Utilization Of Renewable Resources Research Articles

Utilization of renewable bio-based resources, viz. sorbitol, diol, and diacid, in the preparation of two pack PU anticorrosive coatings

The present work reveals utilization of renewable sources sorbitol, diacids, and 1,4-butanediol in synthesizing the polyol for polyurethane coatings rather than consumption of petroleum source based ingredients.

Feasibility and Estimation of Technical Potential and Calculation of Payback Period of Roof-Top Solar PV System in the City of Majmaah, Province of Riyadh, K.S.A

Depletion of fossil fuels in near future and accumulation of their emissions in the environment have attracted the world's attention to utilize renewable resources of energy. Oil and gas are the two main sources of power generation in Kingdom of Saudi Arabia. The problem of energy security, the aspect of environmental pollution and depletion of the known fuel reserves in future have created a scope for utilization of renewable resources. In this paper, the most feasible method of rooftop solar PV power generation will be evaluated. A techno-economic feasibility of rooftop PV solar power generation for the city of Al-Majmaah province of Riyadh, KSA is performed.

An Economic Assessment of Hybrid Renewable Energy for a Remote Area Electrification in Iran

The utilization of renewable resources is growing, in part due to the environmental impacts caused by fossil fuels. The largest sources of renewable energy are wind and solar and many predict that these energy sources will be increasingly used for distributed generation. In this paper, the feasibility is examined of a grid-independent system applied for a remote area electrification in Binalood, Iran. Traditional power systems for remote or rural areas are based on fossil fuels. After addition of renewable energy resources, solar energy applications have become popular in remote energy systems. The recent study and research works show that adding other possible renewable energy resources such as wind, hydro and biomass could make a hybrid system more cost-effective and environmentally friendly. Hence, in the present study, an overview of applied hybrid renewable energy system (HRES) for worldwide villages with special attention on Iran has been proposed to help present and future works for better achievement in this field. Furthermore sensitivity analyses are performed to determine the impact on performance of several key parameters: wind speed and fuel costs. HOMER was used to evaluate the feasibility of various hybrid systems. The results of a comprehensive feasibility data analysis along with its economic evaluation indicate that the wind-diesel hybrid system with battery storage is most efficient energy system for supplying this remote area's electrical energy demands.

Renewable Energy: A Solution to Hazardous Emissions

The problem of energy security, increasing prices of energy, the aspect of environmental pollution and depletion of the known fuel reserves in future have created a scope for utilization of renewable resources. Increasing prices of fossil fuels and costs associated with emissions may affect the economy of a country severely. Similarly, fossil fuels although produce useful energy, are responsible for production of harmful emissions like CO2, SOx, NOx etc. These dangerous emissions are an acute threat to human health on our plannet. The obvious choice available is to use renewable energy, which can play a critical role to mitigate these emissions. In this article, hazardous environmental effect of fossil fuels is discussed. The status of existing renewable energy technologies especially wind and solar energy and their future growth trend is presented in this article. In this article a focused literature review on research articles discussing the environmental impact of replacement of fossil fuel energy technologies with renewable technologies, with goals to prove that if fossil fuel energy is replaced by renewable technologies can be a solution to hazardous emissions. Last part of the article provides directions for renewable energy policies of a country, which could help to increase the renewable energy mix in the traditional energy production.

Cloning with kinetic and thermodynamic insight of a novel hyperthermostable β-glucosidase from Thermotoga naphthophila RKU-10T with excellent glucose tolerance

