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  • Open Access English
    Authors: 
    Lähdeaho, Oskari;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Sustainability has emerged as a central concern in business. Across all sectors, companies are looking for ways to reduce their negative environmental impact. Globally, transportation accounts for approximately a quarter of all produced carbon dioxide emissions. At the same time, companies are reliant on logistics and supply chains to function. Amid these concerns, companies are also recognizing opportunities to improve their competitiveness through embracing sustainability. Therefore, logistics operations can be seen as a major component of business operations that require radical changes in order to improve environmental sustainability. This doctoral thesis aims to explore ways for logistics industries to benefit from ongoing sustainability transitions. The main research strategy for this thesis is to carry out qualitative case studies, which are mixed with quantitative survey method, and supported by analytical and bibliometric studies. This mixed approach strengthens the exploratory nature of this research work. As exploration seldom has a clear or defined expected result, these approaches on their part structure the detailed results. Data triangulation with these methods allows close examination of novel phenomena in logistics industries as they unfold. These phenomena are often complex, and singular approaches give a narrow view on them. As the topics of this research are still developing, the exploratory nature offers a way to make necessary appendments to the existing theories in logistics and sustainability. The results of this thesis have been published in seven scientific articles, of which six are published in peer-reviewed scientific journals, and one is published in conference proceedings. Publication I explores business models in changing regulative and business environment. Publication II studies the case of environmental sustainability in a setting of a port and companies operating in that port. Publication III examines the development of road transport emissions development in Finnish setting. Publications IV and V study how logistics and manufacturing companies are surviving amid the Covid-19 pandemic and its implications. Publication VI is bibliometric research aimed at studying the development of scientific literature on the interplay of sustainability and innovation. Lastly, Publication VII examines logistics companies’ environmental performance and ability to self-assess in this regard. This research work showcases the emergence of sustainability as an important factor for competitiveness in the logistics industries. While some have been adapting to this change already, most are lagging. Most of the studied companies can comply with baseline regulation for now but lack the proactivity to appeal to stakeholder demands and struggle with stricter future regulations. Smaller companies especially are left in an uncomfortable situation with tightening regulations, while other events (e.g., Covid-19 and economic sanctions) are increasing the uncertainty in the studied industries. As modern societies are dependent on smaller companies acting as sub-contractors for larger enterprises, commonly beneficial solutions and policies must be found to ensure sustainability in these societies. This research work studies companies with a close case study lens with an aim to better understand the larger networks these companies form. As both logistics and sustainability are complex topics, this type of study is needed to understand the nuances and inner workings of logistics networks in relation to sustainability efforts.

  • Open Access English
    Authors: 
    Ryynänen, Marko;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Businesses need to secure the continuity of their operations also in unforeseen events, where severe market disturbances are present. Risk assessments, including cost forecasting analyses, are needed to identify different types of risks in order to mitigate them. Furthermore, the carbon footprint of raw materials, production processes and products should be minimized, driven by the tightening legislation aiming to minimize climate change. The efforts needed can sometimes be costly e.g. regarding the modernization of existing production technology. However, these kinds of investments can be justified in enabling the utilization of renewable, recyclable materials and the minimization of waste streams. The objective of this doctoral dissertation is to describe how the calculation model being created by the author (A forecasting model of packaging cost, or FMPC) is suited for forecasting packaging costs within value chains in such above-mentioned situations. The cigarette packaging value chain has been selected for the case study; the functionality of the model has been demonstrated with certain scenarios focusing on the influences of the plain packaging legislation, which was first taken into use in Australia in 2012. The Design Science Research (DSR) methodology has been followed when designing, developing, and evaluating the FMPC. Even though the case study focuses on cigarette packaging, the FMPC has been created in a way that it can also be utilized for evaluating other types of packaging production processes and value chains, increasing its theoretical value. The empirical results illustrated in the scenarios are descriptive in nature as a reallife production test arrangement-based evaluation is also needed. The design principles of the extended FMPC follow the same guidelines used in the earlier version of the model as its evaluation has been validated in the industry. The results of the research illustrate the advantages of the FMPC in increasing knowledge regarding the cost structures of the packaging value chains and in making the required risk assessments to support business decisions. Furthermore, by utilizing the output data, it becomes possible to forecast the carbon footprint of the selected production processes and raw materials enabling possibilities for minimizing their environmental load and related costs.

  • Open Access English
    Authors: 
    Lipiäinen, Satu;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    The forest industry has increased its energy efficiency substantially in the 21st century, but higher improvement rates could be expected regarding targets set by the European Union and the Intergovernmental Panel on Climate Change. A variety of factors, i.e. technology development, structural changes and climate policies can drive energy efficiency improvement and decarbonization. This thesis looks how the Finnish and Swedish forest industries are developing towards energy efficient and low-carbon operation and evaluates the role of the sector in mitigating global change. These countries have long been forerunners in efficient operation and the decarbonization of the sector. The dependency on fossil fuels has decreased in the forest industry as energy efficiency has improved and fossil fuel use has been switching to biofuels. Potential opportunities to reduce CO2 emissions substantially exist: the Finnish and Swedish pulp mills have managed to operate lime kilns using a wide range of biofuels and their recovery boilers have been developed to produce significantly more renewable electricity and heat. New operating modes such as polysulphide cooking seem to provide a cost-effective way to produce pulp with higher material efficiency, but new solutions often cause changes in energy consumption and production. Structural changes, for example start-ups and closures of mills, have had a limited effect on energy efficiency improvement, which highlights the importance of maintaining efficient operation in existing mills. The forest industry can play a significant role in mitigating global change. The production of bioenergy and biofuels can be increased, notable energy savings can be expected and at least in comparison to other industrial sectors, the forest industry has good premises to achieve net zero industrial emissions before 2050. However, even though the forest industry has developed towards more sustainable operation and feasible technologies for improvement exist, the pace of evolution is slow in light of the urgent targets to mitigate global warming. The forest industry is the fourth largest industrial energy user and the fifth largest fossil CO2 emitter in the world. Investment cycles are long in the forest industry, and 2050 is only one cycle away. Thus, more research and political guidance are needed immediately to accelerate the evolution worldwide.

