Orientador: Gabriel Alves da Costa Lima / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-21T23:40:04Z (GMT). No. of bitstreams: 1 Cesca_IgorGimenes_M.pdf: 2631356 bytes, checksum: 457c322ac2cc3cffc8315b485825f863 (MD5) Previous issue date: 2012 / Resumo: No setor energético (mineração, energia elétrica e petróleo), o conhecimento do comportamento dos custos dos equipamentos em seus ciclos de vida se torna muito importante devido a: (1) alto custo de aquisição e (2) elevadas despesas de manutenção. Dessa maneira, a aquisição de um ativo físico não deve ser decidida somente com base no custo inicial, mas sim por meio do custo do ciclo de vida desse ativo. Para esta dissertação foi elaborado um modelo matemático para encontrar a vida econômica e realizar previsões de custos de manutenção de um grupo de ativos físicos empregados no setor energético. Sendo assim, isso ocorre por meio de: (1) programação dinâmica, utilizando o modelo clássico de Bellman para reposição de equipamentos; (2) engenharia econômica, de tal forma que a vida econômica dos equipamentos é modelada por meio da função W de Lambert e (3) técnicas econométricas de previsão, tal que a relação entre os custos de manutenção e a idade dos equipamentos é testada por formas funcionais de regressões lineares simples. Com isso, para modelagem de vida econômica, foi possível estabelecer teoremas e, para previsão de custos de manutenção, foi possível perceber que as variáveis possuem uma relação não linear entre elas. Portanto, foi possível concluir que os equipamentos podem ser utilizados de maneira mais eficiente e com menores custos de ciclo de vida incorporados, uma vez que seja aplicada uma gestão econômica com base no modelo proposto nesta dissertação e, consequentemente, também possibilitar obter melhores indicadores financeiros para as empresas do setor energético / Abstract: In the energy sector (mining, oil and electricity), the knowledge of the asset's behavior in their life-cycle costs becomes very important because of: (1) the high cost of acquisition and (2) the high maintenance expenses. Thus, the acquisition of a physical asset should not be decided only on the basis of its initial cost, but through the consideration of its entire life cycle cost. In this dissertation a mathematical model of economic life and maintenance costs forecasts of a group of physical assets is developed and employed in the analysis of problems in the energy sector. The model considers the following: (1) dynamic programming, using the classical Bellman model for equipment replacement; (2) engineering economics, using to model the economic life of the equipment the equivalent cost theory and Lambert W-function and (3) econometric forecasting techniques, such that the relationship between the maintenance costs and equipment age are tested for functional forms of linear regressions. Therefore, on economic life modeling, it was possible to establish theorems and on maintenance costs forecasting. It was revealed that the variables have a nonlinear relationship between them. To conclude, physical assets can be used more efficiently and at lower life-cycle costs incorporated with the application of models developed in this dissertation and, consequently, contribute to obtain better financial indicators for companies in the energy sector / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo

Lately the construction industry has become more interested in designing and constructing environmentally friendly buildings (e.g. sustainable buildings) that can provide both high performance and monetary savings. Analyzing various parameters during sustainable design such as Life Cycle Assessment (LCA) and energy consumption, lighting simulation, green building rating system criteria and associated cost of building components at the conceptual design stage is very useful for designers needing to make decisions related to the selection of optimum design alternatives. Building Information Modeling (BIM) offers designers the ability to assess different design options and to select vital energy strategies and systems at the conceptual stage of proposed buildings. This thesis describes a methodology to implement sustainable design for proposed buildings at their conceptual stage. The proposed methodology is to be implemented through the design and development of a model that simplifies the process of designing sustainable buildings, evaluating their Environmental Impacts (EI), assessing their operational and embodied energy and listing their potential accumulated certification points in an integrated environment. Therefore, a Decision Support System (DSS) is developed by using Multiple Criteria Decision Making (MCDM) techniques to help design team decides and selects the best type of sustainable building components and design families for proposed projects based on three main criteria (i.e. Environmental, Economical factor «cost efficiency » and Social wellbeing) in an attempt to identify the influence of design variations on the sustainable performance of the whole building. The DSS outcomes are incorporated in an integrated model capable of guiding users when performing sustainable design for building projects. The proposed methodology contains five modules: 1) Database Management System (DBMS), 2) Energy and lighting analysis, 3) Life Cycle Assessment (LCA), 4) LEED and 5) Life Cycle Cost (LCC). To improve the workability of the proposed model, a use case of abovementioned modules are going to be created as plug-ins in BIM tool. The successful implementation of such a methodology represents a significant advancement in the ability to attain sustainable design of a building during the early stages, to evaluate its EI, and to list its potentially earned certification points and associated soft costs.

