Browsing by Author "Encinas-Oropesa, Adriana"
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Item Open Access A bi-objective decision support tool based on system dynamics and discrete event modelling for sustainable supply chain(DSRPT Consultancy, 2023-07-24) Yu, Jia; Hieu, Trung; Gray, Simon; Encinas-Oropesa, AdrianaBased on the development trend of sustainable concepts and the implement ability of composites combined with Agave Bagasse Fibre (ABF) and Polyethylene Terephthalate (PET). The purpose of this paper is to design a bi-objective decision support tool for supply chain of composite material which combined with ABF and PET. Through the production, processing, recycling, and reprocessing of composite materials, the sustainable supply chain model of four different schemes is designed, and the data results of each scheme model are calculated and analysed. The tool can support supply chain modelling solutions that seek best practices for sustainable supply chains and optimize resource efficiency through cost and carbon dioxide emissions. The sustainable supply chain model was designed, created, and optimized in AnyLogic software using System Dynamics and Discrete Event Simulation modelling methods based on the supply chain model established by previous researchers. According to the analysis results of the model data, the reasonable design of the whole process can effectively reduce the cost and carbon dioxide emissions and achieve the effectiveness and implementation of the sustainable supply chain. The results of this study will provide reference for more sustainable supply chain models in the future. Further research on composite materials can be carried out by combining with practice.Item Open Access The Capability of Design in Government(2020-03) Geraghty, Rhonda Nadine; Longhurst, Philip; Encinas-Oropesa, AdrianaThis research increases understanding of the scope and potential of design as resource in the context of government. Currently, there is limited knowledge and use of tangible and intangible dimensions of design in government and its potential remains unrealized. This despite designs established history of use, evidence to support its economic, social, environmental, and political value and encouragement from national and international bodies. What design is and its capacity to contribute in government is explored in this research. Accomplished through seven phases of investigations, the design-in- government context is first established and then explored followed by an examination of what design is and does within this context. A mixed methods approach was employed involving a critical assessment of both theoretical and empirical insights, including a scoping review, a focused review of literature, interviews with practitioners and primary and secondary observations of the design-in-government phenomena in practice. Interactions with stakeholders, academia and industry at international engagements informed the research process and evaluated study results incrementally over a 6-year period from 2013-2019. Results reveal a dimensional and holistic perspective of design as capability in operation within a dynamic design-in-government system. Here the potential exists for all facets of design to impact all areas of government simultaneously. The establishment of the design-in-government conceptual framework and definition of design for this context are also significant outcomes from this study. Together they constitute constructs that contribute to the furtherance of the novel field of research and practice with implications for design education and the evolving design profession. Finally, the distinctive scoping review process from this research contributes to the theoretical advancement of the methodology.Item Open Access Causal discovery to understand hot corrosion(Wiley, 2024-02-12) Varghese, Akhil; Arana-Catania, Miguel; Mori, Stefano; Encinas-Oropesa, Adriana; Sumner, JoyGas turbine superalloys experience hot corrosion, driven by factors including corrosive deposit flux, temperature, gas composition, and component material. The full mechanism still needs clarification and research often focuses on laboratory work. As such, there is interest in causal discovery to confirm the significance of factors and identify potential missing causal relationships or codependencies between these factors. The causal discovery algorithm fast causal inference (FCI) has been trialled on a small set of laboratory data, with the outputs evaluated for their significance to corrosion propagation, and compared to existing mechanistic understanding. FCI identified salt deposition flux as the most influential corrosion variable for this limited data set. However, HCl was the second most influential for pitting regions, compared to temperature for more uniformly corroding regions. Thus, FCI generated causal links aligned with literature from a randomised corrosion data set, while also identifying the presence of two different degradation modes in operation.Item Open Access Design and implementation of a novel user interfacing module for the Cranfield circular toilet.