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Energy consumption in transportation accounted for over 29% of total final consumption (TFC) of energy and 65% of global oil usage, and it is highly connected to mobility. Mobility is essential for access to day-to-day activities such as education, leisure, healthcare, business activities, and commercial and industrial operations. This study examines the energy consumption for the transport industry, and the level of renewable energy development in some selected Sub-Saharan African (SSA) nations. This study relied on previous publications of government, reports and articles related to the subject matter. Vehicle ownership is fast increasing, particularly in cities. Still, it begins at a relatively low level because the area is home to countries with the lowest ownership rates worldwide. In its current state, the energy sector faces significant challenges such as inadequate and poorly maintained infrastructure, dealing with increasing traffic congestion in cities, large-scale imports of used vehicles with poor emission standards that affect air quality in cities, a lack of safe and formally operated public transportation systems, and inadequate consideration for women and disabled mobility needs. Motorcycle and tricycle are dominating the rural areas, accounting for a substantial amount of this growth. Aviation is the largest non-road user of energy, and this trend is predicted to continue through 2040 as Gross Domestic Product (GDP) grows and urbanisation expands. This study revealed the energy consumption for the transport industry, and the level of renewable energy development in some selected SSA. Rail and navigation lag behind current global levels. The usage of biofuel and rail transport was recommended.

This study presents thermodynamic analysis of the design and performance of eleven selected gas turbine power plants using the first and second laws of thermodynamics concepts. Energy and exergy analyses were conducted using operating data collected from the power plants to determine the energy loss and exergy destruction of each major component of the gas turbine plant. Energy analysis showed that the combustion chamber and the turbine are the components having the highest proportion of energy loss in the plants. Energy loss in combustion chamber and turbine varied from 33.31 to 39.95% and 30.83 to 35.24% respectively. The exergy analysis revealed that the combustion chamber is the most exergy destructive component compared to other cycle components. Exergy destruction in the combustion chamber varied from 86.05 to 94.67%. Combustion chamber has the highest exergy improvement potential which range from 30.21 to 88.86 MW. Also, its exergy efficiency is lower than that of other components studied, which is due to the high temperature difference between working fluid and burner temperature. Increasing gas turbine inlet temperature (GTIT), the exergy destruction of this component can be reduced.

In this study, exergoeconomic analysis and performance evaluation of selected gas turbine power plants in Nigeria were carried out. The study was conducted using operating data obtained from the power plants to determine the exergy efficiency, exergy destruction, unit cost of electricity and cost of exergy destruction of the major components of a gas turbine engine in the selected power plants. The results of exergy analysis confirmed that the combustion chamber is the most exergy destructive component compared to other cycle components as expected. The total efficiency defects and overall exergetic efficiency of the selected power plants vary from 38.64 to 69.33% and 15.66 to 30.72% respectively. The exergy analysis further shows that the exergy improvement potential of the selected plants varies from 54.04 MW to 159.88 MW. The component with the highest exergy improvement potential is the combustion chamber and its value varies from 30.21 MW to 88.86 MW. The results of exergoeconomic analysis show that the combustion chamber has the greatest cost of exergy destruction compared to other components. Increasing the gas turbine inlet temperature (GTIT), both the exergy destruction and the cost of exergy destruction of this component were found to decrease. The results of this study revealed that an increase in the GTIT of about 200 K can lead to a reduction of about 29% in the cost of exergy destruction. From exergy costing analysis, the unit cost of electricity produced in the selected power plants varies from cents 1.99 /kWh (N3.16 /kWh) to cents 5.65 /kWh (N8.98 /kWh).

This study aims to introduce a new modified method for estimating steam turbine high pressure (HP)-intermediate pressure (IP) leakage flow based on the experimental data extracted from a 250 MW re-heat steam turbine.

Effects of measurement uncertainties on the test results are investigated and key parameters are specified via a new modified method to diminish the test uncertainties. The recommended method is based on a constant IP turbine pressure ratio at the same loads. Considering this assumption, it was found that the turbine pressure ratio can be achieved in the second and the third tests with a much longer duration.