Många länder försöker minska sitt användande av fossila bränslen och istället använda sig utav förnyelsebara alternativ. Ett vanligt sätt att göra detta är att gå från bensindrivna motorer till eldrivna. Denna studie undersöker därför produkter ur samma produktsortiment som har samma grundfunktion och användningsområde men olika drivmedel. Syftet med detta är att få ökad förståelse för produkternas kostnader samt öka förståelsen för hur deras drift påverkar miljön. Studien genomfördes som en fallstudie på Swepac i Ljungby. Studiens genomförande följer delar ur LCC, LCA, CELA och break-even metoder för att kunna uppnå syftet. Miljöpåverkan mäts i koldioxidekvivalenter och en omräkningsfaktor används för att omvandla utsläppen till ett monetärt värde som går att använda i beräkningar av kostnader. Resultatet visar att ett break-even mellan maskinerna uppstår efter 6.9 år, livslängden är dock 5 år. Både miljöpåverkan, drift- och underhållskostnader är lägre för den eldrivna, dock gör den stora skillnaden i inköpspris att det tar lång tid innan ett break-even uppstår. / Many countries are trying to reduce the usage of fossil fuels and instead they are trying to find renewable alternatives. A common way to do this is to go from gasoline engines to electric engines. The purpose of the study is to gain a greater understanding of the products costs and environmental impact during their usage. The study was conducted as a case study at Swepac, Ljungby. The study’s implementation follows parts from LCC, LCA, CELA and the breakeven method in order to achieve the purpose. The environmental impact is measured in carbon dioxide equivalents and a conversion factor is used to convert the emissions to a monetary value that can be used in calculations of costs. The result shows that breakeven between the machines arises after 6.9 years, however, the service life is only 5 years. Both environmental impact, operating and maintenance costs is lower for the electrical option, however, the big difference in purchase price makes it take a long time for a breakeven to occur.

It is known that Sweden is categorised by being one of the regions that experience low solar radiation because it is located in the northern hemisphere that has a low potential of solar radiation during the colder seasons. The government of Sweden aim to promote a more sustainable future by applying more renewable initiative in the energy sector. One of the initiatives is by applying more renewable energy where PV panels will play a greater role in our society and in the energy sector. However, the produced energy from the PV panels is unpredictable due to changes in radiation throughout the day. One great way to tackle this issue is by combining PV panels with different energy storage system. This thesis evaluates an off-grid rowhouse in Eskilstuna Sweden where the PV panels are combined with a heat pump, thermal storage tank, including batteries and hydrogen system. The yearly electrical demand is met by utilizing PV panels, battery system for short term usage and hydrogen system for long-term usage during the colder seasons. The yearly thermal demand is met by the thermal storage tank. The thermal storage tank is charged by heat losses from the hydrogen system and thermal energy from heat pump.The calculations were simulated in Excel and MATLAB where OPTI-CE is composed with different components in the energy system. Furthermore, the off-grid household was evaluated from an economic outlook with respect to today’s market including the potential price decrease in 2030.The results indicated that the selected household is technically practicable to produce enough energy. The PV panels produces 13 560 kWh annually where the total electrical demand reaches 6 125 kWh yearly (including required electricity for the heat pump). The annual energy demand in terms of electricity and thermal heat reaches 12 500 kWh which is covered by the simulated energy system. The overproduction is stored in the batteries and hydrogen storage for later use. The back-up diesel generator does not need to operate, indicating that energy system supplies enough energy for the off-grid household. The thermal storage tank stores enough thermal energy regarding to the thermal load and stores most of the heat during the summer when there are high heat losses due to the charge of the hydrogen system. The simulated energy system has a life cycle cost reaching approximately k$318 with a total lifetime of 25 years. A similar off-grid system has the potential to reduce the life cycle cost to k$195 if the energy system is built in 2030 with a similar lifespan. The reduction occurs due to the potential price reduction for different components utilized in the energy system.