(Cranfield University, 2022-02) Noaman, Mohamad Waleed; Encinas-Oropesa, Adriana; Lighterness, PaulThis thesis presents empirical research on the development and implementation of a novel, water-saving user-interfacing module, that operates as a part of a comprehensive non-sewered sanitation system, the Cranfield Circular Toilet, that performs decentralized human waste evacuation and treatment. Building upon previous knowledge in this project, a prototype was designed, manufactured and assembled. It boasts new automated features that augment the functions of its mechanical evacuation subsystems, utilisation of water for interface flushing from the liquid purification process, and a streamlined design for manufacturability, in preparation for volume production and commercialization. Laboratorial tests were carried out to validate its main functionalities in self- cleaning and waste evacuation of solid and liquid human wastes to the backend treatment modules. Being a first prototype, findings from those tests were substantial in informing future design decisions in the module’s evolution, through selection of suitable and cost-effective operational features, optimisation of its geometric designs, and achieving further rationalisation in using resources, in aim to achieve higher levels of performance and user appeal, and a successful integration with the rest of the sanitation system.Item Open Access Designing a framework for materials flow by integrating circular economy principles with end-of-life management strategies(MDPI, 2022-04-02) Huang, Yuan; Shafiee, Mahmood; Charnley, Fiona; Encinas-Oropesa, AdrianaCircular economy is an upward trending notion that has drawn worldwide attention of policymakers, industry administrators, environmentalist as well as academic researchers. Though there are several tools developed for monitoring the material recovery, a very few number of research have been conducted to integrate circular economy principles with end-of-life (EOL) management strategies. This paper proposes an EOL-driven circular economy framework for the management of materials flow so as to extend the lifetime of materials through improved durability as well as to provide more social, economic and environmental benefits through less material waste. A case study from the agricultural waste industry is presented in order to test the model and validate its performance. The results show that the proposed framework has a good potential for small and medium enterprises (SME) advances.Item Open Access Effects of oxidation and hot corrosion in a nickel disc alloy(2008-12-31T00:00:00Z) Encinas-Oropesa, Adriana; Drew, G. L.; Hardy, M. C.; Leggett, A. J.; Nicholls, John R.; Simms, Nigel J.This paper describes work to study oxidation and hot corrosion damage in nickel disc alloy RR1000. Oxidation damage has been characterised via mass change data from thermogravimetric analyses at temperatures from 700 to 800 ºC and cyclic oxidation testing at 700 and 750 ºC. Thin oxide scales rich in Cr and Ti have been found to grow in a parabolic dependence with time. Oxidation rate constants have been correlated with temperature using an Arrhenius equation. Through the use of simplifying assumptions, mass change data have been converted to oxide thickness values. These values have been compared with observed values of oxide scale and the depth of near-surface damage, which have been measured using focused ion beam (FIB) microscopy. Hot corrosion of RR1000 has been studied in the laboratory by ‘deposit' recoat experiments at 700ºC. In these tests, samples were coated with deposits of Na2SO4/NaCl salt in a gas stream of air-300 vpm SO2. Corrosion damage has been quantified by dimensional metrology of samples before and after exposure. This enabled metal losses, i.e. the depth of corrosion pits, to be determined. Distributions of metal loss data were then generated to produce median damage values and exceedance cumulative probabilities. Finally, the effect of contaminants on the hot corrosion resistance of RR1000 has also been evaluated.Item Open Access Energy development and indigenous Mexican women: an implementation strategy approach in San Jose Villa de Allende, Mexico(Universidad Autonoma del Estado de Mexico, 2018-06-11) Whaites, Hannah; Encinas-Oropesa, Adriana; Zarza-Delgado, Martha PatriciaAccess to safe and sustainable energy is essential for human preservation and improvement of quality of life. Development is not possible without appropriate energy supplies. Arguably the biggest energy challenge of the 21st century is the health and wellbeing of 2.9 billion people globally who rely on burning biomass