With a paradigm shift in industry, moving from natural fuels to alternative renewable resource utilization, the need of efficient thermostable cellulases are expected to increase in future. β-glucosidase, an essential member of cellulases that plays a critical role in cellulosic biomass degradation and in many biological processes. Therefore, a novel β-glucosidase gene encodes a protein (BglA) of 446 amino acid, belonging to glycoside hydrolase family 1 (GH1), was cloned from a hyperthermophilic bacterium Thermotoga naphthophila RKU-10T and over-expressed in Escherichia coli BL21CodonPlus. An extracellular BglA with a molecular weight of 51.50kDa, was purified to homogeneity by ion-exchange and hydrophobic interaction chromatography after heat treatment. Purified enzyme displayed optimal activity at pH 7.0 and 95°C. It was quite stable over a broad range of pH (6.0​–9.0) and temperature (60–90°C), fairly stable up to 8h at 80°C. Enzyme activity was stimulated by glucose concentration up to 600mM and exhibited high glucose tolerance with a Ki value of 1200mM. BglA showed great affinity toward p-nitrophenyl substrates and cellobiose. The Km, Vmax and Kcat values, against pNPG as substrate, were 1.5mM, 297mmolmg−1min−1 and 1527778s−1, respectively. Thermodynamic parameters for pNPG hydrolysis by BglA like ΔH*, ΔG* and ΔS* were calculated at 95°C as 25.7kJmol−1, 47.24kJmol−1 and −58.6Jmol−1K−1, respectively. It displayed a half-life (t1/2) of 5.21min at 97°C with denaturation parameters of enzyme including ΔH*D, ΔG*D and ΔS*D were 662.04kJmol−1, 110.10kJmol−1 and 1.491kJmol−1K−1, respectively. This is the first ever report on a highly glucose and thermotolerant β-glucosidase from T. naphthophila with high catalytic efficiency and low product inhibition, also exhibited independence of detergents and metal cations. All these significant features make BglA an appropriate candidate for biotechnological and industrial applications.

Energy Utilization of Renewable Resources in the European Union ― Cluster Analysis Approach

This paper analyzes and evaluates the European Union (EU) utilization of renewable resources in energy production and consumption. Biomass and renewable waste, with a share of 64.2% of primary renewable energy production, is the most important energy source in the EU. However, utilization of renewables in energy production and consumption differs across EU countries and is significantly influenced by various factors, including environmental, social, and economic characteristics. Cluster analysis was used to reveal these differences based on the identification and quantification of a set of factors reflecting the availability of renewable resources, utilization of renewable resources, and relevant socio-economic indicators. The results indicate that there are nine main identifiable clusters, considering the high variability of selected variables. The analysis confirmed that the economically developed EU countries with significant renewable resources have above-average primary energy production from renewable resources and biomass in particular. On the other hand, small EU countries are aggregated in numerous clusters characterized by under-average values in terms of availability and utilization of renewable resources such as wood production or energy consumption but with a relatively high share of renewable energy in gross final energy consumption.

Optimal deployment of renewable electricity technologies in Iran and implications for emissions reductions

In this paper, special focus is paid to the long-term adoption of renewable electricity technologies and their implications for emissions reductions in Iran. MESSAGE, as a bottom-up energy supply optimization model, is used to assess the lowest-cost technology options. The potential impacts of transitioning to a renewable electricity supply are quantified, and the investment requirement to achieve a low-carbon generation mix is estimated. Alternative scenarios are defined to evaluate the impact of fossil fuel prices, the carbon tax and government incentives on the utilization of renewable resources, national renewable targets, and emissions reductions. The prioritization of non-hydro renewable energy sources under different circumstances shows that wind is the most promising technology, followed by solar PV (photovoltaic), solar thermal and biogas. The findings demonstrate that the carbon tax would not individually be an effective strategy to reduce emissions. However, the carbon tax coupled with direct renewable subsidies would be more cost-effective, especially while fossil fuel prices are low. In the case of higher fossil fuel prices, the cost-effectiveness of carbon taxes at reducing emissions is not significantly influenced by the level of renewable subsidies.

Severe situation of rural nonpoint source pollution and efficient utilization of agricultural wastes in the Three Gorges Reservoir Area.

Rural nonpoint source (NPS) pollution caused by agricultural wastes has become increasingly serious in the Three Gorges Reservoir Area (TGRA), significantly affecting the reservoir water quality. The grim situation of rural NPS pollution in the TGRA indicated that agrochemicals (chemical fertilizer and pesticide) were currently the highest contributor of rural NPS pollution (50.38%). The harmless disposal rates of livestock excrement, crop straws, rural domestic refuse, and sewage also cause severe water pollution. More importantly, the backward agricultural economy and the poor environmental awareness of farmers in the hinterland of the TGRA contribute to high levels of rural NPS pollution. Over the past decade, researchers and the local people have carried out various successful studies and practices to realize the effective control of rural NPS pollution by efficiently utilizing agricultural wastes in the TGRA, including agricultural waste biogas-oriented utilization, crop straw gasification, decentralized land treatment of livestock excrement technology, and crop straw modification. These technologies have greatly increased the renewable resource utilization of agricultural wastes and improved water quality and ecological environment in the TGRA.