Syftet med rapporten är att sammanställa branschbaserat underlag för värdering av hållbart byggande som belyser vikten för val av ytterväggskonstruktion till flerbostadshus. Byggbranschen har länge fokuserat på att minska byggnadsverks energi- och miljöpåverkan under förvaltningsskedet. Det har haft mycket goda resultat och i dagsläget står förvaltningsskedet för ca 50 procent av hållbara byggnaders totala energianvändning. Projektering med långsiktigt perspektiv är nyckeln till hållbart byggande eftersom små förändringar kan ha stor inverkan under längre tid. Detta medför ökad betydelse för effektivisering under byggskedet. Utvecklingen av hållbara byggnader har resulterat i framtagning av nollenergi- och passivhus. De byggkoncepten ställer högre krav på klimatskalets byggtekniska egenskaper. Klimatskalet innefattar tak, grund, fönster, dörrar och ytterväggar. Samtliga komponenter har stor inverkan på byggnadens egenskaper. Rapporten belyser endast betydelsefulla egenskaper och olika aspekter för hållbara ytterväggskonstruktioner och hur de skall värderas. Rapportens mål är att ta fram ett anpassningsbart bedömningsverktyg med värderingsunderlag från 9 olika aspekter. Aspekterna som bedöms är byggbarhet, brand, fukt, estetik, förvaltning, inomhusmiljö, energiförluster, livscykelkostnad och miljöpåverkan. Bedömningsverktyget visualiseras som en mall där poängsättning används för aspekterna vilket möjliggör tydliga jämförelser mellan konstruktioner. Fakta analyseras och hämtas från en litteraturstudie samt intervjuer med en byggnadskonstruktör, en brand- och en fuktkonsult. De ligger till grund för bedömningsverktygets utformning. För att kunna tillämpa bedömningsmallen i byggbranschen väljs 6 ytterväggskonstruktioner med olika uppbyggnad och egenskaper. De är anpassade för koncepthus med hållbart byggande och uppnår krav från Boverkets byggregler och Passivhuskonceptet. Ytterväggskonstruktionerna prövas i mallen och våra resultat visar att mallen kan tillämpas och åskådliggöra skillnader mellan konstruktionerna. Ytterväggarna erhåller ett generellt betyg samt ett viktat betyg som utgår från en anpassningsbar viktfaktor. Möjlighet för vidareutveckling finns för bedömningsmallen. Mallen är generell och tillämpningsbar på konstruktioner med andra egenskaper än de valda i rapporten. Rapporten indikerar på att mallen kan anpassas för att möjliggöra val av fördelaktiga konstruktioner för olika klimatzoner och beställarens ändamål. / The report aims to bring together industry-based data for evaluation of sustainable building that shows the importance of the choice regarding exterior wall construction for apartment buildings. The construction industry has focused on reducing the energy and environmental impact on buildings during the management phase for a long time. The results have been positive and to this date, the management phase stands for 50 percent of sustainable buildings total energy use. Designing with a long-term perspective is the key to sustainable building, because small changes can have a big impact over time. The importance of energy efficiency during the construction phase has increased. The results of the development regarding sustainable building have increased the production of zero energy- buildings and passive houses. The new concepts of building technology are placing higher demands on the technical properties of the building envelope. A building envelope includes roofs, foundation, windows, doors and exterior walls. All components have a major impact on the technical properties of a building, but the report only highlights significant aspects of sustainable exterior wall constructions and how they should be evaluated. The goal of the report is to develop an adapted assessment tool with evaluation data from 9 different aspects. The aspects that we will review in the report is constructability, fire, moisture, aesthetics, management, indoor environment, energy losses from the exterior wall construction, life cycle cost and environmental impact. The assessment tool is portrayed as a template that rates and scores different exterior wall construction. This enables clear comparisons between structures. The basic facts for the report are retrieved from a literature study. Interviews with a structural engineer and a fire- and moisture consultant have been conducted for a deeper view on how the construction industry evaluates and scores exterior wall construction. To apply the assessment template for trade and industry, 6 exterior wall constructions with different structures and properties were selected. They were suitable for conceptual houses with sustainable building technology and are the basis for achieving requirements from National board of housing and passivehouse rules. The different exterior wall constructions were tested on the template and the results show that the model can be applied positively on them. The different constructions receive a general grade and a weighted grade. The weighted grade is based on a customizable weight factor. The assessment template illustrated the differences between them. Possibilities for further development of the assessment template exist. It’s possible to apply the template on structures with different kind of properties than the ones chosen for this project. The template can be a tool for choosing a construction based on the demands from a client and it can be adapted to different kind of climate zones.