  • Open Access English
    Authors: 
    Araya Gómez, Natalia Andrea;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    The mining industry consumes water and energy to produce a metal or mineral product from mineral resources on the earth’s crust, leaving enormous waste. The main waste produced by the mining industry is mine tailings, which generally consist of a slurry containing water and reagents used in the processes and crushed ore. Tailings are usually stored in dams that can threaten the environment since they can pollute soil, water bodies and nearby communities. Water is used in most mining processes, as well as in the management of tailings. Since most mines are located in arid zones, reducing water consumption is crucial for the efficient use of water resources. The mining industry has improved water and energy efficiency and strengthened tailings disposal. Nevertheless, considerable effort is still needed to ensure the sustainable development of the mining sector. This dissertation aims to develop methods and tools to advance sustainable development in mining, focusing on water and tailings management. The strategies and tools proposed can be applied in mining processes to mitigate environmental impacts and enable the sustainable development of this industry. Methods used in this dissertation include mathematical optimisation, economic valuation methods and sensitivity and uncertainty analyses. To improve water management for mining companies, we proposed a method to supply water to several mine sites with the option of producing energy in the network. Another contribution was a framework to improve the water-energy nexus in mine sites, focusing on tailings disposal technologies. The methods used to accomplish this goal were a water reduction model, real options approach, and sensitivity and uncertainty analyses. Results show that an integrated system to supply water for mining companies, including energy production in the network, can be cheaper than an independent supply for each company. Moreover, dewatering technologies for tailings will reduce the water requirement to the mine site, reducing overall costs and reducing energy consumption in water transport and treatment. To improve mine tailings management, besides the use of dewatering technologies to recover water, the reprocessing of tailings is proposed to recover critical raw materials (CRMs) since some tailings contain quantities of them. A framework is applied, that includes quantifying CRMs in tailings, economic assessment using the discounted cash flow (DCF) method, and a real options approach with sensitivity and uncertainty analyses. Results show that tailings have quantities of CRMs. Tailings can be a secondary source of these materials in the future, under the right conditions of capital expenditure, operating expenditure and prices. This dissertation provides a collection of methods to improve tailings and water management in mining. This study’s novelty consists of considering both water and tailings to enhance the management of tailings and water supply to mine companies by considering the energy component of water treatment, transport and water used in tailings disposal. In addition, the possibility of obtaining CRMs from tailings is studied using an economic approach that introduces real options analysis to complement traditional valuation tools. The importance of this dissertation relies on proposing methods and tools to guide mining towards more sustainable water and tailings management that includes recovery of water and CRMs from tailings.

  • Open Access English
    Authors: 
    Ramírez Angel, Yendery;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Water and energy use are intrinsically intertwined and are critical factors influencing mining sustainability. The rising demand for metals and the decrease of ore grade cause the increase of water volume required and the waste amount generated. Moreover, the reprocessing of mine tailings for the recovery of valuable materials trigger consumption of water and energy. All those factors are a threat to sustainability. The water-energy nexus in the mining industry has a significant impact on sustainability since decreasing waste by reusing, recycling, and reducing the water and energy consumption. Therefore, urge the need for suitable management of water and energy use that lead the way for sustainable mining industry in the context of the circular economy to attain the rising problems. The dissertation aims to provide an insight into the decision-making process to ensure the sustainable operation of mining processes and the related reprocessing of production waste. It is obtained through a comprehensive assessment of technological, environmental, and economic aspects of the operations concerned. The water-energy nexus analysis is applied through the development of frameworks to facilitate and support the decision-making process of stakeholders, to improve the water and waste management in the mining industry that leads to a sustainable circular economy. The main outputs of the dissertation are: The technology assessment provides an insight to decision-makers to aid them to improve technologies so that they can meet specific customers’ demands; The environmental assessment offers a straightforward and fast analysis of the energy consumption influence in water treatment and distribution systems and its effect onto the environment, considering water distribution systems, water quality, and how energy affects these variables; The economic assessment of the feasibility of reprocessing mining tailings to recover critical raw materials, considering the uncertainties involved; and the water-energy nexus assessment on tailings facilities to found and optimised the trade-offs between water and energy. Therefore, obtaining the guidance for proper mine tailings and water management in the mining industry.

  • Open Access English
    Authors: 
    Ram, Manish;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    There are undeniable signs from all over the world demonstrating that climate change is already upon us. Numerous scientific studies have warned of dire consequences should humankind fail to keep average global temperatures from rising beyond 1.5°C. Drastic measures to eliminate greenhouse gas emissions from all economic activities across the world are essential. Major emphasis has been on the energy sector, which contributes the bulk of GHG emissions. Inevitably, energy scenarios describing future transition pathways towards low, and zero emissions energy systems are commonly proposed as mitigation strategies. However, there is growing awareness in the research community that energy transitions should be understood and analysed not only from technical and economical perspectives but also from a social perspective. This research explores the broader ramifications of a global energy transition from various dimensions: costs and externalities of energy production, democratisation of future energy systems and the role of prosumers, employment creation during energy transitions at the global, regional and national levels and the effects of air pollution during energy transitions across the world. This research builds on fundamental techno-economic principles of energy systems and relies firmly on a cost driven rationale for determining cost optimal energy system transition pathways. Techno-economic analyses of energy transitions around the world are executed with the LUT Energy System Transition Model, while the corresponding socioeconomic aspects are expressed in terms of levelised cost of electricity, cost effective development of prosumers, job creation, and the reduction of greenhouse gas emissions along with air pollution. Findings during the course of this original research involved novel assessments of the levelised cost of electricity encompassing externalities across G20 countries, cost optimal prosumer modelling across the world, estimates of job creation potential of various renewables, storage and power-to-X technologies including the production of green hydrogen and e-fuels during global, regional and national energy transitions. The novel research methods and insights are published in several articles and presented in this thesis, which highlight robust socioeconomic benefits of transitioning the current fossil fuels dominated global energy system towards renewables complemented by storage and flexible power-to-X solutions, resulting in near zero emissions of greenhouse gases and air pollutants. These research findings and insights have significant relevance to stakeholders across the energy landscape and present a compelling case for the rapid transformation of energy systems across the world. However, the research does have limitations and is based on energy transition pathways that are inherent with uncertainties and some socioeconomic challenges. Nonetheless, actions to enhance and accelerate the ongoing energy transition across the world must be prioritised, if not for technical feasibility or economic viability, but for the social wellbeing of human society and future generations.