The results showed that the cross-over temperature is a major parameter in the leakage flow estimation tests, whereas hot reheat and cross-over pressures are the next priorities. It was also observed that as the cross-over temperature varies by 1°C, the estimated leakage flow error significantly differs by up to 72.6 per cent.

It is concluded that the present modified HP-IP leakage flow estimation method seems to be more accurate in comparison with previously proposed methods in literature.

The purpose of this paper is to analyze the wind energy technologies using the social network analysis based on patent information. Analysis of patent documents with social network analysis is used to identify the most influential and connected technologies in the field of wind energy.

In the literature, patent data are often used to evaluate technologies. Patents related to wind energy technologies are obtained from the United States Patent and Trademark Office database and the relationships among sub-technologies based on Corporate Patent Classification (CPC) codes are analyzed in this study. The results of two-phase algorithm for mining high average-utility itemsets algorithm, which is one of the utility mining algorithm in data mining, is used to find associations among wind energy technologies for social network analysis.

The results of this study show that it is very important to focus on wind motors and technologies related to energy conversion or management systems reducing greenhouse gas emissions. The results of this study imply that Y02E, F03D and F05B CPC codes are the most influential CPC codes based on social network analysis.

Analysis of patent documents with social network analysis for technology evaluation is extremely limited in the literature. There is no research related to the analysis of patent documents with social network analysis, in particular CPC codes, for wind energy technology. This paper fills this gap in the literature. This study explores technologies related to wind energy technologies and identifies the most influential wind energy technologies in practice. This study also extracts useful information and knowledge to identify core corporate patent class (es) in the field of wind energy technology.

This paper presents a conceptual model of effective subcontractor development practices to guide general contractors' development of a network of high-performing subcontractors (SCs) for Leadership in Energy and Environmental Design (LEED) projects.

Drawing from supplier development theories and practices in the manufacturing sector, a mixed interpretivist and empirical methodology is adopted to examine the body of knowledge within literature for conceptual model development. A self-reporting survey questionnaire with a five-point Likert scale is used to assess 30 construction professionals' perceptions of the effectiveness of 37 SC development practices classified into five categories. Descriptive statistics, weighted means, and t-tests are used for data analysis.

SC prequalification, commitment, incentives, evaluation and feedback practices can be effective in generating high-performing SCs. Practices that require more direct involvement and linkages between GC and SC are perceived to be less effective.

Theoretical contributions include a framework to foster future research to advance knowledge and understanding to enhance the adoption of SC development practices in the construction sector.

Implementation of ranked SC development practices can equip GCs with a network of high-performing SCs for improved competitive advantage and revenues.

The proposed conceptual model expands discussions on the modification of supplier development theories and practices currently utilized in the manufacturing sector toward their application in the construction sector. This research differs from previous research, which primarily focused on the manufacturing sector.

The purpose of this study is to perform an exergy analysis of a turbojet engine combustor at different cycle parameters.

Base cycle parameters have been defined for the engine, and then differentiation of the combustor exergy efficiencies and destruction rates have been evaluated by changing overall pressure ratio, combustor exit temperature and combustor pressure ratio.

For the basic engine cycle, combustor unit is found to have lowest exergy efficiency as 62.3 for the sea level static condition. Compressor turbine exhaust and whole engine exergy efficiencies have been calculated as 88.7, 96.5, 68.2 and 69.4, respectively.

Because of the biggest exergy, destruction is seen mainly in combustion system; effect of the combustor inlet pressure (related to the compressor design technology), pressure drop and exit temperature on the exergy efficiencies have been analyzed and combustor second law efficiency have been evaluated.

The investigation’s purposes are highly connected with social wellness and targeted at sustainable development of the society. Practical implementation of the obtained scientific results is directed on the improving of combustor for a turbojet engines and decreasing negative influence on the environment.

As a result of this paper, the following are the contribution of this paper in the field of gas turbine exergy subjects: Combustor has been found as the most critical component in respect of the exergy efficiency. Therefore, the effect of the combustor main cycle parameters such as inlet pressure, combustor pressure ratio and exit temperature have been analyzed.