When implementing a bridge design proposal, it is common that several alternatives be considered, each with a different material of construction. Traditional building materials used for the construction of bridges have mainly been concrete, steel, timber or aluminium. With all these materials options, maintenance and replacement costs throughout the lifespan of a bridge make up for a large proportion of their total life cycle costs. Fiber Reinforced Polymer (FRP) provides a new viable construction material, which can be implemented in bridge construction. This plastic based material has favourable material properties such a very high strength to weight ratio, high corrosion resistance and durability, as well as very low maintenance costs over its lifetime. In the feasibility analysis, a case study of an existing FRP deck bridge was taken and examined in three aspects: structural, economic and environmental. The bridge was also redesigned with a concrete deck solution, to provide a comparison to a conventional construction material. The results were found, in general to be favourable towards the FRP solution. From the structural analysis savings on deflection, support reactions and superstructure stresses were outputted. Economically, the composite material was found to have a substantial higher initial cost but much lower periodic maintenance costs than the concrete option. Finally the FRP bridge option displayed a lower construction time for the superstructure, at one third of that of concrete and an overall lower environmental impact, based on material production and the overall bridge construction process.

Studien syftar till att ta fram rekommenderade livscykelplaner för övergångskonstruktioner för att i framtiden möjliggöra säkrare livscykelkostnadsanalyser. Nedbrytningen av övergångskonstruktioner kan grovt delas upp i två kategorier, användarrelaterad nedbrytning samt nedbrytning associerat med rådande klimatförhållanden. I studien har årsdygnstrafiken och klimatzonernas påverkan på övergångskonstruktionen studerats genom utvärdering av historiskt utförda åtgärder kopplade till Trafikverkets broförvaltningssystem BaTMan. Regressionsanalyser och överlevnadsanalyser utfördes för de vanligaste åtgärderna. Resultaten visar att utbyte av tätprofil samt övergångskonstruktion är de åtgärder som förekommer allra mest och sker i genomsnitt efter 25 respektive 33 år. Från analyserna kunde utläsas att trafikintensiteten är en faktor som direkt påverkar nedbrytningen och således reparation och utbyte av övergångskonstruktion, troligt är även att tung trafik står för en stor del av nedbrytningen. Även klimatet verkar ha en påverkan på både övergångskonstruktionens och tätprofilens livslängd. Baserat på resultaten rekommenderas tre livscykelplaner, livscykelplanerna kan användas som underlag i framtida livscykelberäkningar. De kan även användas som stöd för förvaltare vid uppbyggnad av strategier under förvaltningsfasen. / This study aims to develop recommended Life-Cycle Plans for bridge expansion joints which in the future can be used for Life-Cycle Cost analysis to achieve a higher degree of certainty. The degradation of expansion joints can be roughly divided into two categories, user-related degradation and degradation due to climatic conditions. In the study, the influence of annual average daily traffic and climate zones on the expansion joint will be studied by evaluating historically conducted maintenance actions related to the Swedish Transport Administrations (Trafikverket) bridge management system BaTMan. Regression analysis and survival analyzes were performed for the most common actions. The results show that replacement of the strip seal and the expansion joint is the most commonly performed maintenance measures and occurs on average after 25 and 33 years. From the analyzes it was deduced that the traffic intensity is a factor that directly affects the degradation and therefore also the repair and replacement of the expansion joint, likely is also that a large part of the degradation is due to the wear of heavy vehicles. The climate also seems to have an impact on the lifetime of the expansion joint as well as the strip seal. Based on the results, three Life-Cycle Plans was recommended. These Life-Cycle Plans can be used for future Life-Cycle Cost calculations but also to support bridge managers when comparing different maintenance strategies during the operational phase.

