A comparative analysis for multiattribute selection among renewable energy alternatives using fuzzy axiomatic design and fuzzy analytic hierarchy process

Renewable energy is the energy generated from natural resources such as sunlight, wind, rain, tides and geothermal heat which are renewable. Energy resources are very important in perspective of economics and politics for all countries. Hence, the selection of the best alternative for any country takes an important role for energy investments. Among decision-making methodologies, axiomatic design (AD) and analytic hierarchy process (AHP) are often used in the literature. The fuzzy set theory is a powerful tool to treat the uncertainty in case of incomplete or vague information. In this paper, fuzzy multicriteria decision- making methodologies are suggested for the selection among renewable energy alternatives. The first methodology is based on the AHP which allows the evaluation scores from experts to be linguistic expressions, crisp, or fuzzy numbers, while the second is based on AD principles under fuzziness which evaluates the alternatives under objective or subjective criteria with respect to the functional requirements obtained from experts. The originality of the paper comes from the fuzzy AD application to the selection of the best renewable energy alternative and the comparison with fuzzy AHP. In the application of the proposed methodologies the most appropriate renewable energy alternative is determined for Turkey.     

Multidimensional evaluation of global investments on the renewable energy with the integrated fuzzy decision‐making model under the hesitancy

This study aims to assess global investment alternatives with respect to renewable energy. Within this framework, five different renewable energy types (biomass, hydropower, geothermal, wind, and solar) are determined as investment alternatives. Moreover, eight different criteria are selected by considering the four different dimensions of balanced scorecard. Additionally, the fuzzy‐based decision making trial and the evaluation laboratory under the hesitancy (HF‐DEMATEL) model are taken into the account to weight these dimensions and criteria and the technique for order the preferences by the similarity to the ideal solution with the fuzzy hesitant methodology (HF‐TOPSIS) is considered to select the alternatives of renewable energy investments. The novelties of this study are to propose an integrated model and provide the balanced scorecard–based evaluations of global renewable energy investment alternatives. The findings show that learning and growth and customer are the most important dimensions for the investment on renewable energy. It is also identified that market potential, product customization, and technological development are the most significant criteria for this situation. On the other side, solar and wind energy are the most important renewable investment alternatives. These results explain that technological improvement should be maintained, and customer expectations should be met by the companies. Furthermore, solar power plant and wind power plant should be developed in the countries. For this purpose, governments should give necessary incentives to the investors, such as allocating appropriate lands. These actions can attract the attentions of the potential investors for these renewable energy alternatives. Owing to this issue, it can be possible to increase the capacity of electricity productions in the countries with a potential minimum cost.     

Wind farm site selection from the perspective of sustainability: A novel satisfaction degree‐based fuzzy axiomatic design approach

As a clean and renewable energy resource, wind energy is the most mature, environmentally friendly, and most commercially developed new energy resource in the world. Therefore, it is of great importance to determine the best location of wind farms to ensure the sustainable development of wind energy. However, since wind farm site selection often involves multiple criteria, which include qualitative and quantitative criteria, there may be conflicts between these criteria, so wind farm site selection is a complex multi‐criteria decision‐making (MCDM) problem. Therefore, the objective of this study is to propose a novel integrated MCDM approach using a fuzzy analytic hierarchy process and satisfaction degree‐based fuzzy axiomatic design (AD) to determine the optimal onshore wind farm site under a hybrid decision information environment. First, based on the literature review and experts' opinion, the evaluation index system for wind farm site selection is built from a sustainable perspective, which includes geographic, technical, economic, social, and environmental criteria. Second, fuzzy analytic hierarchy process is applied to determine criteria weights. Third, the satisfaction degree‐based fuzzy AD is employed to evaluate and rank alternatives under a hybrid decision information environment. Finally, a case study is used to illustrate the reliability and advantages of the method proposed in this paper. In addition, the information content of each alternative is calculated by aggregating the evaluation matrix of experts, and the results are IC₁ = 0.058, IC₂ = 0.096, IC₃ = 0.16, IC₄ = ∞, IC₅ = ∞, and IC₆ = 0.226. Then the satisfaction degree of each alternative is S₁ = 0.629, S₂ = 0.545, S₃ = 0.501, S₄ = 416, S₅ = 389, and S₆ = 0.463. Thus, the best wind farm site is A₁. Moreover, the results show that the method proposed herein is flexible and can effectively deal with the wind farm site selection problem. Although this paper chooses China as a case study, the proposed method herein is also applicable to other countries or regions.     