Robust Optimal Power Management System for a Hybrid AC/DC Micro-Grid

Hybrid ac/dc micro-grid is a new concept decoupling dc sources with dc loads and ac sources with ac loads, while power is exchanged between both sides using a bidirectional converter/inverter. This necessitates a supervisory control system to split power between its different resources, which has sparked attention on the development of power management systems (PMSs). In this paper, a robust optimal PMS (ROPMS) is developed for a hybrid ac/dc micro-grid, where the power flow in the micro-grid is supervised based on solving an optimization problem. Satisfying demanded power with maximum utilization of renewable resources, minimum usage of fuel-based generator, extending batteries lifetime, and limited utilization of the main power converter between the ac and dc micro-grids are important factors that are considered in this approach. Uncertainties in the resources output power and generation forecast errors, along with static and dynamic constraints of the resources, are taken into account. Furthermore, since uncertainties in the resources output power may result in fluctuations in the dc bus voltage, a two-level controller is used to regulate charge/discharge power of the battery banks. Effectiveness of the proposed supervisory system is evaluated through extensive simulation runs based on dynamical models of the power resources.

Uncovering driving forces on urban metabolism—A case of Shenyang

Exploring the sustainability of urban ecosystem is becoming a key area in global sustainable development. Urban metabolism is an effective analysis tool for the study of urban ecosystem. In this regard, how to evaluate the level of urban sustainable development and identify the key factors that affect urban metabolism is critical. Many studies on urban metabolism have been explored during the past half century, but few concerns about the key factors that affect urban metabolism. Therefore, this paper fills such a gap by combining emergy and Logarithmic Mean Divisia Index (LMDI) methods in order to analyze the sustainable development level and identify the driving forces of emergy utilization, respectively. A typical industrial city, Shenyang in northeast China, was chosen as a case study city in this paper. Results show that renewable resource utilization in Shenyang was very limited from 2000 to 2010, while nonrenewable resources and the imported resources increased rapidly. During this period, total emergy utilization of Shenyang increased from 8.52 × 1022 sej to 21.53 × 1022 sej, and emergy density increased with annual increasing rate of 10.34%, demonstrating a fast development of the economy and high level of resident's consumption. LMDI method was employed to analyze the driving forces of emergy consumption from the aspects of scale, structure and intensity. Results show that the rapid increase of emergy utilization in Shenyang was mainly caused by the expansion of economic scale, while emergy intensity greatly contributed to offset total consumption, and industry structure played a marginal role, with a minor value for its growth. Based upon these results, several policy recommendations were raised, including the use of more renewable and clean energy sources, a regenerative and preventative eco-industrial development approach, and capacity-building efforts, so that the overall environment pressure on urban development can be reduced.

Research progress in catalytic valorization of lignocellulose

Development and utilization of renewable biomass resources has great significance to ease the energy crisis and reduce enviromental pollution. Lignocellulosic biomass is much more concerned due to its abundant reserves, lower cost and fast-growing. The research progress of catalytic valorization of cellulose, hemicellulose and lignin were summarized. The catalytic conversion technology of lignocellulose such as thermo-chemical conversion, biocatalytic transformation and chemical transformation were introduced detailedly. The future development of utilization of lignocellulose was also previewed.

Capacitive effects of nitrogen doping on cellulose-derived carbon nanofibers

Carbons with valuable electrochemical characteristics are among the most convenient electrode materials used for energy storage. At the moment, their production is mostly reliant on unsustainable fossil fuels. A preferential sustainable production of enhanced carbonaceous electrodes can be achieved with more extensive utilization of abundant renewable resources instead of fossils. In this study, nitrogen-doped carbon nanofibers (CNFs) were synthesized from cellulose, the most abundant renewable resource, via consecutive steps of cellulose acetate electrospinning, subsequent deacetylation to cellulose, impregnation with nitrogen-containing additive (ammonium chloride), and carbonization. Results of material characterization showed that the carbonization of functionalized cellulose samples led to formation of CNFs doped with 4–5.6 at.% of nitrogen. In comparison with pristine CNFs N-doped samples had a slightly lower specific surface area, but higher conductivity and hydrophilicity. Moreover, electrochemical measurements indicated that the enhanced N-doped materials had about 2.5 times higher specific capacitance which was increasing throughout 1000 charge–discharge cycles. These results suggest that nitrogen doping method used in this study has a positive pseudocapacitive effect on the electrochemical performance of carbonized cellulose materials.