Construction of infrastructure does not only mean large capital investments but also future costs to operate and maintain these assets. Decision making in planning and design of roads will impact the need of future operation and maintenance activities. Additionally, infrastructure management is often under increasing pressure of aging structures, limited budgets and increased demands from public which require transparency in the decision making. Life cycle costing is a methodology that takes into account costs throughout an asset’s life cycle including investment, operation, maintenance and disposal. Despite the methodology’s existence for more than 40 years, the practical application is often reported to be scarce in both private and public sectors. Implementation in road planning and management means a high complexity where the life cycle costing can to be applied from early planning, design, construction and management in which all influence life cycle cost. Life cycle costing can also be applied in many different ways, level of detail and for different type of studies. For effective implementation of life cycle costing in road planning, design and management, different considerations need to be understood. In this thesis the application of life cycle costing has been studied through case study research. The main case selected was an investment to convert a single carriageway road to a, so called, sparse collision-free road. Through widening and separation between driving directions the traffic safety is significantly improved. However, in recent years increased operation and maintenance costs have been associated with the road type. Especially concerns regarding increased road user cost during road works have been expressed. This case was examined in two case studies from different perspectives. The first one was to study the implications on project appraisal and the second one examined the possibility to optimise pavement design. Results from cost benefit analyses based on established road appraisal techniques indicated that operation and maintenance related costs had limited impact on profitability. The second study also indicated that future cost can be influenced differently depending on criteria for optimal alternative. Based on economic analyses using established techniques, increased operation and maintenance liabilities appear to be of limited concern, in contrary to the perception. In future research this need to be set in context of road management with refined analysis in order to study implications for future management. / <p>QC 20141028</p>

Achieving a sustainable production has become more important in the same phase as the environmental focus grows. Sustainable production means that you take into consideration the economical and environmental life cycle, that can be analyzed and measured with help from LCC (Life Cycle Cost) and LCA (Life Cycle Assessment). The purpose of this study has been to increase the understanding for how LCC and LCA can be used in order to improve the economical and environmental sustainability within manufacturing processes. The goal has been to identify weaknesses and improvement potential in order to strengthen sustainability. There has also been a purpose to create a template with the purpose to promote other companies to identify which factors need to be improved. Data has been collected through structured interviews and other documents from the studied company. Results and conclusions present that the studied company’s production is economically and environmentally sustainable but there is room for improvement.  The improvement suggestions that the authors have come up with is following: - Reduce costs by improving the flow within the production - Shorten the distance of transportation by choosing local suppliers - Choosing more environmentally friendly transportation. / Att uppnå en hållbar produktion är någonting som blir viktigare och viktigare med de ökade miljökrav som ställs. Hållbar produktion innebär att man tar hänsyn till den ekonomiska och miljömässiga livscykeln, som kan analyseras och mätas med hjälp av LCC (Life Cycle Costs) och LCA (Life Cycle Assessment).  Syftet med denna studie har varit att ge en ökad förståelse för hur LCC och LCA kan användas för att förbättra den ekonomiska och miljömässiga hållbarheten inom produktioner. Målet med studien har varit att identifiera svagheter och förbättringspotential inom produktionsprocesser för att stärka hållbarheten. Det har även funnits ett syfte att skapa en mall med syfte att främja andra företag att identifiera vilka faktorer som behöver förbättras. Data har samlats in genom strukturerade intervjuer och annan dokumentation från det studerade fallföretaget. Resultat och slutsats presenterar att företagets produktion är ekonomiskt och miljömässigt hållbart men att förbättringspotential finns. De förbättringsförslag som författarna kom fram till var följande: - Reducera kostnader genom att förbättra flödet - Minska transportsträckan genom lokala leverantörer - Välja miljövänligare transport / <p>Digital presentation som följd av Covid-19.</p>