  • Open Access English
    Authors: 
    Qorri, Ardian;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Supply chains are the backbone behind companies. Integrating sustainability in supply chains is difficult but essential to gain competitive advantages. While sustainability recognizes the interdependence of environmental, social, and economic aspects, measuring and managing performance across chain partners is challenging. The information generated from measurement process is used by management to control, communicate, and improve their efforts and relationships with partners. Hence, supply chain sustainability measurement and management are critical in achieving firm’s strategic objectives. However, existing performance measurement and management tools fail to consider all sustainability aspects across supply chain practices and partners. The goal of this dissertation is to explore and develop approaches for measuring and managing sustainability performance of supply chains. By applying a mixed methodology including a systematic literature review, conceptual design, content analysis, metaanalysis, fuzzy Entropy, fuzzy TOPSIS, and sensitivity analysis, I develop a novel and practical method to measure and manage sustainability performance in supply chains. The results of this dissertation have been published in four articles, for which the data was gathered through several sources. The results show (i) the state of the art of sustainability performance measurement approaches; (ii) the proposed conceptual framework explains new relationships between sustainability performance measurement components and stakeholders; (iii) the effect of social and environmental supply practices on firm performance; and (iv) sensitivity analysis confirm that the proposed measurement approach is practical and generates robust and usable outcomes. The dissertation contributes to the literature by providing new insights for scholars, managers, policymakers, and other stakeholders regarding environmental and social supply practices for achieving sustainable development.

  • Open Access English
    Authors: 
    Koskinen, Pilvi;
    Country: Finland

    In recent years, the growth of environmental and climate awareness has been strongly reflected in global politics. The pressure to bring food packaging into line with sustainability is a topical matter influencing society. This master's thesis examines the media debate on the sustainability of food packaging in the Finnish news media. From a sample of three Finnish newspapers classified as high-quality from January 2010 to December 2020, the author of this master's thesis identified news articles on food packaging sustainability based on certain criteria. The analyses looked at the variety of different themes that were addressed in the debate on the sustainability of food packaging in newspapers, and what innovations were proposed for the sustainability transition of food packaging. There were 216 ‘food packaging’ news articles in these newspapers during this period. These news articles were divided into eleven main themes based on their essential content. The themes identified were business solutions and innovations, plastic separating, collecting, recycling, reusing, and reducing, recycling enthusiasm and problems at the consumer, municipal, and state levels, laws and regulations, marine litter and micro-plastics, food safety, issues with plastic substitutes, energy waste, over-packaging, plastics industry, and food waste. Some of the themes appeared in the data more and some less. Of the news articles, 31% mentioned innovations. The majority of the innovations were considering new innovative materials for replacing fossil-based plastics from food packaging. The three main materials mentioned were bioplastic, cardboard, and wood. Both cardboard and bioplastic were mainly wood-based in the research material. The number of food packaging news articles and proposed innovations both peaked in 2018. The coverage of food packaging and the different themes in Finnish newspapers from the perspective of sustainability and sustainability transitions increased considerably during the research period. Based on mitigating the effects of climate change while maintaining food security, the choice of food packaging materials will play an increasingly important role in the future. Viime vuosien ympäristö- ja ilmastotietoisuuden kasvu on heijastunut voimakkaasti globaaliin politiikkaan. Elintarvikepakkausalan kestävyysmuutokset ovat ajankohtainen ja yhteiskunnassa laajalti vaikuttava asia. Tässä pro gradu -työssä tarkastellaan elintarvikepakkausten kestävyydestä käytävää mediakeskustelua suomalaisessa uutismediassa. Pro gradu -työn tekijä tunnisti elintarvikepakkauksia koskevia artikkeleita tiettyjen kriteerien perusteella kolmen laadukkaaksi luokitellun suomalaisen sanomalehden otoksesta. Tutkimusjakso oli tammikuusta 2010 joulukuuhun 2020. Analyysissa tarkasteltiin elintarvikepakkausten kestävyyden teemoja sekä sitä, millaisia innovaatioita elintarvikepakkausten kestävyyssiirtymään mainittiin näissä sanomalehdissä. Sanomalehdistä löytyi tarkasteluajanjakson ajalta 216 uutisartikkelia, jotka käsittelivät elintarvikepakkauksia kestävän kehityksen ja kestävyysmuutosten näkökulmasta. Nämä uutisartikkelit jaettiin yhteentoista pääteemaan olennaisen sisällön perusteella. Löydettyjä teemoja olivat liiketoiminnalliset ratkaisut ja innovaatiot, muovien erottelu, keräys, kierrätys, uusiokäyttö ja käytön vähentäminen, innostus ja ongelmat liittyen kierrätykseen, lait ja määräykset, meriroska ja mikromuovit, elintarviketurvallisuus, muovinkorvikkeiden ongelmat, energiajae ja jätteiden poltto, ylipakkaaminen, yrittäjyys muovialalla, ja ruokahävikki. Osa teemoista toisia sai laajempaa mediahuomiota. Uutisartikkeleista 31 %:ssa mainittiin innovaatiot. Suurin osa innovaatioista koski uusia materiaaleja fossiilipohjaisen muovin korvaamiseksi elintarvikepakkauksista. Kolme korvaamiseen ehdotettua päämateriaalia olivat biomuovi, kartonki ja puupohjaiset materiaalit. Sekä kartonki että biomuovi olivat tässä aineistossa pääasiassa puupohjaisia. Sekä uutisartikkelien, että ehdotettujen innovaatioiden määrä saavutti huippunsa vuonna 2018. Elintarvikepakkausten uutiskattavuus suomalaisissa sanomalehdissä kestävyysajattelun ja kestävyysmuutosten näkökulmasta kasvoi merkittävästi tutkimusjakson aikana. Asiaa koskevat teemat lisääntyivät ja laajenivat tutkimusvuosien aikana. Ilmastonmuutoksen vaikutusten lieventämiseen ja elintarviketurvan säilyttämiseen perustuen elintarvikkeiden pakkausmateriaalien valinnalla on tulevaisuudessa yhä tärkeämpi rooli.