Wood polymer composites and their contribution to cascading utilisation

Due to a shortage of resources and a growing competition of land use, sustainable and efficient resource utilisation becomes increasingly important. The application and multiple, cascading utilisation of renewable resources is aimed at to ensure an allocation and future availability of resources. Wood polymer composites (WPCs) are a group of innovative materials consisting of mainly renewable resources. By means of summarizing recent research, it is shown how WPC can potentially contribute to an enhanced cascading utilisation. For the production of WPC, waste materials and by-products from wood and agricultural industry, e.g. offcuts, sawdust, residues from board manufacturing, pulping sludge, can serve as a raw material. Furthermore, the cited literature presents the use of recycled polymers and biopolymers as a potential alternative for the polymer component of WPC. By using biodegradable polymers, a fully biodegradable composite can be formed. In addition to using recycled materials and potentially being biodegradable, it is pointed out that WPC furthermore offers the possibility of being recycled itself, therefore being considered as a “green composite”. Although the influence of contaminated waste streams and mixed filler and polymer types on the properties of WPC made with such recyclates is yet not fully understood and no collection systems exist for post-consumer WPC, in-house recycling on the production sites is identified as a promising option as it reduces production costs and enhances resource efficiency and cascading utilisation. On the basis of cited life cycle assessments, the eco friendliness of WPC is assessed resulting in the conclusion that WPC cannot compete with solid wood with respect to environmental impact but is an environmentally friendly alternative to neat plastics in several applications.

Utilization of renewable resources: Condensation of glycerol with acetone at room temperature catalyzed by organic–inorganic hybrid catalyst

Organic–inorganic hybrid catalyst prepared from organic ammonium salt and heteropoly acid is reported as highly active and selective heterogeneous catalyst for the condensation reaction of glycerol with acetone at room temperature. The product formed during the reaction, solketal is a highly potential compound applied majorly in petroleum and pharmaceutical industries. The (C3H7)4N+/PWA catalyst performed better than other conventional solid acid catalysts like H-beta, amberlyst-15, montmorillonite K-10 and cesium salt of phosphotungstic acid with 94% glycerol conversion and 98% selectivity for solketal. The high activity of (C3H7)4N+/PWA catalyst can be explained by its acidity and pseudo liquid behavior. An independent study on the influence of water on catalyst deactivation was performed by adding a small amount of water (glycerol: water (1:1)) during the reaction. The (C3H7)4N+/PWA catalyst showed a remarkable resistance toward deactivation due to water with only a marginal decrease in conversion (∼3%) compared to other conventional solid acid catalysts like amberlyst-15, H-beta and montmorillonite K-10. (C3H7)4N+/PWA catalyst was truly heterogeneous and showed good reusability for 3 catalyst recycles.

Emergy-Based Sustainability Assessment for a Five-in-One Integrated Production System of Apple, Grass, Pig, Biogas, and Rainwater on the Loess Plateau, Northwest China

A five-in-one integrated production system (FIOIPS) was applied in the Weibei region of Shaanxi province, one of China’s major apple producing areas on the Loess Plateau. The FIOIPS comprises five linked organic subsystems, including apple, grass, pig, biogas, and rainwater. Despite being proposed as a cost-effective agroecosystem, the FIOIPS’s environmental sustainability and economic benefits remain unclear. In this study, we compared the FIOIPS with conventional (clean) tillage-based and grass-cultivation-in-orchard apple production systems commonly used in Weibei. Emergy flow and economic characteristics of the systems were analyzed by emergy and economic analysis using the emergy indices of transformity, renewability, emergy yield ratio, environmental loading ratio, emergy sustainability index, emergy exchange ratio, and feedback ratio of yield emergy. Although the FIOIPS has relatively low potential energy conversion efficiency and strong dependence on the inputs purchased from the market economy, it is superior to the other two systems regarding self-organizing capacity, renewable resource utilization efficiency, ecological environmental loading, economic benefits, and sustainability. From the perspectives of market economy and sustainability, the FIOIPS has promising applicability, feasibility and development potential for agricultural production on the Loess Plateau. Finally, disadvantages of the FIOIPS are discussed and possible solutions are provided for optimizing the integrated production system.