fuels in traditional stoves. This paper discusses the social and community level impact of using biofuels as an energy source in San Jose Villa de Allende, rural Mexico. Semi structured interviews were undertaken from indigenous women within the village. Picture evidence was also collected in order to identify the major energy problems of the community. The cooking stoves and fuels are identified as being the major contributors to time barriers and health issues for women. An implementation strategy for alternatives chimneys is suggested in order to develop policies for change and mitigate fuel poverty for an increased quality of life for rural Mexican women. The main discussion argues that cultural barriers and traditions are of foremost importance for policy making within the community.Item Open Access Fabrication of agave tequilana bagasse/PLA composite and preliminary mechanical properties assessment(Elsevier, 2020-05-15) Huerta-Cardoso, Omar; Durazo-Cardenas, Isidro; Longhurst, Phil; Simms, Nigel J.; Encinas-Oropesa, AdrianaBagasse agave tequilana fibres (ATF), an abundant by-product of Mexican tequila production, were characterised, treated and investigated as a reinforcement and filler material for polylactic acid (PLA) green composites. Two fibre pre-treatments were investigated: alkali (8% NaOH solution) and enzymatic (0.4% Pectate lyase solution). Composites pellets of 20, 40 and 60% (w/v) of ATF in PLA were manufactured using extrusion moulding. Press moulding was used to fabricate samples composite plates. Tensile, flexural, impact and water absorption properties were investigated on machined samples. Assessment of the mechanical properties showed tensile strength of up to 57.1 MPa for 20 % (w/v) of ATF untreated samples. Flexural strength up to 98.8 MPa and impact strength of 6.8 kJ/m2 for 40% (w/v) of ATF alkali treated samples. These values compare well with those of other new bio-composites. The values of the Young’s and flexural moduli are in proximity, if not superior, to those of widely used polymers PLA and GPPS. The optimal ATF loading was found to be ∼40%. Alkali treatment of fibres provided marginally improved mechanical properties; while significantly increasing the samples’ water absorption. Microscopy observations confirmed the two pre-treatments enhanced the fibre/matrix adhesion when compared with untreated fibres.Item Open Access Feasability study on maize husk as resource for a novel composite material(2018-08) Ruiz Trejo, Citlalli Elizabeth; Encinas-Oropesa, Adriana; Simms, Nigel J.Over the past decades, a dramatic increment on the production of maize husk (MH) in Mexico has been observed. Encouraging the study of this copious material as an alternative for the manufacture of composite materials, thereby enabling the use of MH. Offering advantages such as availability, renewability and more importantly the possibility to reduce local pollution levels without compromising the environmental integrity. The purpose of this research was to develop a maize husk-based composite (MHC) at a lab scale through a transdisciplinary systemic design approach (SDA). The SDA framework was developed from a designer point of view to confront the concerns of MH overproduction, including social, environmental, technical and economic implications. The investigated fibres were obtained from two harvesting methods: manual (MASH) and mechanical (ASPROS). Both MHF’s performance was lower than other natural fibres. ASPROS fibres showed a steadier mechanical performance with a cross-section area of 0.14 mm², an ultimate tensile strength of 45.75 MPa, a 7.65 % of elongation and Young’s modulus of 1.95 MPa. Nineteen different MHC blends were manufactured, at a concentration of 70/30 MH/binder. Four MH sizes with three binding systems were tested; the sizes were (1) whole husk, (2) chopped, (3) milled and (4) 10 % NaOH alkalinised fibres. The binding systems included: (A) a board made rearranging MH’s natural components through thermal fusion, (B) MH mixed with lignin for the production of non-resin MHC boards, and (C) MH blended with a super SAP® CPM epoxy resin (SSE). The sizereduction (milled and alkali) improved MHF’ surface interfacial bonding with SSE resin, however, only alkali treated presented enhanced tensile properties. Overall, the M30 boards met the properties of general purpose fibreboards for use under humid conditions (BS EN622-5:2009). The AK30 and M20 boards properties remained within the general-purpose fibreboards for use in dry conditions (BS EN622-5:2009).Item Open Access Feasibility study of a novel bio-based material through a design thinking approach.