The application of hybrid renewable energy system (HRES) can mitigate inadequate access to clean, stable and sustainable energy among households in sub-Saharan Africa (SSA). Available studies on HRES seem to concentrate only on its techno-economic and environmental viability. In so doing, these studies do not seem to underline the likely challenges that follow the acquisition of HRES by especially low-income households. The ensuing reality is, of course, a limitation in the use of HRES in homes with low incomes. It is therefore imperative to analyze how a household with low income can afford this kind of energy system. The purpose of this study, therefore, lies in presenting a techno-economic, environmental and affordability analysis of how HRES is acquired.

To arrive at a grounded analysis, a typical household in SSA is used as an example. The analysis focused on the pattern of energy use, and this is obtained by visiting an active site to evaluate the comprehensive load profile. In the course of analysis, an optimal techno-economic design and sizing of a hybrid PV, wind and battery were undertaken. Additionally, an acquisition analysis was done based on loan amortization.

The interesting result is that a combination of the photovoltaic-gasoline-battery system is the most cost-effective energy system with a net present cost of $2,682. The system combination can lead to an emission reduction of approximately 98.3 per cent, compared to the use of gasoline generating sets, common mostly in SSA. If an amortized loan is used to purchase the energy system, and the payment plan is varied such that the frequency of payments is made quarterly, annually, semi-annually, bi-monthly, semi-monthly and bi-weekly, it will be observed that low-income household can conveniently acquire a HRES.

The result presented a framework by which a low-income household can purchase and install HRES. To facilitate this, it is recommended that low-income households should be given interest-friendly loans, so as to enhance the acquisition of HRES.

Scenario planning is a useful approach that helps policymakers to better understand the complexity and uncertainties that lie in the future and to choose the right policy mix to support the development of renewable and affordable energy sources. In this regard, this paper aims to present renewable energy (RE) development scenarios in Iran in the horizon of 2030.

Following the intuitive logic school and the Global Business Network model, the authors identified seven driving forces, according to the expert’s judgment, by brainstorming techniques which influence REs development in the horizon of 2030. By prioritizing driving forces based on their importance and uncertainty, “sustainable and green economy” and “emerging technology development” are the most instrumental uncertainties and the authors formed a two-axis scenario matrix with each representing an axis.

The results suggest four main scenarios of “Transition to Sustainability with Green Gold,” “Towards Sustainability with Green Gold,” “Productivity with Black Gold” and “Desperation with Black Gold.” They include a wide range of possible situations of energy basket in the future ranging from dominance of fossil fuels to dominance of REs. The “Productivity with Black Gold” and the “Towards Sustainability with Green Gold” are the most probable scenarios of RE development by 2030 in Iran.

This paper indicates that the dominance of oil and gas resources would impede or at least slow down the development of renewable and affordable energy sources. Although the economic and environmental potentials and the inevitability of REs are well-understood, path dependence created by fossil fuels in Iran’s energy regime, either partially or fully, hinders the widespread development of REs which is the case in other resource-based countries as well.

This paper aims to understand the outlet temperature distribution of the combustor of a high-temperature, high-speed heat-airflow simulation system.

The paper uses numerical simulation to study the temperature distribution of the combustor of a high-temperature, high-speed heat-airflow simulation system. First, the geometrical model of the combustor and the combustion model of the fuel are established. Then, the combustion of fuel in the combustor is simulated by using FLUENT under various conditions. Finally, the results are obtained.

The paper found three conclusions: when the actual fuel–gas ratio is equal to the theoretical fuel–gas ratio, the temperature in the combustor of the high-temperature, high-speed heat-airflow simulation system (HTSAS) can reach its highest and the distribution is the most uniform. Although increases in the total temperature of the inlet air can increase the highest temperature in the combustor of the HTSAS, the average temperature of the combustor outlet will decrease. At the same time, it will lead to an uneven temperature distribution of the combustor outlet. When the spray angle of the kerosene droplet is at 30 degrees, the outlet temperature field of the combustor is more uniform.

The paper presents a method to analyze the combustion performance of fuel and the gas temperature distribution in the combustor. The results will lay the foundation for the gas temperature control of a combustor.