Hydrogen energy storage method selection using fuzzy axiomatic design and analytic hierarchy process

This paper presents an integrated Fuzzy Analytical Hierarchy Process (fAHP) and Weighted Fuzzy Axiomatic Design (wfAD) methodology for a strategic level problem of hydrogen energy storage (HES) method selection for Turkey. Considering alternatives of tank, metal hydride and chemical storage, we design our decision problem with respect to five assessment criteria as weight, capacity, storage loss and leak, reliability, and total system cost. In the solution methodology, we first implement fAHP to determine criteria weights by incorporating linguistic judgement and vague information. Next, we define functional requirements and design parameters for the selection problem and use wfAD to compare alternatives. After implementing the proposed integrated approach, we perform additional sensitivity analysis experiments to test the robustness of the solution with respect to changes in functional requirements.     

Optimization of electrical distribution networks fed by conventional and renewable energy sources

This paper provides a methodology for the optimization of an existing electrical distribution network when upgraded by renewable energies. The contribution of renewable energy in electricity generation is decided upon through both network design optimization and proper load management whereby applications that can be satisfied by non‐electrical means are separated from the main load. The remaining load will then be satisfied by an optimal mix of renewable energy which will be injected to the existing grid. The proposed problem will be formulated using multiobjective linear programming in conjunction with fuzzy logic. It will be shown that optimization using fuzzy logic can provide decision makers with more flexibility that would assist them in the allocation of various energy resources to optimally meet the various end uses and solve the problem of renewable energy connection to existing distribution networks. Copyright © 1999 John Wiley & Sons, Ltd.     

Investigation of solar energy utilization for production of hydrogen and sustainable chemical fertilizer: A case study

Renewable energies play a vital role in the economic and social development and progress of many countries. As one of the most significant sources of renewable energy, solar energy has been used due to its availability in many regions. Generating electricity for hydrogen production is one of the applications of solar energy. In petrochemical complexes, hydrogen is often used for producing fertilizers, especially urea fertilizers. The present study aims at investigating five major Iranian petrochemical complexes in terms of their suitability for the construction of a solar plant to produce electrolysis‐based green chemical fertilizers. To this end, a multicriteria decision‐making model is proposed, which includes the fuzzy analytic hierarchy process (AHP) and extended TODIM method of multicriteria decision making (including crisp, interval, and fuzzy numbers). The present research investigates 10 criteria for prioritizing petrochemical complexes, classified into four general categories, namely, climatic, geographic, environmental, and probability of natural disaster occurrence categories. Having calculated the weight of the criteria using the fuzzy AHP method, the alternatives are prioritized using the extended TODIM method. The methods of simple additive weighting (SAW), Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), and VIKOR were then used for validation of the results. Results showed that the Shiraz Petrochemical Complex has the highest priority and Khorasan Petrochemical Complex has the lowest priority for producing green fertilizer via solar energy–assisted water electrolysis. By using the solar system, Shiraz Petrochemical Complex can emit over 1900 tons less pollutants in the environment per day and provides up to 8% of its annual total production through clean energy.     

Locating wind farm for power and hydrogen production based on Geographic information system and multi-criteria decision making method: An application