(2018-06) Huerta Cardoso, Omar Ivan; Encinas-Oropesa, Adriana; Longhurst, PhilipLandfilling of non-biodegradable materials is one of the most significant long-term pollution legacies. This practice represents a loss of energy-intensive produced materials alongside with an opportunity for recycling. Environmental and economic concerns arising from the large-scale production and consumption of oil-based materials, have led to an increased interest in developing more sustainable alternatives. Natural fibres (e.g. sisal, jute, flax, etc.) offer a potentially low environmental impact raw material for the packaging industry. Current research in the use of natural fibres in composite materials is reviewed initially in this work. This covers natural fibre properties, surface treatments, composite properties, and manufacturing processes. The rationale for the use of poly(lactic) acid (PLA) as a matrix system is defined. There are studies on the use of Agave tequilana fibres (ATF), but, there is no work reported to date attempting their use as a reinforcement/filler for poly(lactic acid) to replace polystyrene in consumer good applications. In this research, the importance of using a design thinking method in the development of more sustainable materials to be integrated into a circular economy, is established and principles for doing so are drafted. An initial life-cycle approach was used to design a biodegradable ATF and poly(lactic acid) bio-based composite. Experimental work included the development of different grades of fully degradable ATF/PLA bio-based composites using two diverse manufacturing processes; extrusion-press moulding, and film stacking. Bio-based composite properties were modified by exploring several surface treatments. Their resulting bio-based composite properties were investigated to provide enough information about the material behaviour in order to evaluate its potential uses. Mechanical and physical properties (tension, flexural, impact, and moisture) were assessed using standardised tests and methods. The possible routes for recycling or energy recovery of the material to close the material life cycle loop were explored. Despite the by-product character of ATF, it offers a potential low-cost alternative as a reinforcement source for bio-based composites. ATF were observed to have a density of 1.2±0.1 g/cm³ with a tensile strength of 79±38 MPa, and Young’s modulus of 3.3±1.4 GPa. Surface treatments improved ATF tensile properties and interfacial shear strength (IFSS) with PLA. Alkali-treated ATF resulted in a maximum improvement of ~50% in tensile strength and IFSS. According to the results obtained, ATF/PLA bio-based composites with a high fibre content of 60wt% have some properties capable of outperforming those of general purpose polystyrene in several conditions (i.e. ~15% in flexural modulus and ~17% in flexural strength), while in other cases properties did not presented significant improvements (i.e. Young modulus ~3 GPa). The impact of the new ATF/PLA bio-based composite on the current waste management system in Mexico was studied in terms of the “best” economic-environmental-social balanced route at the end-of-life of the material. It is considered that a continuous looping with the least possible loss of carbon and energy is best achieved through biological recycling. Anaerobic digestion of the material was ~14% after 20 days of incubation, with production of ~20 mL CH₄/gVS. Due to the performance presented regarding their economic viability and environmental acceptability within a circular economy, ATF/PLA bio-based composites have the potential to be used in non-structural applications within the consumer goods industry, e.g., packaging, casings for electronic appliances, crates, etc.Item Open Access Film-stacking method as an alternative agave tequilana fibre/PLA composite fabrication(Elsevier, 2022-06-18) Huerta-Cardoso, Omar; Durazo-Cardenas, Isidro; Longhurst, Philip J.; Encinas-Oropesa, AdrianaThis paper presents the fabrication of an Agave tequilana Fibre (ATF) bio-composite by film stacking method and an experimental investigation on preliminary mechanical properties; namely tensile, flexural, impact, and water uptake. Randomly oriented bio-composite samples were made from both, untreated and surface treated ATF collected from a tequila distillery waste stream. The ATF were surface treated using NaOH, and Pectate lyase to improve fibre properties and adhesion. The samples were prepared using three fibre loadings, 20, 40 and 60 wt%. Randomly oriented ATF mats were pre-impregnated with poly (lactic acid) (PLA) before bio-composite stacking and press moulding. Untreated fibre samples were processed and kept as a reference. The morphology of the fracture surfaces was analysed through optical and environmental scanning electron microscopy (ESEM). The quasi-static tensile tests revealed that the modulus of the bio-based composite materials is up to ~10% lower than that of the neat PLA. Flexural strength values observed at 60 wt% of fibre content were within the ranges of 76.10–77.0 MPa for treated samples with a flexural modulus of 3.36–3.76 GPa, whereas