高校校园生态系统可控性

PDF HTML阅读 XML下载 导出引用 引用提醒 高校校园生态系统可控性 DOI: 10.5846/stxb201401040026 作者: 作者单位: 上海大学环境与化学工程学院,上海大学环境与化学工程学院,上海大学环境与化学工程学院,上海大学环境与化学工程学院,上海大学环境与化学工程学院,上海大学环境与化学工程学院,上海大学环境与化学工程学院,上海大学环境与化学工程学院 作者简介: 通讯作者: 中图分类号: 基金项目: Realization of a controlled campus ecosystem Author: Affiliation: School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University,School of Environmental and Chemical Engineering,Shanghai University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:在环境问题日趋严重的背景下,人类一直在探索将城市生态系统改造成能够自身循环、更好利用可再生能源、同时大幅减少排放的受控系统,但由于该系统的复杂度太高,可控程度较低,其实现难度很大。高校校园可视为比较典型的城市生态系统的子系统,在合理的管控与现代信息技术的支持下,高校校园最有可能实现生态系统可控化建设。对四个主要生态流(物质流、能量流、人口流、信息流)在高校生态系统中的作用进行理论阐述,针对具有中国特色、学生大规模集中居住的高校校园,提出了一种新的受控生态系统改造方案。通过对现有校园生态工程技术进行组装,完成校园生态系统基础构筑。利用综合的校园生态系统信息流管理平台监管校园物质循环、能量流动、人口流动,探讨了可实现的高校受控生态系统的建设模式,最终提出了高校受控生态系统建设的理论模型,以期达到高校校园物质与能源利用效率最大化,降低碳排放,改善局部小型气候群,进而改善环境大气候。研究结果如能较好的应用到实践中,将为城市生态系统建设提供重要参考,意味着现代生态学将为人类发展作出一定的贡献。 Abstract:The increasing seriousness of environmental problems is becoming a pressing social issue. Much attention is given to exploring ways to change this situation, with ecology being considered the most effective and sustainable solution. With increasing human development, cities have become the most important form of human settlement. Many studies have examined how to reform cities into managed ecosystems that are more self-contained, achieving a greater utilization of renewable resources and less contamination and emissions. In practice, it is difficult to realize such a system, due to the complex and uncontrollable behavior of city flows. However, college and university campuses may be viewed as representing a simplified eco-city that, through human intervention, is most likely to be reformed into a controlled ecological system through modern information technology and effective management. Thus, the authors investigated the possibility of realizing a controlled campus ecosystem. The study examined the main ecological flows within the ecosystem, which include flows of material, energy, population, and information. The role of the four ecological flows in the metabolism of a campus ecosystem is delineated in this article. At present, a university campus in China typically has many students, faculty, and staff who study, live, and produce there. The campus system has become increasingly energy-intensive and resource-intensive, subsequently discharging increasing quantities of waste to the environment. Therefore, it is necessary to find ways to reduce these outflows, such that the campus system becomes more sustainable. By recycling and reusing waste-water and solid waste, the campus may be transformed into an independent ecosystem. This process raises the possibility of a new approach to reform typical Chinese campuses. Ecological engineering technologies, such as solar energy, green roofs, the use of heat pumps, and high-tech information collection systems, etc., were applied to optimize the construction of the campus ecosystem. The Information Flow System (IFS) utilized data on human activities and the flows of energy and matter to more efficiently manage matter circulation and energy flow. This paper presents a theoretical model of how to form a controlled ecological system, and discusses the possibility of realizing the construction and management of an ecologically controlled campus. These efforts are expected to maximize the efficiency of energy and material use; thus, reducing carbon emissions and associated climatic and environmental impacts. If this theoretical model could be realized, it would provide a valuable reference for eco-city construction. Furthermore, this model would make a significant contribution the modern ecology of humans. 参考文献 相似文献 引证文献