Hydrogen generation from renewable energy resources is considered as a suitable solution to solve the problems related to the energy sector and the reduction of greenhouse gases. The aim of this study is to provide an integrated framework for identifying suitable areas for the construction of wind farms to produce hydrogen. For this purpose, a combined method of Geographic Information System (GIS) and multi-criteria decision making (MCDM) has been used to locate the power plant in Yazd province. The GIS method in the present study consisted of two parts: constraints and criteria. The constraint section included areas that were unsuitable for the construction of wind farms to produce power and hydrogen. In the present study, various aspects such as physical, economic and environmental had been considered as constraints. In the criteria section, eight different criteria from technical aspects (including average wind speed, hydrogen production potential, land slope) and economic aspects (including distance to electricity grid, distance to urban areas, distance to road, distance to railway and distance to centers of High hydrogen consumption) had been investigated. The MCDM tool had been used to weigh the criteria and identify suitable areas. Analytic Hierarchy Process (AHP) technique was used for weighting the criteria. The results of AHP weighting method showed that economic criteria had the highest importance with a value of 0.681. The most significant sub-criterion was the distance to urban areas and the least significant sub-criterion was the distance to power transmission lines. The results of GIS-MCDM analysis had shown that the most proper areas were in the southern and central sectors of Yazd province. In addition, the feasibility of hydrogen production from wind energy had shown that this province had the capacity to generate hydrogen at the rate of 53.6–128.6 tons per year.     

GIS based multi-criteria decision making for solar hydrogen production sites selection in Algeria

Hydrogen production from renewable energy sources appears to be an interesting solution for reducing greenhouse gas emissions and ensuring the energy security supply. This paper develops an integrated framework to evaluate land suitability for hydrogen production from solar energy site selection that combines multi-criteria decision making (MCDM) with geographical information systems (GIS); an application of the proposed framework for Algerian country. In GIS two types of criteria will be taken: constraints and weighting criteria. Constraints criteria will make it possible to reduce the area of study by discarding those areas that prevent the implementation of installing solar hydrogen production systems. These criteria will be obtained from the legislation (land use, water bodies, waterways, roads, railways, power lines, and also their buffer around them). Weighting criteria will be chosen according to the objective to be reached, in this case they will be the hydrogen demand, potential solar hydrogen production, digital elevation models (DEMs), slope, proximity to roads, railways, and power lines. Through the use of MCDM the criteria mentioned will be weighted in order to evaluate potential sites to locate a solar hydrogen production installation system. Analysis and calculation of the weights of these criteria will be conducted using Analytic Hierarchy Process (AHP). As a result, the final index model was grouped into four categories as “very low suitability”, “low suitability”, “moderate suitability” and “high suitability” with a manual interval classification method. The results indicate that 10.34% (246,272.02 km²), of the study area has very low suitability, 60.75% (1,446,907.65 km²) has low suitability, 6.68% (159,100.3 km²) has moderate suitability and 0.49% (11,669.21 km²) has high suitability for a solar-powered hydrogen production installation system. The other 21.74% (517,790.5 km²) of the study area is not suitable for such projects. The sensitivity analysis highlights that the suitable sites for solar hydrogen production installation system are dependent on the weights of the criteria that influence the decision. The MCDM methodology integrated with GIS is a powerful tool for effective evaluation of the solar-powered hydrogen production sites selection.     

GIS-based environmental assessment of wind energy systems for spatial planning: A case study from Western Turkey

Increasing population and life standards causes fossil fuel consumption to increase. Due to this increasing consumption, fossil fuels are being depleted rapidly. In addition to rapid exhaustion, another important problem associated with fossil fuels is that their consumption has major negative impacts on the environment. Therefore, many countries around the world have included renewable energy systems (RES) in their future energy plans so that they can produce reliable and environmentally friendly energy. Parallel to this trend, various RES have been identified and recently integrated into the current energy network of Turkey as well. However, it should be recognized that renewable energy resources are not fully environmentally safe. Different RES are associated with different environmental impacts. In planning the future energy development of a country, evaluation of renewable energy resources potentials together with their associated environmental impacts is critical. The aim of this study is to create a decision support system for site selection of wind turbines using Geographic Information System (GIS) tools. Wind energy potential and environmental fitness/acceptability are used as decision criteria for the site selection process. Potential environmental impacts of wind generation are identified in accordance with Turkish legislations and previous studies; and represented as fuzzy objectives of the decision problem. Wind potential map of Turkey generated by General Directorate of Electrical Power Resources Survey and Development is used to identify economically feasible locations in terms of wind energy generation. A study area composed of Usak, Aydin, Denizli, Mugla, and Burdur provinces in Turkey is selected and divided into 250 m × 250 m grids. Each grid represents an alternative location for a wind turbine or group of wind turbines. Fuzzy environmental objectives such as “Acceptable in terms of noise level”, “Acceptable in terms of bird habitat”, “Acceptable in terms of safety and aesthetics” and “Safe in terms of natural reserves” associated with wind turbines are identified based on previous research and each of these objectives are represented by a fuzzy set. Individual satisfaction degree of each of these environmental objectives for each grid is calculated. Then these individual satisfactions are aggregated into an overall satisfaction degree using various aggregator operators such as “and”, “or”, and “order weighted averaging.” Thus, an overall satisfaction degree of all the environmental objectives is obtained for each grid in the study area. A map of environmental fitness is developed in GIS environment by using these overall satisfaction degrees. Then this map is utilized together with the wind potential map of Turkey to identify both potentially and environmentally feasible wind turbine locations within the study area.     