impact strength presented a reduction of ~32–35%. Generally, all measured properties presented reduction in strength with the increase of fibre loading.Item Open Access The hot corrosion of nickel-base disc alloys(Cranfield University, 2011-11) Potter, Andrew; Simms, Nigel J.; Encinas-Oropesa, AdrianaThe efficiency of a jet’s engines has a direct affect on its economic and environmental impact through the quantity of aviation fuel consumed and CO2 emitted. These factors are becoming increasingly important due to higher fuel costs and a greater global awareness of environmental issues. To date, most of the corrosion research work concerning jet turbines has focused on the hottest parts, the turbine blades vanes and combustion chamber. However, as the engines run hotter and with more stress, new superalloys have also been developed for the turbine disc. Although extensive research has been carried out with regard to the mechanical properties of these alloys, relatively little research has been done into their corrosion resistance. The aim of this research is to investigate the hot corrosion characteristics of both the existing and more recently developed disc alloys. Based on these data, the corrosion performance of these alloys was modelled and compared. These aims have been achieved using data from a series of “deposit recoat” corrosion tests on the relevant alloys carried out at Cranfield during the last 6 years. The alloys that are the focus of this study are: Waspaloy, Inconel 718, U720, and RR1000. RR1000 is of particular interest since it is the most recently developed alloy and relatively little is known about its corrosion properties. The tests have been carried over a range of temperatures relevant to the current operating temperatures and the desired higher operating temperatures of the turbine discs. The effects of deposition flux, deposit composition and exposure time have also been investigated as part of this study. A quantitative assessment of the corrosion damage has been carried out and provided metal loss data which has been used to generate empirical models and to compare the effects of variables. The data generated suggest that in the propagation stage of hot corrosion the rate of corrosion is approximately the same between alloys. Therefore the important factor when modelling a disc alloy’s corrosion behaviour is the length of the incubation period. The changes in elemental composition undergone at the alloy surface during corrosion have been investigated using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectroscopy (EDX). The results support the literature in that type II corrosion exhibits no preferential alloy depletion underneath the corrosion deposits.Item Open Access A new preparation method for 3D bio-composite filament manufacturing: a study on the effects of ball milling on the cohesion/adhesion of an agave tequilana bagasse/PLA pellet mixture(Springer, 2022-12-20) Salignon, Mathias; Gray, Simon; Rose, Timothy; Encinas-Oropesa, AdrianaThis study created a composite polymer for 3D printing from agave by-product using mechanical alloying process. The cold milling technique used by the ball mill is a standard procedure to homogenize metallic mixtures. This paper reports results from a series of laboratory tests to create a homogeneous mixture that could be extruded into a printable filament mixture of agave bagasse fibres and PLA pellets by using the kinetic energy of a ball mill. PLA and agave bagasse mixtures in this study were ground several times using this principle; steel and ceramic balls were used to grind them. The results of the study showed that this principle can be effective on a polymer-based mixture; indeed, an adhesion between the pellets and the agave bagasse fibres was obtained. The results showed the different parameters that influence the mixture quality as the milling time, the ball material, the number of balls, the mixture concentration and the rotational speed. Optical and ESEM/EDX analyses have confirmed our expectations about cohesion between fibres pulverized in powder and pellet adhesion, where powder accumulation on all the surfaces was detected. The absence of powder penetration in the pellets allowed us to explain the losses obtained during the process and to find new solutions to reduce them. Proof-of-concept parts were 3D printed with agave bagasse/PLA filaments. Their printed quality can be compared to that of commercial filaments. These results offer new perspectives to reuse agricultural by-products to create composite filament with a chemical-free manufacturing process.Item Open Access Performance comparison between isothermal hot corrosion and in situ cyclic hot corrosion of nickel-based superalloys(Springer, 2021-06-28) Syed, Adnan. U.; Martinez, Fabian Duarte; Roberts, Tracey; Encinas-Oropesa, Adriana; Morar, Nicolau I.; Grohne, Marlene; Frommherz, Martin; Nicholls, John