  • Open Access English
    Authors: 
    Laine, Aki;
    Country: Finland

    This bachelor’s thesis examines the sustainability effects of utilizing cloud and edge computing in the manufacturing industry. Additionally, the concept of edge cloud computing and its benefits are presented. The topic is examined by analyzing the sustainability of cloud and edge computing solutions and their use cases in manufacturing. The research is conducted as a literature review and industry published material is also used to understand market needs for these technologies. The results indicate that utilizing cloud and edge computing in manufacturing for purposes such as data analysis, automation, and interorganizational collaboration can offer significant sustainability improvements. These include better resource and energy efficiency, improved productivity, safety, quality, flexibility, and scalability. Cost savings and reductions in waste and downtime can also be achieved. Research shows that cloud computing is more sustainable and energy efficient than its alternative, localized servers. Edge computing solutions offer lower latency compared to centralized data centers. Furthermore, edge computing enables savings in energy consumption and costs by reducing the amount of required data transportation. Decentralizing cloud resources into edge cloud data centers offers computing capabilities with low latency. This allows hosting latency critical applications that exceed the computing capacity of edge devices. Furthermore, edge cloud data centers can enable significant energy and cost savings for applications that are not compute-intensive. Latency tolerant compute-intensive applications should be hosted in larger centralized data centers with higher energy efficiency and processing capacity. Tässä kandidaatintyössä tutkitaan pilvi- ja reunalaskennan hyödyntämisen kestävyysvaikutuksia valmistavassa teollisuudessa. Lisäksi esitellään, mitä reunapilvilaskenta tarkoittaa ja millaisia hyötyjä sillä voidaan saavuttaa. Työssä tarkastellaan pilvi- ja reunalaskentaratkaisujen kestävyystekijöitä sekä valmistavan teollisuuden käyttötapauksia. Tutkimus on toteutettu kirjallisuuskatsauksena. Myös yritysten julkaisemaa materiaalia on hyödynnetty teknologioiden markkinatarpeiden ymmärtämiseksi. Tulokset osoittavat, että valmistavassa teollisuudessa voidaan saavuttaa merkittäviä kestävyyshyötyjä käyttämällä pilvi- ja reunalaskentaa data-analyysissa, automaatiossa ja organisaatioiden välisen yhteistyön edistämisessä. Näitä hyötyjä ovat parempi resurssi- ja energiatehokkuus, korkeampi tuottavuus, turvallisuus, laatu, joustavuus ja skaalautuvuus. Teknologioiden hyödyntäminen mahdollistaa myös hävikin ja häiriöiden vähentämisen sekä tuo kustannussäästöjä. Pilvilaskennan voidaan todeta olevan ympäristöystävällisempi ja kustannustehokkaampi vaihtoehto kuin paikallisten palvelimien käyttäminen. Reunalaskentaratkaisut tarjoavat lyhyemmän viiveen kuin keskitetyt datakeskukset. Lisäksi reunalaskenta vähentää datansiirron tarvetta, mikä mahdollistaa energiasäästöjä. Pilviresurssien hajauttaminen reunapilvidatakeskuksiin tarjoaa laskentakapasiteettia lyhyellä viiveellä. Tämä mahdollistaa reunalaitteiden laskentakapasiteetin ylittävien viivekriittisten sovellusten tarjoamisen. Reunapilvidatakeskuksilla voidaan myös saavuttaa huomattavia kustannus- ja energiasäästöjä sovelluksissa, jotka eivät vaadi suurta prosessointitehoa. Sovellukset, jotka vaativat suuren prosessointitehon ja kestävät viivettä, kannattaa pitää suuremmissa keskitetyissä datakeskuksissa.

  • Open Access Finnish
    Authors: 
    Lindholm, Kimmo;
    Country: Finland

    Sähkönjakeluverkon haltijan pitää varautua normaaliolojen häiriötilanteisiin sekä valmiuslaissa tarkoitettuihin poikkeusoloihin. Normaaliolojen häiriötilanteissa ja poikkeusoloissa, kun yleinen sähkönjakelu on keskeytynyt, tarvitaan varatuotantojärjestelmiä, jotta keskeytyskriittistä toimintaa voidaan jatkaa yleisestä sähköverkosta erotetussa saarekkeessa. Normaalioloissa osaa sähköenergian varatuotantolaitteistoista voidaan käyttää uusiutuvan sähköenergian lähteinä. Sähkönjakeluverkon haltijan on huolehdittava jakeluverkon sähköturvallisuudesta ja suojausten toimivuudesta kaikissa käyttötilanteissa ja olosuhteissa. Tässä opinnäytetyössä tarkastellaan varatuotantojärjestelmiä, jotka liitetään valmiiseen olemassa olevaan sähkönjakeluverkkoon. Tällöin erityisesti saarekekäyttö asettaa tuotantolaitteistolle tiettyjä vaatimuksia, jotta sähköturvallisuus ja suojaukset pysyvät vaaditulla tasolla. Tässä opinnäytetyössä tarkastellaan sähköenergian tuotantolaitteistojen ominaisuuksia, jotka pitää ottaa huomioon suunnittelussa ja tuotantolaitteistojen valinnassa. Tarkasteltavat tuotantolaitteistot ovat diesel-varavoimakone, aurinkosähkövoimala ja akkuenergiavarasto. Opinnäytetyössä havaitaan, että ylivirta- ja vikasuojauksen toimivuuden kannalta olennaisin ominaisuus on tuotantolaitteiston virransyöttökyky erityisesti oikosulussa. Virransyöttökykyä vaaditaan vikatilanteessa oikosulussa olevan sähkönjakeluverkon osan suojalaitteen toimimiseksi. Tuotantolaitteiston on pystyttävä tuottamaan riittävä oikosulkuvirta myös sähkönjakelujärjestelmän kauimmaisiin ja epäedullisimpiin kohtiin. Tarkasteltujen sähköenergian tuotantolaitteistojen virransyöttökyky poikkeaa olennaisesti toisistaan. Tuotantolaitteiston keskijänniteverkon yli syöttämää vikavirtaa ei voida pienjänniteverkossa sähköasennustesterillä mittaamalla todentaa, kuten yleisen sähköverkon syöttäessä vikavirtaa, vaan siihen tarvitaan verkostolaskentaa. Opinnäytetyössä esitellään laskentamenetelmät ja tarkastellaan ylivirta- ja vikasuojauksen toteutuminen erään kohteen osalta. The operator of the electricity distribution system must be prepared for disruptions to normal conditions as well as exceptional conditions referred to in the emergency act. In the event of disruptions to normal conditions and exceptional conditions, when the general electricity distribution has been interrupted, backup production systems are needed so that interruption-critical operations can be continued in an island separated from the general electricity grid. Under normal conditions, part of the backup electricity production system can be used as sources of renewable electrical energy, in which case the production corresponds to small-scale production according to the definition of the electricity market act, if it falls below the specified power limit. The owner of the electricity distribution network must take care of the electrical safety of the distribution network and the functionality of the protections in all operating situations and conditions. This thesis examines back-up production systems that are connected to a ready-made existing electricity distribution network. In this case, island operation in particular places certain requirements on production systems, so that electrical safety and protections remain at the required level. The thesis examines the characteristics of electrical energy production systems, which must be taken into account in the design and selection of production systems. The production systems under consideration are a diesel back-up generator, a solar power plant and a battery energy storage. In the thesis, it is found that the most essential feature in terms of the functionality of overcurrent and fault protection is the current supply capability of the production system, especially in the event of a short circuit. The production system must be able to produce sufficient short-circuit current even to the farthest and most unfavorable parts of the electricity distribution system. The current supply capacity of the examined electrical energy production systems differs substantially from one another.