Balance the wind power generation and transmission—case study in China

In most places in the world, the load center and the best wind resources are located far away from each other. Therefore, electricity generated from wind farms has to be transmitted to the load center over lengthy transmission lines. However, in some cases, lower quality wind resources also available close to load centers. Therefore, decision makers are sometime faced with competing alternatives: building wind farms in areas with higher wind speeds far away from load centers and or building wind farms in areas with lower wind speeds close to load centers. This paper proposes a methodology to help policy makers to develop wind resources cost effectively, balancing wind power generation from best wind resources and transmission of electricity over long distance. The methodology is applied to China, to compare development of high‐quality wind resources in the Three‐North region (north, northwest and northeast) and transmission of electricity to Southeast load centers to the development of lower quality resources closer to the same load centers. The results would help decision makers at the national and provincial levels to optimally develop the country's resources and assess the benefits of renewable energy trade between provinces. Copyright © 2015 John Wiley & Sons, Ltd.     

A methodology to generate statistically dependent wind speed scenarios

Wind power – a renewable energy source increasingly attractive from an economic viewpoint – constitutes an electricity production alternative of growing relevance in current electric energy systems. However, wind power is an intermittent source that cannot be dispatched at the will of the producer. Modeling wind power production requires characterizing wind speed at the sites where the wind farms are located. The wind speed at a particular location can be described through a stochastic process that is spatially correlated with the stochastic processes describing wind speeds at other locations. This paper provides a methodology to characterize the stochastic processes pertaining to wind speed at different geographical locations via scenarios. Each one of these scenarios embodies time dependencies and is spatially dependent of the scenarios describing other wind stochastic processes. The scenarios generated by the proposed methodology are intended to be used within stochastic programming decision models to make informed decisions pertaining to wind power production. The methodology proposed is accurate in reproducing wind speed historical series as well as computationally efficient. A comprehensive case study is used to illustrate the capabilities of the proposed methodology. Appropriate conclusions are finally drawn.     

A grey-based group decision-making methodology for the selection of hydrogen technologies in life cycle sustainability perspective

The objective of this research is to develop a grey-based group decision-making methodology for the selection of the best renewable energy technology (including hydrogen) using a life cycle sustainability perspective. The traditional grey relational analysis has been modified to better address the issue of uncertainty. The proposed methodology allows multi-person to participate in the decision-making process and to give linguistic evaluation on the weights of the criteria and the performance of the alternative technologies. In this paper, twelve hydrogen production technologies have been assessed using the proposed methodology, electrolysis of water technology by hydropower has been considered to be the best technology for hydrogen production according to the decision-making group.     