R.; Gray, SimonAlthough a lot of work has been done to understand both major mechanisms of hot corrosion, namely type I (high-temperature hot corrosion) and type II (low temperature hot corrosion), there is very little information available on more representative cyclic performance in these regimes. This work addresses this by assessing the performance of isothermal (type I and type II) hot corrosion tests against combined (short and long) cyclic corrosion tests. Single-crystal alloy PWA 1484 and directionally solidified alloy MAR-M247 were assessed in all test regimes. Pre- and post-exposure dimensional metrology was used to quantify the corrosion damage and characterised using SEM/EDX. This paper highlights that the results of short cycle test conditions are more damaging compared to long cycle and standard isothermal type I and II test conditions. The cast nickel-based alloy MAR-M247 was found to be a better performer compared to PWA 1484 single-crystal alloy.Item Open Access Self-healing materials: a pathway to immortal products or a risk to circular economy systems?(Elsevier, 2021-07-01) Haines-Gadd, Merryn; Charnley, Fiona; Encinas-Oropesa, AdrianaProduct lifetime extension is key strategy for a functioning Circular Economy. Yet, the role of material innovation and how this might contribute to longer product and material lifetimes has not been widely discussed. Considering the significant environmental burden of material resource extraction, the longevity of materials must also be deliberated. Inspired by biological systems, self-healing materials are a type of smart material with the ability to inherently repair themselves when damaged. Although a technology extensively investigated within the material science community, the Circular Economy and product lifetime extension implications of implementing these into products has yet to be debated. Thus, this empirical study investigates: What are the benefits, opportunities, risks and challenges for applying self-healing materials to products within the context of the circular economy? In addition to a literature review, this research was carried out utilising a survey, two round table discussions, a workshop and interviews with industry experts from several different sectors. Through thematic analysis, it was discovered that the key benefits that self-healing materials might offer to circular systems are: the ability to maintain the primary lifetime of the product from both a technical and service lifetime perspective; assistance in the refurbishing and remanufacture of products through increasing the ease of disassembly and reassembly of products; and the potential to enable alternative business models. The key risks and limitations are: issues of persistence within the system; hybridization of materials - technosphere or biosphere? whether they will cycle in the system; limitations regarding their technology development, performance and lastly queries of their liability and compliance. These findings are valuable to both fields of self-healing materials and circular economy, and they not only demonstrate what sustainability factors must be understood when developing novel self-healing compositions but also expand our understanding for how these materials might be utilised to create longer lasting products from an industrial perspective. The paper concludes with a set of recommendations for future research activities which could not only help to advance the field of self-healing but also potentially product longevity and make immortal products a reality.Item Open Access Study of hot corrosion of single crystal superalloys and platinum-aluminide coatings(Cranfield University, 2005-10) Encinas-Oropesa, Adriana; Nicholls, J. R.; Simms, Nigel J.At the present time, combined cycle systems for power generation (e. g. IGCC), offer increased efficiency of power generation and lower environmental emissions, specifically C02, SOxg, and NO,,, as well as being adaptable to most fossil fuels. Economic factors, such as the cost of the materials must be considered. Materials influence the service lifetime in the required operational environment. Solid fuels like coal and biomass produce different combustion environments containing a range of contaminants that, when they reach their melting points, may cause accelerated corrosion, affecting directly the service life time of the gas turbine constructional materials. This accelerated corrosion is known as Hot Corrosion. The aim of this study was to develop, an understanding of the influence of these environmental factors on rate of hot corrosion of modem turbine materials, i. e. the single crystal alloys CMSX4 the SC2 , both uncoated and PtAl coated that are needed for a gas turbine blade and vanes operating in a range of hot corrosion environments expected in an lGCC plant. To achieve this aim, a series of laboratory