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491 Research products, page 1 of 50
  • Open Access English
    Authors: 
    Lähdeaho, Oskari;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Sustainability has emerged as a central concern in business. Across all sectors, companies are looking for ways to reduce their negative environmental impact. Globally, transportation accounts for approximately a quarter of all produced carbon dioxide emissions. At the same time, companies are reliant on logistics and supply chains to function. Amid these concerns, companies are also recognizing opportunities to improve their competitiveness through embracing sustainability. Therefore, logistics operations can be seen as a major component of business operations that require radical changes in order to improve environmental sustainability. This doctoral thesis aims to explore ways for logistics industries to benefit from ongoing sustainability transitions. The main research strategy for this thesis is to carry out qualitative case studies, which are mixed with quantitative survey method, and supported by analytical and bibliometric studies. This mixed approach strengthens the exploratory nature of this research work. As exploration seldom has a clear or defined expected result, these approaches on their part structure the detailed results. Data triangulation with these methods allows close examination of novel phenomena in logistics industries as they unfold. These phenomena are often complex, and singular approaches give a narrow view on them. As the topics of this research are still developing, the exploratory nature offers a way to make necessary appendments to the existing theories in logistics and sustainability. The results of this thesis have been published in seven scientific articles, of which six are published in peer-reviewed scientific journals, and one is published in conference proceedings. Publication I explores business models in changing regulative and business environment. Publication II studies the case of environmental sustainability in a setting of a port and companies operating in that port. Publication III examines the development of road transport emissions development in Finnish setting. Publications IV and V study how logistics and manufacturing companies are surviving amid the Covid-19 pandemic and its implications. Publication VI is bibliometric research aimed at studying the development of scientific literature on the interplay of sustainability and innovation. Lastly, Publication VII examines logistics companies’ environmental performance and ability to self-assess in this regard. This research work showcases the emergence of sustainability as an important factor for competitiveness in the logistics industries. While some have been adapting to this change already, most are lagging. Most of the studied companies can comply with baseline regulation for now but lack the proactivity to appeal to stakeholder demands and struggle with stricter future regulations. Smaller companies especially are left in an uncomfortable situation with tightening regulations, while other events (e.g., Covid-19 and economic sanctions) are increasing the uncertainty in the studied industries. As modern societies are dependent on smaller companies acting as sub-contractors for larger enterprises, commonly beneficial solutions and policies must be found to ensure sustainability in these societies. This research work studies companies with a close case study lens with an aim to better understand the larger networks these companies form. As both logistics and sustainability are complex topics, this type of study is needed to understand the nuances and inner workings of logistics networks in relation to sustainability efforts.

  • Open Access English
    Authors: 
    Ryynänen, Marko;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Businesses need to secure the continuity of their operations also in unforeseen events, where severe market disturbances are present. Risk assessments, including cost forecasting analyses, are needed to identify different types of risks in order to mitigate them. Furthermore, the carbon footprint of raw materials, production processes and products should be minimized, driven by the tightening legislation aiming to minimize climate change. The efforts needed can sometimes be costly e.g. regarding the modernization of existing production technology. However, these kinds of investments can be justified in enabling the utilization of renewable, recyclable materials and the minimization of waste streams. The objective of this doctoral dissertation is to describe how the calculation model being created by the author (A forecasting model of packaging cost, or FMPC) is suited for forecasting packaging costs within value chains in such above-mentioned situations. The cigarette packaging value chain has been selected for the case study; the functionality of the model has been demonstrated with certain scenarios focusing on the influences of the plain packaging legislation, which was first taken into use in Australia in 2012. The Design Science Research (DSR) methodology has been followed when designing, developing, and evaluating the FMPC. Even though the case study focuses on cigarette packaging, the FMPC has been created in a way that it can also be utilized for evaluating other types of packaging production processes and value chains, increasing its theoretical value. The empirical results illustrated in the scenarios are descriptive in nature as a reallife production test arrangement-based evaluation is also needed. The design principles of the extended FMPC follow the same guidelines used in the earlier version of the model as its evaluation has been validated in the industry. The results of the research illustrate the advantages of the FMPC in increasing knowledge regarding the cost structures of the packaging value chains and in making the required risk assessments to support business decisions. Furthermore, by utilizing the output data, it becomes possible to forecast the carbon footprint of the selected production processes and raw materials enabling possibilities for minimizing their environmental load and related costs.

  • Open Access English
    Authors: 
    Lipiäinen, Satu;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    The forest industry has increased its energy efficiency substantially in the 21st century, but higher improvement rates could be expected regarding targets set by the European Union and the Intergovernmental Panel on Climate Change. A variety of factors, i.e. technology development, structural changes and climate policies can drive energy efficiency improvement and decarbonization. This thesis looks how the Finnish and Swedish forest industries are developing towards energy efficient and low-carbon operation and evaluates the role of the sector in mitigating global change. These countries have long been forerunners in efficient operation and the decarbonization of the sector. The dependency on fossil fuels has decreased in the forest industry as energy efficiency has improved and fossil fuel use has been switching to biofuels. Potential opportunities to reduce CO2 emissions substantially exist: the Finnish and Swedish pulp mills have managed to operate lime kilns using a wide range of biofuels and their recovery boilers have been developed to produce significantly more renewable electricity and heat. New operating modes such as polysulphide cooking seem to provide a cost-effective way to produce pulp with higher material efficiency, but new solutions often cause changes in energy consumption and production. Structural changes, for example start-ups and closures of mills, have had a limited effect on energy efficiency improvement, which highlights the importance of maintaining efficient operation in existing mills. The forest industry can play a significant role in mitigating global change. The production of bioenergy and biofuels can be increased, notable energy savings can be expected and at least in comparison to other industrial sectors, the forest industry has good premises to achieve net zero industrial emissions before 2050. However, even though the forest industry has developed towards more sustainable operation and feasible technologies for improvement exist, the pace of evolution is slow in light of the urgent targets to mitigate global warming. The forest industry is the fourth largest industrial energy user and the fifth largest fossil CO2 emitter in the world. Investment cycles are long in the forest industry, and 2050 is only one cycle away. Thus, more research and political guidance are needed immediately to accelerate the evolution worldwide.