Use of MCDM techniques for energy policy and decision‐making problems: A review

Energy consumption increases all over the world as a result of industrialization in recent years. In this context, it has become important to meet increasing energy demand. It is significant to find alternative energy sources because of limited nonrenewable energy sources such as coal, petroleum, and natural gas. At this point, renewable energy sources have an important role to meet energy requirement. As a result, decision and policy making for energy is completely critical issue for countries. Various technical, economic, environmental, and social criteria are used to solve energy policy and decision‐making problems such as evaluation of energy projects, selection among energy alternatives, power plant site selection, and determining energy policy. Multicriteria decision‐making (MCDM) methods are used as effective tools to help decision makers while solving energy problems. There are a large number of studies including articles, conference papers, and book chapters, which examine energy problems by using MCDM methods in the literature. Therefore, analyzing these studies according to different features such as publication year, MCDM method, document type, statistical analyses, country, and published journal can be beneficial for leading researchers who study in energy decision‐making field. In this study, published papers, which use traditional MCDM methods to handle energy problems, are examined systematically. By the way, it is aimed to lead to researchers regarding MCDM methods which are utilized in energy applications. It also conducted some statistical analyses to obtain trends between years and MCDM methods. Besides, recent developments in energy field are presented through this comprehensive literature review.     

Developing a framework for renewable technology portfolio selection: A case study at a R&D center

The rapid development of technologies, their increasing complexity and variety, long lead times of R&D and market dynamics have made the task of technology selection difficult. Considering high level of competitiveness, organizations need to strategically allocate their limited resources to the best subset of possible projects.Today, the increased consumption of energy in modern industrial societies, in addition to the risk of quick exhaustion of fossil resources, has brought about irreversible and threatening environmental changes faced by the world. Dealing with these challenges, decision makers focus on the development of renewable energy technology viewed both as a process of diversification of energy sources and as a creation of an alternative energy option that will help curb down global climate change.To successfully tackle investment projects in renewable energy, it is essential to use models facilitating decision making process and guarantying the greatest possible value for organizations. Technology portfolio managers have traditionally used consensus-based tools, such as Analytical Hierarchy Process (AHP), Delphi but these tools are limited in their ability to fully quantify the impact of technology portfolio selection on the overall aspects of the system.This paper presents the results of developing a mathematical model for renewable technology portfolio selection at an oil industry R&D center maximizing support of the organization's strategy and values. The model balances the cost and benefit of the entire portfolio. It is also flexible and changes can be applied very easily.     

Storage technologies for wind power in the Columbia River Gorge

The transition from traditional energy sources to renewable has gained popularity and acceptance in recent years. This has been driven mainly by the current level of pollution, global warming, decommission of old nuclear power plants and the increasing cost of conventional energy sources. Nevertheless, one of the many steps to overcome is the seasonality or intermittency of renewable energy sources such as wind power. In recent years, new technologies have come up to address this problem, so the energy can be stored for future purposes. This paper analyses these energy storage alternatives for a specific case in the Columbia River Gorge for wind power. A hierarchical decision model is developed with criteria including political, social, environmental, technical and economical. The main conclusions highlight that the economical and technical criteria are among the most important ones for decision-makers.     

Optimal wind-hydro solution for Aegean Sea islands' electricity-demand fulfilment

Energy shortage and clean-water deficit, especially during the summer, are among the main factors delaying the economic development of Aegean Sea islands. All these islands possess an outstanding wind potential. However, the stochastic behaviour of wind speed leads to significant disharmony between wind energy production and electricity demand. Hence, the prospect of creating a combined wind-hydro energy production station is found to be a vital solution for all these islands, under the preconditions of maximum energy autonomy and limited first installation cost. Accordingly, a methodology of optimal wind-hydro solution estimation is developed and subsequently applied to several typical Aegean Sea island cases, in order to define the most beneficial configuration of the proposed renewable station. All numerical calculations are based on real data, like long-term wind speed measurements, demanded electrical-load and operational characteristics of the system components. In all cases analyzed, the renewable energy sources penetration exceeds 85%, while a significant part of the system's wind energy surplus is forwarded to a desalination plant for clean-water production.     

Genetic fuzzy rule extraction for optimised sizing and control of hybrid renewable energy hydrogen systems

A major challenge related to the design of a hybrid renewable energy hydrogen system is which energy sources to include and at what capacity, for regionally different potentials of renewable energy and hydrogen demand. In addition, once the plant is in operation, control variables need to be optimised. The problem resorts to an area of multiple criteria decision making referred to as multi-objective optimisation. The results obtained from these type of algorithms include not only one optimal solution, but a set of optimal solutions (Pareto front) thereby offering a system designer several options. This set of solutions can be hard to interpret and a method is needed to automatically extract useful design and control strategies from this information. A methodology that is quite successful in deriving human interpretable rules from this type of information is genetic fuzzy systems. In this work a k-means clustering algorithm is used to generate membership functions and a fuzzy rule-base is trained by means of a genetic algorithm. The genetic fuzzy system obtained is reduced by determining the minimum number of rules followed by a membership function reduction process. The reduced genetic fuzzy system is deemed more interpretable. Geographic weather data from three different sites are used to generate data to be used in the genetic fuzzy method. Results show that the technique provides valuable information that can be used for the design of such hybrid renewable energy hydrogen production systems.     

