltaic (PV) arrays and wind turbines (WTs) are remarkable solutions for electrifying remote areas. These areas commonly fulfil their energy demands by means of a diesel genset (DGS). In the present study, a novel computational intelligence algorithm called supply‐demand‐based optimization (SDO) is applied to the HES sizing problem based on long‐term cost analysis. The effectiveness of SDO is investigated, and its performance is compared with that of the genetic algorithm (GA), particle swarm optimization (PSO), gray wolf optimizer (GWO), grasshopper optimization algorithm (GOA), flower pollination algorithm (FPA), and big‐bang‐big‐crunch (BBBC) algorithm. Three HES scenarios are implemented using measured solar radiation, wind speed, and load profile data to electrify an isolated village located in the northern region of Saudi Arabia. The optimal design is evaluated on the basis of technical (loss of power supply probability [LPSP]) and economic (annualized system cost [ASC]) criteria. The evaluation addresses two performance indicators: surplus energy and the renewable energy fraction (REF). The results reveal the validity and superiority of SDO in determining the optimal sizing of an HES with a higher convergence rate, lower ASC, lower LPSP, and higher REF than that of the GA, PSO, GWO, GOA, FPA, and BBBC algorithms. The performance analysis also reveals that an HES comprising PV arrays, WTs, battery banks, and DGS provides the best results: 238.7 kW from PV arrays, 231.6 kW from WTs, 192.5 kWh from battery banks, and 267.6 kW from the DGS. The optimal HES exhibits a high REF (66.4%) and is economically feasible ($104 323.10/year) and environmentally friendly. The entire load demand of the area under study is met without power loss (LPSP = 0%). [ABSTRACT FROM AUTHOR]

Summary: The aim of this research is to analyze the techno‐economic performance of hybrid renewable energy system (HRES) using batteries, pumped hydro‐based, and hydrogen‐based storage units at Sharurah, Saudi Arabia. The simulations and optimization process are carried out for nine HRES scenarios to determine the optimum sizes of components for each scenario. The optimal sizing of components for each HRES scenario is determined based on the net present cost (NPC) optimization criterion. All of the nine optimized HRES scenarios are then evaluated based on NPC, levelized cost of energy, payback period, CO2 emissions, excess electricity, and renewable energy fraction. The simulation results show that the photovoltaic (PV)‐diesel‐battery scenario is economically the most viable system with the NPC of US$2.70 million and levelized cost of energy of US$0.178/kWh. Conversely, PV‐diesel‐fuel cell system is proved to be economically the least feasible system. Moreover, the wind‐diesel‐fuel cell is the most economical scenario in the hydrogen‐based storage category. PV‐wind‐diesel‐pumped hydro scenario has the highest renewable energy fraction of 89.8%. PV‐wind‐diesel‐pumped hydro scenario is the most environment‐friendly system, with an 89% reduction in CO2 emissions compared with the base‐case diesel only scenario. Overall, the systems with battery and pumped hydro storage options have shown better techno‐economic performance compared with the systems with hydrogen‐based storage. [ABSTRACT FROM AUTHOR]

SUMMARY Integration of wind machines and battery storage with the diesel plants is pursued widely to reduce dependence on fossil fuels. The aim of this study is to assess the impact of battery storage on the economics of hybrid wind-diesel power systems in commercial applications by analyzing wind-speed data of Dhahran, East-Coast, Kingdom of Saudi Arabia (K.S.A.). The annual load of a typical commercial building is 620,000 kWh. The monthly average wind speeds range from 3.3 to 5.6 m/s. The hybrid systems simulated consist of different combinations of 100-kW commercial wind machines (CWMs) supplemented with battery storage and diesel generators. National Renewable Energy Laboratory's (NREL's) (HOMER Energy's) Hybrid Optimization Model for Electric Renewables (HOMER) software has been employed to perform the economic analysis. The simulation results indicate that for a hybrid system comprising of 100-kW wind capacity together with 175-kW diesel system and a battery storage of 4 h of autonomy (i.e. 4 h of average load), the wind penetration (at 37-m hub height, with 0% annual capacity shortage) is 25%. The cost of generating energy (COE, $/kWh) from this hybrid wind-battery-diesel system has been found to be 0.139 $/kWh (assuming diesel fuel price of 0.1$/L). The investigation examines the effect of wind/battery penetration on: COE, operational hours of diesel gensets. Emphasis has also been placed on un-met load, excess electricity, fuel savings and reduction in carbon emissions (for wind-diesel without battery storage, wind-diesel with storage, as compared to diesel-only situation), cost of wind-battery-diesel systems, COE of different hybrid systems, etc. The study addresses benefits of incorporation of short-term battery storage (in wind-diesel systems) in terms of fuel savings, diesel operation time, carbon emissions, and excess energy. The percentage fuel savings by using above hybrid system is 27% as compared to diesel-only situation Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY This study utilizes Abductory Induction Mechanism to estimate the mean monthly wind speed at some locations in Saudi Arabia based on wind data at other available recording stations in addition to some historical wind speed data at the target site. Wind speed data from 20 meteorological stations over a period of 16 years between 1990 and 2005 was used to accomplish the set objective. To validate the model, data from 19 stations was used to estimate the wind speed at the 20th location. Evaluation was performed for every one of the 20 available locations. Results show good agreement between estimated and measured monthly mean wind speed values. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Proper design and selection of building components at the early stages of the design process can greatly help in achieving thermal comfort with minimum reliance upon HVAC systems and, therefore, minimum energy requirements. Given today's complexities in building design as well as advances in computer technology, optimization techniques can beused as an aid to building designers in their decision making process. Office buildings are characterized by being 'internal-load' dominated with internal heat generation determining the need for energy to air-condition such buildings. This paper presents the results of applying an optimization model to the design of energy conserving office buildings in different climatic regions to test the impact of mainly envelope related parameters on the thermal performance of offices. Optimum sets of building design variables for three different sizes office building in four U.S. and two Saudi Arabian cities are presented with the objective of minimizing annual energy consumption for those buildings. ) 1997 by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]