  • Open Access English
    Authors: 
    Araya Gómez, Natalia Andrea;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    The mining industry consumes water and energy to produce a metal or mineral product from mineral resources on the earth’s crust, leaving enormous waste. The main waste produced by the mining industry is mine tailings, which generally consist of a slurry containing water and reagents used in the processes and crushed ore. Tailings are usually stored in dams that can threaten the environment since they can pollute soil, water bodies and nearby communities. Water is used in most mining processes, as well as in the management of tailings. Since most mines are located in arid zones, reducing water consumption is crucial for the efficient use of water resources. The mining industry has improved water and energy efficiency and strengthened tailings disposal. Nevertheless, considerable effort is still needed to ensure the sustainable development of the mining sector. This dissertation aims to develop methods and tools to advance sustainable development in mining, focusing on water and tailings management. The strategies and tools proposed can be applied in mining processes to mitigate environmental impacts and enable the sustainable development of this industry. Methods used in this dissertation include mathematical optimisation, economic valuation methods and sensitivity and uncertainty analyses. To improve water management for mining companies, we proposed a method to supply water to several mine sites with the option of producing energy in the network. Another contribution was a framework to improve the water-energy nexus in mine sites, focusing on tailings disposal technologies. The methods used to accomplish this goal were a water reduction model, real options approach, and sensitivity and uncertainty analyses. Results show that an integrated system to supply water for mining companies, including energy production in the network, can be cheaper than an independent supply for each company. Moreover, dewatering technologies for tailings will reduce the water requirement to the mine site, reducing overall costs and reducing energy consumption in water transport and treatment. To improve mine tailings management, besides the use of dewatering technologies to recover water, the reprocessing of tailings is proposed to recover critical raw materials (CRMs) since some tailings contain quantities of them. A framework is applied, that includes quantifying CRMs in tailings, economic assessment using the discounted cash flow (DCF) method, and a real options approach with sensitivity and uncertainty analyses. Results show that tailings have quantities of CRMs. Tailings can be a secondary source of these materials in the future, under the right conditions of capital expenditure, operating expenditure and prices. This dissertation provides a collection of methods to improve tailings and water management in mining. This study’s novelty consists of considering both water and tailings to enhance the management of tailings and water supply to mine companies by considering the energy component of water treatment, transport and water used in tailings disposal. In addition, the possibility of obtaining CRMs from tailings is studied using an economic approach that introduces real options analysis to complement traditional valuation tools. The importance of this dissertation relies on proposing methods and tools to guide mining towards more sustainable water and tailings management that includes recovery of water and CRMs from tailings.

  • Open Access English
    Authors: 
    Ramírez Angel, Yendery;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Water and energy use are intrinsically intertwined and are critical factors influencing mining sustainability. The rising demand for metals and the decrease of ore grade cause the increase of water volume required and the waste amount generated. Moreover, the reprocessing of mine tailings for the recovery of valuable materials trigger consumption of water and energy. All those factors are a threat to sustainability. The water-energy nexus in the mining industry has a significant impact on sustainability since decreasing waste by reusing, recycling, and reducing the water and energy consumption. Therefore, urge the need for suitable management of water and energy use that lead the way for sustainable mining industry in the context of the circular economy to attain the rising problems. The dissertation aims to provide an insight into the decision-making process to ensure the sustainable operation of mining processes and the related reprocessing of production waste. It is obtained through a comprehensive assessment of technological, environmental, and economic aspects of the operations concerned. The water-energy nexus analysis is applied through the development of frameworks to facilitate and support the decision-making process of stakeholders, to improve the water and waste management in the mining industry that leads to a sustainable circular economy. The main outputs of the dissertation are: The technology assessment provides an insight to decision-makers to aid them to improve technologies so that they can meet specific customers’ demands; The environmental assessment offers a straightforward and fast analysis of the energy consumption influence in water treatment and distribution systems and its effect onto the environment, considering water distribution systems, water quality, and how energy affects these variables; The economic assessment of the feasibility of reprocessing mining tailings to recover critical raw materials, considering the uncertainties involved; and the water-energy nexus assessment on tailings facilities to found and optimised the trade-offs between water and energy. Therefore, obtaining the guidance for proper mine tailings and water management in the mining industry.

  • Open Access English
    Authors: 
    Ram, Manish;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    There are undeniable signs from all over the world demonstrating that climate change is already upon us. Numerous scientific studies have warned of dire consequences should humankind fail to keep average global temperatures from rising beyond 1.5°C. Drastic measures to eliminate greenhouse gas emissions from all economic activities across the world are essential. Major emphasis has been on the energy sector, which contributes the bulk of GHG emissions. Inevitably, energy scenarios describing future transition pathways towards low, and zero emissions energy systems are commonly proposed as mitigation strategies. However, there is growing awareness in the research community that energy transitions should be understood and analysed not only from technical and economical perspectives but also from a social perspective. This research explores the broader ramifications of a global energy transition from various dimensions: costs and externalities of energy production, democratisation of future energy systems and the role of prosumers, employment creation during energy transitions at the global, regional and national levels and the effects of air pollution during energy transitions across the world. This research builds on fundamental techno-economic principles of energy systems and relies firmly on a cost driven rationale for determining cost optimal energy system transition pathways. Techno-economic analyses of energy transitions around the world are executed with the LUT Energy System Transition Model, while the corresponding socioeconomic aspects are expressed in terms of levelised cost of electricity, cost effective development of prosumers, job creation, and the reduction of greenhouse gas emissions along with air pollution. Findings during the course of this original research involved novel assessments of the levelised cost of electricity encompassing externalities across G20 countries, cost optimal prosumer modelling across the world, estimates of job creation potential of various renewables, storage and power-to-X technologies including the production of green hydrogen and e-fuels during global, regional and national energy transitions. The novel research methods and insights are published in several articles and presented in this thesis, which highlight robust socioeconomic benefits of transitioning the current fossil fuels dominated global energy system towards renewables complemented by storage and flexible power-to-X solutions, resulting in near zero emissions of greenhouse gases and air pollutants. These research findings and insights have significant relevance to stakeholders across the energy landscape and present a compelling case for the rapid transformation of energy systems across the world. However, the research does have limitations and is based on energy transition pathways that are inherent with uncertainties and some socioeconomic challenges. Nonetheless, actions to enhance and accelerate the ongoing energy transition across the world must be prioritised, if not for technical feasibility or economic viability, but for the social wellbeing of human society and future generations.