Impact of Alkali Treatment Conditions on Kenaf Fiber Polyester Composite Tensile Strength

The increase of environmental issues awareness has accelerated the utilization of renewable resources like plant fiber to be used as reinforced material in polymer composite. However, there are significant problems of compatibility between the fiber and the matrix due to weakness in the interfacial adhesion of the natural fiber with the synthetic matrices. One of the solutions to overcome this problem is using chemical modification like alkali treatment. In this study, the impact of alkali treatment conditions on short randomly oriented kenaf fiber reinforced polyester matrix composite tensile strength was investigated. The experimental design setting was based on 2 level factorial experiments. Two parameters were selected during alkali treatment process which are kenaf fiber immersion duration (at 30 minute and 480 minute) and alkali solution temperature (at 40°C and 80°C). Alkali concentration was fixed at 2% (w/v) and the kenaf polyester volume fraction ratio was 10:90. The composite specimens were tested to determine the tensile properties according to ASTM D638-10 Type I. JOEL scanning electron microscopy (SEM) was used to study the microstructure of the material. The result showed that alkali treatment conditions setting do have the impact on tensile strength of short randomly oriented kenaf polyester composite. The interaction factors between immersion time and temperature was found to have prominent factors to the tensile strength of composite followed by the immersion time factor.

Natural resources complex of Russia: An unsustainable development trajectory

A brief geoecological analysis of Russia’s natural resources complex is presented in this work. The informational provision for the sphere of natural resources has worsened over the post-Soviet years. The role of industries based on mineral resources has been increasing. Imbalances are growing in the system of the extraction-processing-domestic consumption-export of mineral resources. The utilization of renewable natural resources is being ever more concentrated in compact areas near central locations and the main trunk roads. The boundaries of predominance in agriculture of plant cultivation are observed to have significantly extended from the latitudes of steppes in the 1980s to the tundra. As a result, the character and scales of agrarian impacts on natural complexes have dramatically changed. Important changes in the natural resources complex are not in conformity with the sustainable development criteria. A prominent role of natural complexes in the country’s economy determines the priority of the Earth sciences in the country’s science sphere, including geography and geoecology.

Developing an integrated supercritical fluid biorefinery for the processing of grains

With the rapid growth of the bioeconomy, there are major developments in the biorefinery concept to maximize utilization of renewable resources, including grains of cereals and oilseeds, targeting applications not only in food, nutraceutical, pharmaceutical and cosmetic products but also in biofuel, biochemical and biomaterial sectors. Supercritical carbon dioxide (SC-CO2) technology could have a major role to play in modern biorefineries. Know-how has been building on individual unit operations based on SC-CO2, especially extraction, fractionation and reactions involving lipids and particle formation for delivery of bioactives as summarized in this study mostly based on the previous work of the authors. Based on a solid understanding of fundamentals, the focus is now on optimal integration of these unit operations to build supercritical biorefineries. Such approaches should also consider integration of supercritical operations with conventional technologies for efficient and optimal process design. Even though the future of supercritical biorefineries seems to be bright, offering numerous advantages, there are also some substantial technical and economic challenges requiring further research.

Feasibility of satisfying electrical energy needs with hybrid systems for a medium-size hotel on Kish Island, Iran

The utilization of renewable resources is growing, in part due to the environmental impacts caused by fossil fuels. The largest sources of renewable energy are wind and solar and many predict that these energy sources will be increasingly used for distributed generation. In this paper, the feasibility is examined of a grid-independent system applied for a medium-size hotel in Kish Island, Iran. Furthermore, economic optimization is included in the assessment by using the Homer software as the optimization tool. Renewable and non-renewable energy sources (fossil fuels) are considered, and the final adoption of both cases is primarily based on their associated cost and efficiency. Sensitivity analyses are performed to determine the impact on performance of several key parameters: wind speed, solar radiation and fuel costs. The target location in this study is a hotel that has 125 rooms with the total annual electrical energy consumption of 2,628,000 kWh, and a peak demand of about 620 kW. The results of a comprehensive feasibility data analysis along with its economic evaluation indicate that the wind-diesel hybrid system with battery storage is most efficient energy system for supplying the hotel's electrical energy demands.