corrosion tests was planned to simulate the same corrosion environment as in industrial high temperature gas turbine operation. Following established procedures for corrosion testing, samples were exposed in a controlled atmosphere furnace to a mix of gases (air/SO241CI) with a cyclic exposure time of 50 and/or 100h duration. Each cycle, samples were removed to be recoated with an alkali salt mixture to a total exposure time of 500h and or 1000h. Cross sections were examined by SEM/EDX to identify the mode of hot corrosion attack. To quantify the rate of corrosion, samples were measured pre-exposure and post-exposure, and this corrosion data was statistically assessed. Finally, from this quantitative data, life prediction models were developed to describe/predict the onset of hot corrosion and the corrosion rates observed under different gas compositions, and various deposition fluxes, both at typical type I and type II hot corrosion temperatures in terms of incubation and propagation periods. Separate models have been developed for the two single crystals superalloys: CMSX4 and SC2, in both the uncoated and platinum aluminide coated condition. The goodness of fit as defined by the regression coefficient varies from 0.88 to 0.99 for the propagation models at 700 and 900'C. The incubation models are as precise at 7001C but less precise at 9001C with regression coefficients of 0.78-0.94. IItem Open Access Survey data supporting 'Exploration of latent user needs for innovation in the sanitation industry'(Cranfield University, 2023-06-01 15:48) Marks, Emma; Abu-Bakar, Halid; Lighterness, Paul; Williams, Leon; Encinas-Oropesa, AdrianaCSV file containing survey resutls from 165 households with each survey covering a set of 15 questions around the topic of user behaviour relating to toilet habits in UK homes.Item Open Access A through-life cost analysis model to support investment decision-making in concentrated solar power projects(MDPI, 2020-03-27) Shafiee, Mahmood; Alghamdi, Adel; Sansom, Christopher L.; Hart, Phil; Encinas-Oropesa, AdrianaThis research paper aims to propose a through-life cost analysis model for estimating the profitability of renewable concentrated solar power (CSP) technologies. The financial outputs of the model include net present value (NPV) and benefit-cost ratio (BCR) of the project, internal rate of return (IRR) and discounted payback period (DPBP) of the investment, and levelized cost of energy (LCoE) from the CSP technology. The meteorological data for a specific location in the city of Tucson in Arizona is collected from a network of automated weather stations, and the NREL System Advisor Model (SAM) is applied to simulate hourly energy output of the CSP plant. An Excel spreadsheet tool is designed to calculate, in a bottom-up approach, the financial metrics required for approval of CSP projects. The model is tested on a 50MW parabolic trough CSP plant and the results show an annual energy production of 456,351,232 kWh, NPV of over $64 million and LCoE of 0.16 $/kWh. Finally, a sensitivity analysis is performed to identify the factors which have the most significant effect on the economic performance of CSP technologies. The proposed model can provide valuable guidance to support the strategic planning and investment decision-making in CSP projects.Item Open Access Toward baggage-free airport terminals: a case study of London City Airport(MDPI, 2021-12-26) Jiang, Yirui; Yang, Runjin; Zang, Chenxi; Wei, Zhiyuan; Thompson, John; Tran, Trung Hieu; Encinas-Oropesa, Adriana; Williams, LeonNowadays, the aviation industry pays more attention to emission reduction toward the net-zero carbon goals. However, the volume of global passengers and baggage is exponentially increasing, which leads to challenges for sustainable airports. A baggage-free airport terminal is considered a potential solution in solving this issue. Removing the baggage operation away from the passenger terminals will reduce workload for airport operators and promote passengers to use public transport to airport terminals. As a result, it will bring a significant impact on energy and the environment, leading to a reduction of fuel consumption and mitigation of carbon emission. This paper studies a baggage collection network design problem using vehicle routing strategies and augmented reality for baggage-free airport terminals. We use a spreadsheet solver tool, based on the integration of the modified Clark and Wright savings heuristic and density-based clustering algorithm, for optimizing the location of logistic hubs and planning the vehicle routes for baggage collection. This tool is applied for the case study at London City Airport to analyze the impacts of the strategies on carbon emission quantitatively. The result indicates that the proposed baggage collection network can significantly reduce 290.10 tonnes of carbon emissions annually.