半结构多目标模糊优选理论在确定工程治涝标准中的应用

在区域除涝规划设计阶段,关键是要选择出合理的除涝工程标准。在选择的过程中,要考虑定量因素和定性因素。为协调各因素之间的复杂关系,提出将层次分析法和多目标模糊优选理论相结合,建立除涝工程标准方案多目标决策模型。运用层次分析法建立指标层次模型,根据不同决策人的偏好确定相应的指标权向量,在此基础上使用多目标模糊优选模型求解各方案最优相对隶属度,以确定最佳方案。经实例分析表明,该模型在确定区域除涝工程标准中具有重要的应用价值与现实意义,能为最后的总决策提供较为客观公正的依据。     

General sustainability indicator of renewable energy system based on grey relational analysis

This research answers the question of how to measure the sustainability of a renewable energy systems (RESs) as a physical parameter. Renewable energy is considered as a solution for mitigating the energy crisis, climate change and environmental pollution; however, an important problem of its application is that it is very difficult to evaluate the sustainability of RESs. This study develops a general sustainability indicator which is a tool to evaluate sustainability of RESs precisely and comprehensively. Based on the Triple Bottom Line approach, 11 Basic Sustainability Indicators with different dimensions and various units are selected from environmental, economic and social sustainability assessment criteria. In order to deal with the uncertainties in the definition and the assessment of sustainability, the grey regression analysis method is employed to quantify the basic indicators and to aggregate them into the general indicator. In addition, for explaining application of the general indicator, the cases of four RESs in hot‐arid Australia are presented. In the case study, the grey indicator is used to assess the sustainability of four systems with different combinations of grid, solar photovoltaic and wind renewable energy. The final results are compared with the general indicator based on fuzzy sets theory developed in previous studies. It is found that for the case of Australian system, the grey sustainability indicator has a good linear correlation to the fuzzy indicator results. The grey indicator is an effective way to assess the sustainability of RESs and provides a good tool for designers, users, decision makers and researchers. Copyright © 2013 John Wiley & Sons, Ltd.     

Distributed energy system selection for a commercial building by using Multi Criteria Decision Making methods

Turkiye has made a significant progress in liberalizing electricity generation, transmission and distribution systems. Utilization of Distributed Generation systems are encouraged to contribute to this liberalization process. It is a complex problem for the consumer to choose an appropriate combination of Distributed Generation systems. This complexity arises from the differences among the characteristics of Distributed Generation systems such as investment cost, operating cost, carbon emissions, primary energy consumption and primary energy utilization rate. Therefore, Distributed Generation system selection problem emerges as a multi criteria decision making problem. Finding the optimal alternative for many conflicting and interacting criteria can be achived by Multi Criteria Decision Making methods.In this study, the problem of choosing the most suitable alternative among 7 available Distributed Generation systems for a commercial building, which is a real-world problem, is discussed. First of all, 5 criteria were determined by considering the opinions of 23 experts in the field and the studies in the literature. The AHP method was used to weight the criteria according to 6 scenarios. Alternatives were ranked by using 6 Multi Criteria Decision Making methods (AHP, ANP, TOPSIS, ELECTRE, PROMETHEE, VIKOR). Spearman correlation analysis was performed in pairs on all 6 rankings for each scenario in order to identify which ranking is correct and the final ranking table was formed. The results showed that the criteria whose weights changed as a result of the scenarios according to the local conditions had an effect on the selection of the Distributed Generation system. In addition, the final ranking can be formed more accurately by performing correlation analysis of the rankings by using different multi criteria decision making methods.