  • Open Access English
    Authors: 
    Qorri, Ardian;
    Publisher: Lappeenranta-Lahti University of Technology LUT
    Country: Finland

    Supply chains are the backbone behind companies. Integrating sustainability in supply chains is difficult but essential to gain competitive advantages. While sustainability recognizes the interdependence of environmental, social, and economic aspects, measuring and managing performance across chain partners is challenging. The information generated from measurement process is used by management to control, communicate, and improve their efforts and relationships with partners. Hence, supply chain sustainability measurement and management are critical in achieving firm’s strategic objectives. However, existing performance measurement and management tools fail to consider all sustainability aspects across supply chain practices and partners. The goal of this dissertation is to explore and develop approaches for measuring and managing sustainability performance of supply chains. By applying a mixed methodology including a systematic literature review, conceptual design, content analysis, metaanalysis, fuzzy Entropy, fuzzy TOPSIS, and sensitivity analysis, I develop a novel and practical method to measure and manage sustainability performance in supply chains. The results of this dissertation have been published in four articles, for which the data was gathered through several sources. The results show (i) the state of the art of sustainability performance measurement approaches; (ii) the proposed conceptual framework explains new relationships between sustainability performance measurement components and stakeholders; (iii) the effect of social and environmental supply practices on firm performance; and (iv) sensitivity analysis confirm that the proposed measurement approach is practical and generates robust and usable outcomes. The dissertation contributes to the literature by providing new insights for scholars, managers, policymakers, and other stakeholders regarding environmental and social supply practices for achieving sustainable development.

  • Open Access English
    Authors: 
    Koskinen, Pilvi;
    Country: Finland

    In recent years, the growth of environmental and climate awareness has been strongly reflected in global politics. The pressure to bring food packaging into line with sustainability is a topical matter influencing society. This master's thesis examines the media debate on the sustainability of food packaging in the Finnish news media. From a sample of three Finnish newspapers classified as high-quality from January 2010 to December 2020, the author of this master's thesis identified news articles on food packaging sustainability based on certain criteria. The analyses looked at the variety of different themes that were addressed in the debate on the sustainability of food packaging in newspapers, and what innovations were proposed for the sustainability transition of food packaging. There were 216 ‘food packaging’ news articles in these newspapers during this period. These news articles were divided into eleven main themes based on their essential content. The themes identified were business solutions and innovations, plastic separating, collecting, recycling, reusing, and reducing, recycling enthusiasm and problems at the consumer, municipal, and state levels, laws and regulations, marine litter and micro-plastics, food safety, issues with plastic substitutes, energy waste, over-packaging, plastics industry, and food waste. Some of the themes appeared in the data more and some less. Of the news articles, 31% mentioned innovations. The majority of the innovations were considering new innovative materials for replacing fossil-based plastics from food packaging. The three main materials mentioned were bioplastic, cardboard, and wood. Both cardboard and bioplastic were mainly wood-based in the research material. The number of food packaging news articles and proposed innovations both peaked in 2018. The coverage of food packaging and the different themes in Finnish newspapers from the perspective of sustainability and sustainability transitions increased considerably during the research period. Based on mitigating the effects of climate change while maintaining food security, the choice of food packaging materials will play an increasingly important role in the future. Viime vuosien ympäristö- ja ilmastotietoisuuden kasvu on heijastunut voimakkaasti globaaliin politiikkaan. Elintarvikepakkausalan kestävyysmuutokset ovat ajankohtainen ja yhteiskunnassa laajalti vaikuttava asia. Tässä pro gradu -työssä tarkastellaan elintarvikepakkausten kestävyydestä käytävää mediakeskustelua suomalaisessa uutismediassa. Pro gradu -työn tekijä tunnisti elintarvikepakkauksia koskevia artikkeleita tiettyjen kriteerien perusteella kolmen laadukkaaksi luokitellun suomalaisen sanomalehden otoksesta. Tutkimusjakso oli tammikuusta 2010 joulukuuhun 2020. Analyysissa tarkasteltiin elintarvikepakkausten kestävyyden teemoja sekä sitä, millaisia innovaatioita elintarvikepakkausten kestävyyssiirtymään mainittiin näissä sanomalehdissä. Sanomalehdistä löytyi tarkasteluajanjakson ajalta 216 uutisartikkelia, jotka käsittelivät elintarvikepakkauksia kestävän kehityksen ja kestävyysmuutosten näkökulmasta. Nämä uutisartikkelit jaettiin yhteentoista pääteemaan olennaisen sisällön perusteella. Löydettyjä teemoja olivat liiketoiminnalliset ratkaisut ja innovaatiot, muovien erottelu, keräys, kierrätys, uusiokäyttö ja käytön vähentäminen, innostus ja ongelmat liittyen kierrätykseen, lait ja määräykset, meriroska ja mikromuovit, elintarviketurvallisuus, muovinkorvikkeiden ongelmat, energiajae ja jätteiden poltto, ylipakkaaminen, yrittäjyys muovialalla, ja ruokahävikki. Osa teemoista toisia sai laajempaa mediahuomiota. Uutisartikkeleista 31 %:ssa mainittiin innovaatiot. Suurin osa innovaatioista koski uusia materiaaleja fossiilipohjaisen muovin korvaamiseksi elintarvikepakkauksista. Kolme korvaamiseen ehdotettua päämateriaalia olivat biomuovi, kartonki ja puupohjaiset materiaalit. Sekä kartonki että biomuovi olivat tässä aineistossa pääasiassa puupohjaisia. Sekä uutisartikkelien, että ehdotettujen innovaatioiden määrä saavutti huippunsa vuonna 2018. Elintarvikepakkausten uutiskattavuus suomalaisissa sanomalehdissä kestävyysajattelun ja kestävyysmuutosten näkökulmasta kasvoi merkittävästi tutkimusjakson aikana. Asiaa koskevat teemat lisääntyivät ja laajenivat tutkimusvuosien aikana. Ilmastonmuutoksen vaikutusten lieventämiseen ja elintarviketurvan säilyttämiseen perustuen elintarvikkeiden pakkausmateriaalien valinnalla on tulevaisuudessa yhä tärkeämpi rooli.