growing concern on achieving environmental sustainability and at the same time making economical savings has become a necessity in our society. The prices of different battery energy storage technologies together with PV cells are declining all around the globe which has led to the fact that there is an increased interest in investing and using these technologies to be able to reach environmental sustainability. The combined system however, must be accurately calculated both when it comes to the sizing and the different costs related to the combined system to be able to make an economical saving. This thesis addresses both of those aspects in Sweden where a residential building with roof-top installed PV system is assessed with a battery energy storage system. An investigation is necessary to be able to assess the different battery storage technologies available in the market today with their specific technical and economical specifications. The electricity market in Sweden, the role of the Distribution System Operator on the electricity pricing with different time tariffs and fuse size subscription, PV generation and battery specifications are investigated and modeled in this study. Sizing of the different battery technologies for the given system is accomplished through a methodology that is developed in this project for the Swedish system. The calculated size of the battery is then used in the Life Cycle Cost analysis, using Monte Carlo simulations for a chosen period of 25 years.Calculations shows that the most appropriate size for the battery system with the given parameters is 6 kWh for all the battery types investigated in this study. The size of the batteries is also shown to be mainly dependent on the charging/discharging time together with the set fuse size margin. Profitability of the Battery Energy Storage system is proven to be mainly dependent on the fuse size downgrade. Sulphur-Sodium battery result in the greatest savings while Vanadium Redox batteries in the least when sizing the batteries. Lithium-Ion battery technology however is most likely to result in the lowest Levelized Cost of Electricity, total- and cycle costs while the highest Net Present Value with 90 % probability in the Monte Carlo simulations. Lithium-Ion battery technology is also found to have the highest probability of having a positive NPV compared to the lowest probability for Sulphur-Sodium battery technology. Lead-Acid battery technology is however shown to have the least uncertainties compared to other Battery Energy Storage technologies due to its maturity. It is additionally shown that government subsidy plays a crucial role when investing in the battery storage system. However, even with the case of removed government subsidy, Lithium-Ion battery technology still results in the largest probability of having a positive NPV while Sulphur-Sodium battery technology results in the lowest probability of having a positive NPV. / Den växande oron för att uppnå miljömässig hållbarhet och samtidigt göra ekonomiska besparingar har blivit en nödvändighet i vårt samhälle. Priserna på olika energilagrings teknologier så som batterier tillsammans med PV-celler minskar runt om i världen vilket har lett till att det finns ett ökat intresse när det gäller att investera och använda dessa teknologier för att kunna nå miljömässig hållbarhet. Det kombinerade systemet måste dock noggrant beräknas både när det gäller storleken och de olika kostnaderna för det kombinerade systemet för att kunna göra en ekonomisk besparing. Denna avhandling behandlar båda dessa aspekter i Sverige där en bostadsbyggnad med takmonterat PV system utvärderas med ett batteri system. En undersökning är nödvändig för att kunna bedöma de olika batteri teknologier som finns tillgängliga på marknaden idag med sina specifika tekniska och ekonomiska specifikationer. Elmarknaden i Sverige, Distribution System Operatörs roll för elprissättning med olika tidstariffer och säkringsabonnemang, PV-generation och batterispecifikationer undersöks och modelleras i denna studie. Dimensionering av olika batteri teknologier för det givna systemet uppnås genom en metod som utvecklats i detta projekt för det svenska systemet. Den beräknade storleken på batteriet används sedan i livscykelkostnadsanalysen, med Monte Carlo-simuleringar under en vald period på 25 år. Beräkningar visar att den optimala storleken för batterisystemet med de angivna parametrarna är 6 kWh för alla batterityper som undersöktes i denna studie. Batteriets storlek visar sig också vara huvudsakligen beroende av laddning / urladdningstiden tillsammans med den inställda säkrings storleken. Lönsamheten hos batterilagringssystemet visar sig vara huvudsakligen beroende av säkringens nedgradering. Svavel-Natriumbatteriet resulterar i de största besparingarna medan Vanadium Redox batteriet i de minsta när dimensionering av batteriet äger rum. Litium-Ion batteriet är emellertid sannolikt att leda till den lägsta nivån av elkostnader, total- och cykelkostnader, medan det högsta nettoförsäljningsvärdet med 90% sannolikhet i Monte Carlo-simuleringarna. Litium-Ion batteriet befanns också ha den högsta sannolikheten att ha en positiv NPV jämfört med Svavel-Natriumbatteriet som resulterar i den lägsta sannolikheten. Lead-Acid batteriet visar sig ha den minsta osäkerheten i jämförelse med andra batterilagrings teknologier på grund av dess mognad. Det framgår dessutom att statlig subvention spelar en avgörande roll när man investerar i ett batteri lagrings system. Dock även med borttagna statliga subventioner, resulterar Litium-Ion batteriet fortfarande största sannolikheten för att ha en positiv NPV, medan Svavel-Natriumbatteriet resulterar den lägsta sannolikheten för att ha en positiv NPV.