  • Open Access English
    Authors: 
    Laine, Aki;
    Country: Finland

    This bachelor’s thesis examines the sustainability effects of utilizing cloud and edge computing in the manufacturing industry. Additionally, the concept of edge cloud computing and its benefits are presented. The topic is examined by analyzing the sustainability of cloud and edge computing solutions and their use cases in manufacturing. The research is conducted as a literature review and industry published material is also used to understand market needs for these technologies. The results indicate that utilizing cloud and edge computing in manufacturing for purposes such as data analysis, automation, and interorganizational collaboration can offer significant sustainability improvements. These include better resource and energy efficiency, improved productivity, safety, quality, flexibility, and scalability. Cost savings and reductions in waste and downtime can also be achieved. Research shows that cloud computing is more sustainable and energy efficient than its alternative, localized servers. Edge computing solutions offer lower latency compared to centralized data centers. Furthermore, edge computing enables savings in energy consumption and costs by reducing the amount of required data transportation. Decentralizing cloud resources into edge cloud data centers offers computing capabilities with low latency. This allows hosting latency critical applications that exceed the computing capacity of edge devices. Furthermore, edge cloud data centers can enable significant energy and cost savings for applications that are not compute-intensive. Latency tolerant compute-intensive applications should be hosted in larger centralized data centers with higher energy efficiency and processing capacity. Tässä kandidaatintyössä tutkitaan pilvi- ja reunalaskennan hyödyntämisen kestävyysvaikutuksia valmistavassa teollisuudessa. Lisäksi esitellään, mitä reunapilvilaskenta tarkoittaa ja millaisia hyötyjä sillä voidaan saavuttaa. Työssä tarkastellaan pilvi- ja reunalaskentaratkaisujen kestävyystekijöitä sekä valmistavan teollisuuden käyttötapauksia. Tutkimus on toteutettu kirjallisuuskatsauksena. Myös yritysten julkaisemaa materiaalia on hyödynnetty teknologioiden markkinatarpeiden ymmärtämiseksi. Tulokset osoittavat, että valmistavassa teollisuudessa voidaan saavuttaa merkittäviä kestävyyshyötyjä käyttämällä pilvi- ja reunalaskentaa data-analyysissa, automaatiossa ja organisaatioiden välisen yhteistyön edistämisessä. Näitä hyötyjä ovat parempi resurssi- ja energiatehokkuus, korkeampi tuottavuus, turvallisuus, laatu, joustavuus ja skaalautuvuus. Teknologioiden hyödyntäminen mahdollistaa myös hävikin ja häiriöiden vähentämisen sekä tuo kustannussäästöjä. Pilvilaskennan voidaan todeta olevan ympäristöystävällisempi ja kustannustehokkaampi vaihtoehto kuin paikallisten palvelimien käyttäminen. Reunalaskentaratkaisut tarjoavat lyhyemmän viiveen kuin keskitetyt datakeskukset. Lisäksi reunalaskenta vähentää datansiirron tarvetta, mikä mahdollistaa energiasäästöjä. Pilviresurssien hajauttaminen reunapilvidatakeskuksiin tarjoaa laskentakapasiteettia lyhyellä viiveellä. Tämä mahdollistaa reunalaitteiden laskentakapasiteetin ylittävien viivekriittisten sovellusten tarjoamisen. Reunapilvidatakeskuksilla voidaan myös saavuttaa huomattavia kustannus- ja energiasäästöjä sovelluksissa, jotka eivät vaadi suurta prosessointitehoa. Sovellukset, jotka vaativat suuren prosessointitehon ja kestävät viivettä, kannattaa pitää suuremmissa keskitetyissä datakeskuksissa.

  • Open Access Finnish
    Authors: 
    Lindholm, Kimmo;
    Country: Finland

    Sähkönjakeluverkon haltijan pitää varautua normaaliolojen häiriötilanteisiin sekä valmiuslaissa tarkoitettuihin poikkeusoloihin. Normaaliolojen häiriötilanteissa ja poikkeusoloissa, kun yleinen sähkönjakelu on keskeytynyt, tarvitaan varatuotantojärjestelmiä, jotta keskeytyskriittistä toimintaa voidaan jatkaa yleisestä sähköverkosta erotetussa saarekkeessa. Normaalioloissa osaa sähköenergian varatuotantolaitteistoista voidaan käyttää uusiutuvan sähköenergian lähteinä. Sähkönjakeluverkon haltijan on huolehdittava jakeluverkon sähköturvallisuudesta ja suojausten toimivuudesta kaikissa käyttötilanteissa ja olosuhteissa. Tässä opinnäytetyössä tarkastellaan varatuotantojärjestelmiä, jotka liitetään valmiiseen olemassa olevaan sähkönjakeluverkkoon. Tällöin erityisesti saarekekäyttö asettaa tuotantolaitteistolle tiettyjä vaatimuksia, jotta sähköturvallisuus ja suojaukset pysyvät vaaditulla tasolla. Tässä opinnäytetyössä tarkastellaan sähköenergian tuotantolaitteistojen ominaisuuksia, jotka pitää ottaa huomioon suunnittelussa ja tuotantolaitteistojen valinnassa. Tarkasteltavat tuotantolaitteistot ovat diesel-varavoimakone, aurinkosähkövoimala ja akkuenergiavarasto. Opinnäytetyössä havaitaan, että ylivirta- ja vikasuojauksen toimivuuden kannalta olennaisin ominaisuus on tuotantolaitteiston virransyöttökyky erityisesti oikosulussa. Virransyöttökykyä vaaditaan vikatilanteessa oikosulussa olevan sähkönjakeluverkon osan suojalaitteen toimimiseksi. Tuotantolaitteiston on pystyttävä tuottamaan riittävä oikosulkuvirta myös sähkönjakelujärjestelmän kauimmaisiin ja epäedullisimpiin kohtiin. Tarkasteltujen sähköenergian tuotantolaitteistojen virransyöttökyky poikkeaa olennaisesti toisistaan. Tuotantolaitteiston keskijänniteverkon yli syöttämää vikavirtaa ei voida pienjänniteverkossa sähköasennustesterillä mittaamalla todentaa, kuten yleisen sähköverkon syöttäessä vikavirtaa, vaan siihen tarvitaan verkostolaskentaa. Opinnäytetyössä esitellään laskentamenetelmät ja tarkastellaan ylivirta- ja vikasuojauksen toteutuminen erään kohteen osalta. The operator of the electricity distribution system must be prepared for disruptions to normal conditions as well as exceptional conditions referred to in the emergency act. In the event of disruptions to normal conditions and exceptional conditions, when the general electricity distribution has been interrupted, backup production systems are needed so that interruption-critical operations can be continued in an island separated from the general electricity grid. Under normal conditions, part of the backup electricity production system can be used as sources of renewable electrical energy, in which case the production corresponds to small-scale production according to the definition of the electricity market act, if it falls below the specified power limit. The owner of the electricity distribution network must take care of the electrical safety of the distribution network and the functionality of the protections in all operating situations and conditions. This thesis examines back-up production systems that are connected to a ready-made existing electricity distribution network. In this case, island operation in particular places certain requirements on production systems, so that electrical safety and protections remain at the required level. The thesis examines the characteristics of electrical energy production systems, which must be taken into account in the design and selection of production systems. The production systems under consideration are a diesel back-up generator, a solar power plant and a battery energy storage. In the thesis, it is found that the most essential feature in terms of the functionality of overcurrent and fault protection is the current supply capability of the production system, especially in the event of a short circuit. The production system must be able to produce sufficient short-circuit current even to the farthest and most unfavorable parts of the electricity distribution system. The current supply capacity of the examined electrical energy production systems differs substantially from one another.

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